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Rename CONFIG_ATH79 to CONFIG_ARCH_ATH79 #1

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AlbanBedel opened this issue Nov 17, 2015 · 1 comment
Closed

Rename CONFIG_ATH79 to CONFIG_ARCH_ATH79 #1

AlbanBedel opened this issue Nov 17, 2015 · 1 comment

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@AlbanBedel
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The symbol name is inconsistent with other architectures.

AlbanBedel pushed a commit that referenced this issue Nov 18, 2015
When new maps are cloned out of split map they are added into origin
map's group, but their groups pointer is not updated.

This could lead to a segfault, because map->groups is expected to be
always set as reported by Markus:

  __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
  238             return __machine__kernel_map(map->groups->machine, map->type) =
  (gdb) bt
  #0  __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
  #1  0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry
  #2  0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry
  #3  0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi
  #4  0x00000000004b941f in map__load (filter=0x4393c0 <symbol_filter>, map=<opti
  #5  map__find_symbol (map=0x1abb7a0, addr=40188, filter=0x4393c0 <symbol_filter
  ...

Adding __map_groups__insert function to add map into groups together
with map->groups pointer update. It takes no lock as opposed to existing
map_groups__insert, as maps__fixup_overlappings(), where it is being
called, already has the necessary lock held.

Using __map_groups__insert to add new maps after map split.

Reported-by: Markus Trippelsdorf <[email protected]>
Signed-off-by: Jiri Olsa <[email protected]>
Tested-by: Markus Trippelsdorf <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Fixes: cfc5acd ("perf top: Filter symbols based on __map__is_kernel(map)")
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
On systems without AP bus (e.g. KVM) the kernel crashes during init
calls when zcrypt is built-in:

kernel BUG at drivers/base/driver.c:153!
illegal operation: 0001 ilc:1 [#1] SMP
Modules linked in:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.2.0+ torvalds#221
task: 0000000010a40000 ti: 0000000010a48000 task.ti:0000000010a48000
Krnl PSW : 0704c00180000000 0000000000592bd6(driver_register+0x106/0x140)
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
           0000000000000012 0000000000000000 0000000000c45328 0000000000c44e30
           00000000009ef63c 000000000067f598 0000000000cf3c58 0000000000000000
           000000000000007b 0000000000cb1030 0000000000000002 0000000000000000
           0000000000ca8580 0000000010306700 00000000001001d8 0000000010a4bd88
Krnl Code: 0000000000592bc6: f0b00004ebcf	srp 4(12,%r0),3023(%r14),0
           0000000000592bcc: f0a0000407f4       srp     4(11,%r0),2036,0
          #0000000000592bd2: a7f40001           brc     15,592bd4
          >0000000000592bd6: e330d0000004       lg      %r3,0(%r13)
           0000000000592bdc: c0200021edfd       larl    %r2,9d07d6
           0000000000592be2: c0e500126d8f       brasl   %r14,7e0700
           0000000000592be8: e330d0080004       lg      %r3,8(%r13)
           0000000000592bee: a7f4ffab           brc     15,592b44
Call Trace:
([<00000000001001c8>] do_one_initcall+0x90/0x1d0)
 [<0000000000c6dd34>] kernel_init_freeable+0x1e4/0x2a0
 [<00000000007db53a>] kernel_init+0x2a/0x120
 [<00000000007e8ece>] kernel_thread_starter+0x6/0xc
 [<00000000007e8ec8>] kernel_thread_starter+0x0/0xc
Last Breaking-Event-Address:
 [<0000000000592bd2>] driver_register+0x102/0x140

When zcrypt is built as a module, the module loader ensures that the
driver modules cannot be loaded if the AP bus module returns an error
during initialisation. But if zcrypt and the driver are built-in, the
driver is getting initialised even if the AP bus initialisation
failed. The driver invokes ap_driver_register() during initialisation,
which then causes operations on uninitialised data structures to be
performed.

Explicitly protect ap_driver_register() by introducing an
"initialised" flag that gets set iff the AP bus initialisation was
successful. When the AP bus initialisation failed,
ap_driver_register() will error out with -ENODEV, causing the driver
initialisation to fail as well.

Test results:
1. Inside KVM (no AP bus), zcrypt built-in

   Boots. /sys/bus/ap not present (expected).

2. Inside KVM (no AP bus), zcrypt as module

   Boots. Loading zcrypt_cex4 fails because loading ap_bus fails
   (expected).

3. On LPAR with CEX5, zcrypt built-in

   Boots. /sys/bus/ap/devices/card* present but .../card*/type missing
   (i.e. zcrypt_device_register() fails, unrelated issue).

4. On LPAR with CEX5, zcrypt as module

   Boots. Loading zcrypt_cex4 successful,
   /sys/bus/ap/devices/card*/type present. No further testing
   (user-space functionality) was done.

Signed-off-by: Sascha Silbe <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
If CONFIG_PREEMPT=y:

    Unable to handle kernel NULL pointer dereference at virtual address 00000014
    pgd = c0003000
    [00000014] *pgd=80000040004003, *pmd=00000000
    Internal error: Oops: 206 [#1] PREEMPT SMP ARM
    Modules linked in:
    CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G        W       4.3.0-rc3-koelsch-022
    71-g705498fc5e6a5da8-dirty #1789
    Hardware name: Generic R8A7791 (Flattened Device Tree)
    Workqueue: pm pm_runtime_work
    task: ef578e40 ti: ef57a000 task.ti: ef57a000
    PC is at usb_dmac_chan_halt+0xc/0xc0
    LR is at usb_dmac_runtime_suspend+0x28/0x38
    pc : [<c023c880>]    lr : [<c023c95c>]    psr: 80000113
    sp : ef57bdf8  ip : 00000008  fp : 00000003
    r10: 00000008  r9 : c06ab928  r8 : ef49e810
    r7 : 00000000  r6 : 000000ac  r5 : ef770010  r4 : 00000000
    r3 : 00000000  r2 : 8ffc2b84  r1 : 00000000  r0 : ef770010
    Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
    Control: 30c5307d  Table: 40003000  DAC: fffffffd
    Process kworker/0:1 (pid: 17, stack limit = 0xef57a210)
    Stack: (0xef57bdf8 to 0xef57c000)

    [...

    [<c023c880>] (usb_dmac_chan_halt) from [<c023c95c>] (usb_dmac_runtime_suspend+0x28/0x38)
    [<c023c95c>] (usb_dmac_runtime_suspend) from [<c027b25c>] (pm_genpd_runtime_suspend+0x74/0x23c)

This happens because usb_dmac_probe() calls pm_runtime_put() before
usb_dmac_chan_probe(), leading to the device being suspended before the
DMA channels are initialized, causing a NULL pointer dereference.

Move the call to pm_runtime_put() to the end of usb_dmac_probe() to fix
this.

Add a check to usb_dmac_runtime_suspend() to prevent the crash from
happening in the error path.

Reported-by: Sergei Shtylyov <[email protected]>
Signed-off-by: Geert Uytterhoeven <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Signed-off-by: Vinod Koul <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
We try to convert the old way of of specifying fb tiling (obj->tiling)
into the new fb modifiers. We store the result in the passed in mode_cmd
structure. But that structure comes directly from the addfb2 ioctl, and
gets copied back out to userspace, which means we're clobbering the
modifiers that the user provided (all 0 since the DRM_MODE_FB_MODIFIERS
flag wasn't even set by the user). Hence if the user reuses the struct
for another addfb2, the ioctl will be rejected since it's now asking for
some modifiers w/o the flag set.

Fix the problem by making a copy of the user provided structure. We can
play any games we want with the copy.

IGT-Version: 1.12-git (x86_64) (Linux: 4.4.0-rc1-stereo+ x86_64)
...
Subtest basic-X-tiled: SUCCESS (0.001s)
Test assertion failure function pitch_tests, file kms_addfb_basic.c:167:
Failed assertion: drmIoctl(fd, DRM_IOCTL_MODE_ADDFB2, &f) == 0
Last errno: 22, Invalid argument
Stack trace:
  #0 [__igt_fail_assert+0x101]
  #1 [pitch_tests+0x619]
  #2 [__real_main426+0x2f]
  #3 [main+0x23]
  #4 [__libc_start_main+0xf0]
  #5 [_start+0x29]
  torvalds#6 [<unknown>+0x29]
  Subtest framebuffer-vs-set-tiling failed.
  **** DEBUG ****
  Test assertion failure function pitch_tests, file kms_addfb_basic.c:167:
  Failed assertion: drmIoctl(fd, DRM_IOCTL_MODE_ADDFB2, &f) == 0
  Last errno: 22, Invalid argument
  ****  END  ****
  Subtest framebuffer-vs-set-tiling: FAIL (0.003s)
  ...

IGT-Version: 1.12-git (x86_64) (Linux: 4.4.0-rc1-stereo+ x86_64)
Subtest framebuffer-vs-set-tiling: SUCCESS (0.000s)

Cc: [email protected] # v4.1+
Cc: Daniel Vetter <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Fixes: 2a80ead ("drm/i915: Add fb format modifier support")
Testcase: igt/kms_addfb_basic/clobbered-modifier
Signed-off-by: Ville Syrjälä <[email protected]>
Reviewed-by: Daniel Vetter <[email protected]>
Signed-off-by: Jani Nikula <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
For imx27, it needs three clocks to let the controller work,
the old code is wrong, and usbmisc has not included clock handling
code any more. Without this patch, it will cause below data
abort when accessing usbmisc registers.

usbcore: registered new interface driver usb-storage
Unhandled fault: external abort on non-linefetch (0x008) at 0xf4424600
pgd = c0004000
[f4424600] *pgd=10000452(bad)
Internal error: : 8 [#1] PREEMPT ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.1.0-next-20150701-dirty #3089
Hardware name: Freescale i.MX27 (Device Tree Support)
task: c7832b60 ti: c783e000 task.ti: c783e000
PC is at usbmisc_imx27_init+0x4c/0xbc
LR is at usbmisc_imx27_init+0x40/0xbc
pc : [<c03cb5c0>]    lr : [<c03cb5b4>]    psr: 60000093
sp : c783fe08  ip : 00000000  fp : 00000000
r10: c0576434  r9 : 0000009c  r8 : c7a773a0
r7 : 01000000  r6 : 60000013  r5 : c7a776f0  r4 : c7a773f0
r3 : f4424600  r2 : 00000000  r1 : 00000001  r0 : 00000001
Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 0005317f  Table: a0004000  DAC: 00000017
Process swapper (pid: 1, stack limit = 0xc783e190)
Stack: (0xc783fe08 to 0xc7840000)

Signed-off-by: Peter Chen <[email protected]>
Reported-by: Fabio Estevam <[email protected]>
Tested-by: Fabio Estevam <[email protected]>
Cc: <[email protected]> #v4.1+
Acked-by: Shawn Guo <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
The machine hang completely with the following message on the console:

[  487.777538] BUG: unable to handle kernel NULL pointer dereference at 0000000000000060
[  487.777554] IP: [<ffffffff8158aaee>] _raw_spin_lock+0xe/0x30
[  487.777557] PGD 42e9f7067 PUD 42f2fa067 PMD 0
[  487.777560] Oops: 0002 [#1] SMP
...
[  487.777618] CPU: 21 PID: 3190 Comm: Xorg Tainted: G            E   4.4.0-rc1-3-default+ torvalds#6
[  487.777620] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRHSXSD1.86B.0059.R00.1501081238 01/08/2015
[  487.777621] task: ffff880853ae4680 ti: ffff8808696d4000 task.ti: ffff8808696d4000
[  487.777625] RIP: 0010:[<ffffffff8158aaee>]  [<ffffffff8158aaee>] _raw_spin_lock+0xe/0x30
[  487.777627] RSP: 0018:ffff8808696d79c0  EFLAGS: 00010246
[  487.777628] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[  487.777629] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000060
[  487.777630] RBP: ffff8808696d79e0 R08: 0000000000000000 R09: ffff88086924a780
[  487.777631] R10: 000000000001bb40 R11: 0000000000003246 R12: 0000000000000000
[  487.777632] R13: ffff880463a27360 R14: ffff88046ca50218 R15: 0000000000000080
[  487.777634] FS:  00007f3f81c5a8c0(0000) GS:ffff88086f060000(0000) knlGS:0000000000000000
[  487.777635] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  487.777636] CR2: 0000000000000060 CR3: 000000042e678000 CR4: 00000000001406e0
[  487.777638] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  487.777639] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  487.777639] Stack:
[  487.777642]  ffffffffa00eb5fa ffff8808696d7b60 ffff88086b87d800 0000000000000000
[  487.777644]  ffff8808696d7ac8 ffffffffa01694b6 ffff8808696d7ae8 ffffffff8109c8d5
[  487.777647]  ffff880469158740 ffff880463a27000 ffff88086b87d800 ffff88086b87d800
[  487.777647] Call Trace:
[  487.777674]  [<ffffffffa00eb5fa>] ? drm_gem_object_lookup+0x1a/0xa0 [drm]
[  487.777681]  [<ffffffffa01694b6>] mga_crtc_cursor_set+0xc6/0xb60 [mgag200]
[  487.777691]  [<ffffffff8109c8d5>] ? find_busiest_group+0x35/0x4a0
[  487.777696]  [<ffffffff81086294>] ? __might_sleep+0x44/0x80
[  487.777699]  [<ffffffff815888c2>] ? __ww_mutex_lock+0x22/0x9c
[  487.777722]  [<ffffffffa0104f64>] ? drm_modeset_lock+0x34/0xf0 [drm]
[  487.777733]  [<ffffffffa0148d9e>] restore_fbdev_mode+0xee/0x2a0 [drm_kms_helper]
[  487.777742]  [<ffffffffa014afce>] drm_fb_helper_restore_fbdev_mode_unlocked+0x2e/0x70 [drm_kms_helper]
[  487.777748]  [<ffffffffa014b037>] drm_fb_helper_set_par+0x27/0x50 [drm_kms_helper]
[  487.777752]  [<ffffffff8134560c>] fb_set_var+0x18c/0x3f0
[  487.777777]  [<ffffffffa02a9b0a>] ? __ext4_handle_dirty_metadata+0x8a/0x210 [ext4]
[  487.777783]  [<ffffffff8133cb97>] fbcon_blank+0x1b7/0x2b0
[  487.777790]  [<ffffffff813be2a3>] do_unblank_screen+0xb3/0x1c0
[  487.777795]  [<ffffffff813b5aba>] vt_ioctl+0x118a/0x1210
[  487.777801]  [<ffffffff813a8fe0>] tty_ioctl+0x3f0/0xc90
[  487.777808]  [<ffffffff81172018>] ? kzfree+0x28/0x30
[  487.777813]  [<ffffffff811e053f>] ? mntput+0x1f/0x30
[  487.777817]  [<ffffffff811d3f5d>] do_vfs_ioctl+0x30d/0x570
[  487.777822]  [<ffffffff8107ed3a>] ? task_work_run+0x8a/0xa0
[  487.777825]  [<ffffffff811d4234>] SyS_ioctl+0x74/0x80
[  487.777829]  [<ffffffff8158aeae>] entry_SYSCALL_64_fastpath+0x12/0x71
[  487.777851] Code: 65 ff 0d ce 02 a8 7e 5d c3 ba 01 00 00 00 f0 0f b1 17 85 c0 75 e8 b0 01 5d c3 0f 1f 00 65 ff 05 b1 02 a8 7e 31 c0 ba 01 00 00 00 <f0> 0f b1 17 85 c0 75 01 c3 55 89 c6 48 89 e5 e8 4e f5 b1 ff 5d
[  487.777854] RIP  [<ffffffff8158aaee>] _raw_spin_lock+0xe/0x30
[  487.777855]  RSP <ffff8808696d79c0>
[  487.777856] CR2: 0000000000000060
[  487.777860] ---[ end trace 672a2cd555e0ebd3 ]---

The cursor code may be entered with file_priv == NULL && handle == NULL.
The problem was introduced by:

"bf89209 drm/mga200g: Hold a proper reference for cursor_set"

which calls drm_gem_object_lookup(dev, file_priv...). Previously this wasn't
a problem because we checked the handle. Move the check early in the function
can fix the problem.

Signed-off-by: Rui Wang <[email protected]>
Reviewed-by: Daniel Vetter <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
Fix use after free crashes like the following:

 general protection fault: 0000 [#1] SMP
 Call Trace:
  [<ffffffffa0050216>] ? pmem_do_bvec.isra.12+0xa6/0xf0 [nd_pmem]
  [<ffffffffa0050ba2>] pmem_rw_page+0x42/0x80 [nd_pmem]
  [<ffffffff8128fd90>] bdev_read_page+0x50/0x60
  [<ffffffff812972f0>] do_mpage_readpage+0x510/0x770
  [<ffffffff8128fd20>] ? I_BDEV+0x20/0x20
  [<ffffffff811d86dc>] ? lru_cache_add+0x1c/0x50
  [<ffffffff81297657>] mpage_readpages+0x107/0x170
  [<ffffffff8128fd20>] ? I_BDEV+0x20/0x20
  [<ffffffff8128fd20>] ? I_BDEV+0x20/0x20
  [<ffffffff8129058d>] blkdev_readpages+0x1d/0x20
  [<ffffffff811d615f>] __do_page_cache_readahead+0x28f/0x310
  [<ffffffff811d6039>] ? __do_page_cache_readahead+0x169/0x310
  [<ffffffff811c5abd>] ? pagecache_get_page+0x2d/0x1d0
  [<ffffffff811c76f6>] filemap_fault+0x396/0x530
  [<ffffffff811f816e>] __do_fault+0x4e/0xf0
  [<ffffffff811fce7d>] handle_mm_fault+0x11bd/0x1b50

Cc: <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Alexander Viro <[email protected]>
Reported-by: kbuild test robot <[email protected]>
Acked-by: Matthew Wilcox <[email protected]>
[willy: symmetry fixups]
Signed-off-by: Dan Williams <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
It is not permitted to set task state before lock. usblp_wwait sets
the state to TASK_INTERRUPTIBLE and calls mutex_lock_interruptible.
Upon return from that function, the state will be TASK_RUNNING again.

This is clearly a bug and a warning is generated with LOCKDEP too:
WARNING: CPU: 1 PID: 5109 at kernel/sched/core.c:7404 __might_sleep+0x7d/0x90()
do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffffa0c588d0>] usblp_wwait+0xa0/0x310 [usblp]
Modules linked in: ...
CPU: 1 PID: 5109 Comm: captmon Tainted: G        W       4.2.5-0.gef2823b-default #1
Hardware name: LENOVO 23252SG/23252SG, BIOS G2ET33WW (1.13 ) 07/24/2012
 ffffffff81a4edce ffff880236ec7ba8 ffffffff81716651 0000000000000000
 ffff880236ec7bf8 ffff880236ec7be8 ffffffff8106e146 0000000000000282
 ffffffff81a50119 000000000000028b 0000000000000000 ffff8802dab7c508
Call Trace:
...
 [<ffffffff8106e1c6>] warn_slowpath_fmt+0x46/0x50
 [<ffffffff8109a8bd>] __might_sleep+0x7d/0x90
 [<ffffffff8171b20f>] mutex_lock_interruptible_nested+0x2f/0x4b0
 [<ffffffffa0c588fc>] usblp_wwait+0xcc/0x310 [usblp]
 [<ffffffffa0c58bb2>] usblp_write+0x72/0x350 [usblp]
 [<ffffffff8121ed98>] __vfs_write+0x28/0xf0
...

Commit 7f47735 (usblp: Implement the
ENOSPC convention) moved the set prior locking. So move it back after
the lock.

Signed-off-by: Jiri Slaby <[email protected]>
Fixes: 7f47735 ("usblp: Implement the ENOSPC convention")
Acked-By: Pete Zaitcev <[email protected]>
Cc: stable <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
…tart_xfer()

Prior to commit e6c9a03 ("i2c: xiic: Remove the disabling of
interrupts") IRQs where disabled when the initial __xiic_start_xfer() was
called. After the commit the interrupt is enabled while the function is
running, this means it is possible for the interrupt to be triggered while
the function is still running. When this happens the internal data
structures get corrupted and undefined behavior can occur like the
following crash:

	Internal error: Oops: 17 [#1] PREEMPT SMP ARM
	Modules linked in:
	CPU: 0 PID: 2040 Comm: i2cdetect Not tainted 4.0.0-02856-g047a308 #10956
	Hardware name: Xilinx Zynq Platform
	task: ee0c9500 ti: e99a2000 task.ti: e99a2000
	PC is at __xiic_start_xfer+0x6c4/0x7c8
	LR is at __xiic_start_xfer+0x690/0x7c8
	pc : [<c02bbffc>]    lr : [<c02bbfc8>]    psr: 800f0013
	sp : e99a3da8  ip : 00000000  fp : 00000000
	r10: 00000001  r9 : 600f0013  r8 : f0180000
	r7 : f0180000  r6 : c064e444  r5 : 00000017  r4 : ee031010
	r3 : 00000000  r2 : 00000000  r1 : 600f0013  r0 : 0000000f
	Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
	Control: 18c5387d  Table: 29a5404a  DAC: 00000015
	Process i2cdetect (pid: 2040, stack limit = 0xe99a2210)
	Stack: (0xe99a3da8 to 0xe99a4000)
	3da0:                   ee031010 00000000 00000001 ee031020 ee031224 c02bc5ec
	3dc0: ee34c604 00000000 ee0c9500 e99a3dcc e99a3dd0 e99a3dd0 e99a3dd8 c069f0e8
	3de0: 00000000 ee031020 c064e100 ffff90bb e99a3e48 c02b6590 ee031020 00000001
	3e00: e99a3e48 ee031020 00000000 e99a3e63 00000001 c02b6ec4 00000000 00000000
	3e20: 00000000 c02b7320 e99a3ef0 00000000 00000000 e99e3df0 00000000 00000000
	3e40: 00000103 2814575f 0000003e c00a0000 e99a3e85 0001003e ee0c0000 e99a3e63
	3e60: eefd3578 c064e61c ee0c9500 c0041e04 0000056c e9a56db8 00006e5a b6f5c000
	3e80: ee0c9548 eefd0040 00000001 eefd3540 ee0c9500 eefd39a0 c064b540 ee0c9500
	3ea0: 00000000 ee92b000 00000000 bef4862c ee34c600 e99ecdc0 00000720 00000003
	3ec0: e99a2000 00000000 00000000 c02b8b30 00000000 00000000 00000000 e99a3f24
	3ee0: b6e80000 00000000 00000000 c04257e8 00000000 e99a3f24 c02b8f08 00000703
	3f00: 00000003 c02116bc ee935300 00000000 bef4862c ee34c600 e99ecdc0 c02b91f0
	3f20: e99ecdc0 00000720 bef4862c eeb725f8 e99ecdc0 c00c9e2c 00000003 00000003
	3f40: ee248dc0 00000000 ee248dc8 00000002 eeb7c1a8 00000000 00000000 c00bb360
	3f60: 00000000 00000000 00000003 ee248dc0 bef4862c e99ecdc0 e99ecdc0 00000720
	3f80: 00000003 e99a2000 00000000 c00c9f68 00000000 00000000 b6f22000 00000036
	3fa0: c000dfa4 c000de20 00000000 00000000 00000003 00000720 bef4862c bef4862c
	3fc0: 00000000 00000000 b6f22000 00000036 00000000 00000000 b6f60000 00000000
	3fe0: 00013040 bef48614 00008cab b6ecdbe6 400f0030 00000003 2f7fd821 2f7fdc21
	[<c02bbffc>] (__xiic_start_xfer) from [<c02bc5ec>] (xiic_xfer+0x94/0x168)
	[<c02bc5ec>] (xiic_xfer) from [<c02b6590>] (__i2c_transfer+0x4c/0x7c)
	[<c02b6590>] (__i2c_transfer) from [<c02b6ec4>] (i2c_transfer+0x9c/0xc4)
	[<c02b6ec4>] (i2c_transfer) from [<c02b7320>] (i2c_smbus_xfer+0x3a0/0x4ec)
	[<c02b7320>] (i2c_smbus_xfer) from [<c02b8b30>] (i2cdev_ioctl_smbus+0xb0/0x214)
	[<c02b8b30>] (i2cdev_ioctl_smbus) from [<c02b91f0>] (i2cdev_ioctl+0xa0/0x1d4)
	[<c02b91f0>] (i2cdev_ioctl) from [<c00c9e2c>] (do_vfs_ioctl+0x4b0/0x5b8)
	[<c00c9e2c>] (do_vfs_ioctl) from [<c00c9f68>] (SyS_ioctl+0x34/0x5c)
	[<c00c9f68>] (SyS_ioctl) from [<c000de20>] (ret_fast_syscall+0x0/0x34)
	Code: e283300c e5843210 eafffe64 e5943210 (e1d320b4)

The issue can easily be reproduced by performing I2C access under high
system load or IO load.

To fix the issue protect the invocation to __xiic_start_xfer() form
xiic_start_xfer() with the same lock that is used to protect the interrupt
handler.

Fixes: e6c9a03 ("i2c: xiic: Remove the disabling of interrupts")
Signed-off-by: Lars-Peter Clausen <[email protected]>
Reviewed-by: Shubhrajyoti Datta <[email protected]>
Signed-off-by: Wolfram Sang <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 24, 2015
Since commit 7d8c70d ("serial: mctrl-gpio: rename init function"),
crisv32 either do not build or crash as follows.

Unable to handle kernel NULL pointer dereference
Linux 4.3.0-rc7-next-20151101 #1 Sun Nov 1 11:41:28 PST 2015
...
Call Trace: [<c0004a0e>] show_stack+0x0/0x9e
[<c004c0c0>] printk+0x0/0x2c
[<c00059d4>] show_registers+0x14a/0x1c2
[<c004c0c0>] printk+0x0/0x2c
[<c0004b52>] die_if_kernel+0x7c/0x9e
[<c0005346>] do_page_fault+0x32e/0x3e6
[<c01dc59c>] of_get_property+0x0/0x2c
[<c01e0558>] of_irq_parse_raw+0x12a/0x376
[<c01dc59c>] of_get_property+0x0/0x2c
[<c0053aca>] get_page_from_freelist+0x73e/0x856
[<c01dc59c>] of_get_property+0x0/0x2c
[<c0008912>] d_mmu_refill+0x10a/0x112
[<c01b488c>] devm_kmalloc+0x40/0x56
[<c01b47d0>] add_dr+0xc/0x1c
[<c01b4800>] devm_add_action+0x2/0x4e
[<c01abdbc>] mctrl_gpio_init_noauto+0x1c/0x76
[<c01abf9e>] mctrl_gpio_init+0x22/0x110

The function call in the etraxfs-uart driver was not renamed,
possibly due to interference with commit 7b9c516 ("serial:
etraxfs-uart: use mctrl_gpio helpers for handling modem signals").

Fixes: 7d8c70d ("serial: mctrl-gpio: rename init function")
Signed-off-by: Guenter Roeck <[email protected]>
Acked-by: Uwe Kleine-König <[email protected]>
Acked-by: Niklas Cassel <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 25, 2015
…_no_path

In multipath_prepare_ioctl(),
  - pgpath is a path selected from available paths
  - m->queue_io is true if we cannot send a request immediately to
    paths, either because:
      * there is no available path
      * the path group needs activation (pg_init)
          - pg_init is not started
          - pg_init is still running
  - m->queue_if_no_path is true if the device is configured to queue
    I/O if there are no available paths

If !pgpath && !m->queue_if_no_path, the handler should return -EIO.
However in the course of refactoring the condition check has broken
and returns success in that case.  Since bdev points to the dm device
itself, dm_blk_ioctl() calls __blk_dev_driver_ioctl() for itself and
recurses until crash.

You could reproduce the problem like this:

  # dmsetup create mp --table '0 1024 multipath 0 0 0 0'
  # sg_inq /dev/mapper/mp
  <crash>
  [  172.648615] BUG: unable to handle kernel paging request at fffffffc81b10268
  [  172.662843] PGD 19dd067 PUD 0
  [  172.666269] Thread overran stack, or stack corrupted
  [  172.671808] Oops: 0000 [#1] SMP
  ...

Fix the condition check with some clarifications.

Fixes: e56f81e ("dm: refactor ioctl handling")
Signed-off-by: Jun'ichi Nomura <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Mike Snitzer <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>
AlbanBedel pushed a commit that referenced this issue Nov 25, 2015
Liu reported that running certain parts of xfstests threw the
following error:

BUG: sleeping function called from invalid context at mm/page_alloc.c:3190
in_atomic(): 1, irqs_disabled(): 0, pid: 6, name: kworker/u16:0
3 locks held by kworker/u16:0/6:
 #0:  ("writeback"){++++.+}, at: [<ffffffff8107f083>] process_one_work+0x173/0x730
 #1:  ((&(&wb->dwork)->work)){+.+.+.}, at: [<ffffffff8107f083>] process_one_work+0x173/0x730
 #2:  (&type->s_umount_key#44){+++++.}, at: [<ffffffff811e6805>] trylock_super+0x25/0x60
CPU: 5 PID: 6 Comm: kworker/u16:0 Tainted: G           OE   4.3.0+ #3
Hardware name: Red Hat KVM, BIOS Bochs 01/01/2011
Workqueue: writeback wb_workfn (flush-btrfs-108)
 ffffffff81a3abab ffff88042e282ba8 ffffffff8130191b ffffffff81a3abab
 0000000000000c76 ffff88042e282ba8 ffff88042e27c180 ffff88042e282bd8
 ffffffff8108ed95 ffff880400000004 0000000000000000 0000000000000c76
Call Trace:
 [<ffffffff8130191b>] dump_stack+0x4f/0x74
 [<ffffffff8108ed95>] ___might_sleep+0x185/0x240
 [<ffffffff8108eea2>] __might_sleep+0x52/0x90
 [<ffffffff811817e8>] __alloc_pages_nodemask+0x268/0x410
 [<ffffffff8109a43c>] ? sched_clock_local+0x1c/0x90
 [<ffffffff8109a6d1>] ? local_clock+0x21/0x40
 [<ffffffff810b9eb0>] ? __lock_release+0x420/0x510
 [<ffffffff810b534c>] ? __lock_acquired+0x16c/0x3c0
 [<ffffffff811ca265>] alloc_pages_current+0xc5/0x210
 [<ffffffffa0577105>] ? rbio_is_full+0x55/0x70 [btrfs]
 [<ffffffff810b7ed8>] ? mark_held_locks+0x78/0xa0
 [<ffffffff81666d50>] ? _raw_spin_unlock_irqrestore+0x40/0x60
 [<ffffffffa0578c0a>] full_stripe_write+0x5a/0xc0 [btrfs]
 [<ffffffffa0578ca9>] __raid56_parity_write+0x39/0x60 [btrfs]
 [<ffffffffa0578deb>] run_plug+0x11b/0x140 [btrfs]
 [<ffffffffa0578e33>] btrfs_raid_unplug+0x23/0x70 [btrfs]
 [<ffffffff812d36c2>] blk_flush_plug_list+0x82/0x1f0
 [<ffffffff812e0349>] blk_sq_make_request+0x1f9/0x740
 [<ffffffff812ceba2>] ? generic_make_request_checks+0x222/0x7c0
 [<ffffffff812cf264>] ? blk_queue_enter+0x124/0x310
 [<ffffffff812cf1d2>] ? blk_queue_enter+0x92/0x310
 [<ffffffff812d0ae2>] generic_make_request+0x172/0x2c0
 [<ffffffff812d0ad4>] ? generic_make_request+0x164/0x2c0
 [<ffffffff812d0ca0>] submit_bio+0x70/0x140
 [<ffffffffa0577b29>] ? rbio_add_io_page+0x99/0x150 [btrfs]
 [<ffffffffa0578a89>] finish_rmw+0x4d9/0x600 [btrfs]
 [<ffffffffa0578c4c>] full_stripe_write+0x9c/0xc0 [btrfs]
 [<ffffffffa057ab7f>] raid56_parity_write+0xef/0x160 [btrfs]
 [<ffffffffa052bd83>] btrfs_map_bio+0xe3/0x2d0 [btrfs]
 [<ffffffffa04fbd6d>] btrfs_submit_bio_hook+0x8d/0x1d0 [btrfs]
 [<ffffffffa05173c4>] submit_one_bio+0x74/0xb0 [btrfs]
 [<ffffffffa0517f55>] submit_extent_page+0xe5/0x1c0 [btrfs]
 [<ffffffffa0519b18>] __extent_writepage_io+0x408/0x4c0 [btrfs]
 [<ffffffffa05179c0>] ? alloc_dummy_extent_buffer+0x140/0x140 [btrfs]
 [<ffffffffa051dc88>] __extent_writepage+0x218/0x3a0 [btrfs]
 [<ffffffff810b7ed8>] ? mark_held_locks+0x78/0xa0
 [<ffffffffa051e2c9>] extent_write_cache_pages.clone.0+0x2f9/0x400 [btrfs]
 [<ffffffffa051e422>] extent_writepages+0x52/0x70 [btrfs]
 [<ffffffffa05001f0>] ? btrfs_set_inode_index+0x70/0x70 [btrfs]
 [<ffffffffa04fcc17>] btrfs_writepages+0x27/0x30 [btrfs]
 [<ffffffff81184df3>] do_writepages+0x23/0x40
 [<ffffffff81212229>] __writeback_single_inode+0x89/0x4d0
 [<ffffffff81212a60>] ? writeback_sb_inodes+0x260/0x480
 [<ffffffff81212a60>] ? writeback_sb_inodes+0x260/0x480
 [<ffffffff8121295f>] ? writeback_sb_inodes+0x15f/0x480
 [<ffffffff81212ad2>] writeback_sb_inodes+0x2d2/0x480
 [<ffffffff810b1397>] ? down_read_trylock+0x57/0x60
 [<ffffffff811e6805>] ? trylock_super+0x25/0x60
 [<ffffffff810d629f>] ? rcu_read_lock_sched_held+0x4f/0x90
 [<ffffffff81212d0c>] __writeback_inodes_wb+0x8c/0xc0
 [<ffffffff812130b5>] wb_writeback+0x2b5/0x500
 [<ffffffff810b7ed8>] ? mark_held_locks+0x78/0xa0
 [<ffffffff810660a8>] ? __local_bh_enable_ip+0x68/0xc0
 [<ffffffff81213362>] ? wb_do_writeback+0x62/0x310
 [<ffffffff812133c1>] wb_do_writeback+0xc1/0x310
 [<ffffffff8107c3d9>] ? set_worker_desc+0x79/0x90
 [<ffffffff81213842>] wb_workfn+0x92/0x330
 [<ffffffff8107f133>] process_one_work+0x223/0x730
 [<ffffffff8107f083>] ? process_one_work+0x173/0x730
 [<ffffffff8108035f>] ? worker_thread+0x18f/0x430
 [<ffffffff810802ed>] worker_thread+0x11d/0x430
 [<ffffffff810801d0>] ? maybe_create_worker+0xf0/0xf0
 [<ffffffff810801d0>] ? maybe_create_worker+0xf0/0xf0
 [<ffffffff810858df>] kthread+0xef/0x110
 [<ffffffff8108f74e>] ? schedule_tail+0x1e/0xd0
 [<ffffffff810857f0>] ? __init_kthread_worker+0x70/0x70
 [<ffffffff816673bf>] ret_from_fork+0x3f/0x70
 [<ffffffff810857f0>] ? __init_kthread_worker+0x70/0x70

The issue is that we've got the software context pinned while
calling blk_flush_plug_list(), which flushes callbacks that
are allowed to sleep. btrfs and raid has such callbacks.

Flip the checks around a bit, so we can enable preempt a bit
earlier and flush plugs without having preempt disabled.

This only affects blk-mq driven devices, and only those that
register a single queue.

Reported-by: Liu Bo <[email protected]>
Tested-by: Liu Bo <[email protected]>
Cc: [email protected]
Signed-off-by: Jens Axboe <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 4, 2015
Fix issue from two patches overlapping causing a kernel oops

[ 3569.297449] Unable to handle kernel NULL pointer dereference at virtual address 00000088
[ 3569.306272] pgd = dc894000
[ 3569.309287] [00000088] *pgd=00000000
[ 3569.313104] Internal error: Oops: 5 [#1] SMP ARM
[ 3569.317986] Modules linked in: ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_filter ebtable_nat ebtable_broute bridge stp llc ebtables ip6table_security ip6table_raw ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_filter ip6_tables iptable_security iptable_raw iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle musb_dsps cppi41 musb_hdrc phy_am335x udc_core phy_generic phy_am335x_control omap_sham omap_aes omap_rng omap_hwspinlock omap_mailbox hwspinlock_core musb_am335x omap_wdt at24 8250_omap leds_gpio cpufreq_dt smsc davinci_mdio mmc_block ti_cpsw cpsw_common ptp pps_core cpsw_ale davinci_cpdma omap_hsmmc omap_dma mmc_core i2c_dev
[ 3569.386293] CPU: 0 PID: 1429 Comm: wdctl Not tainted 4.3.0-0.rc7.git0.1.fc24.armv7hl #1
[ 3569.394740] Hardware name: Generic AM33XX (Flattened Device Tree)
[ 3569.401179] task: dbd11a00 ti: dbaac000 task.ti: dbaac000
[ 3569.406917] PC is at omap_wdt_get_timeleft+0xc/0x20 [omap_wdt]
[ 3569.413106] LR is at watchdog_ioctl+0x3cc/0x42c
[ 3569.417902] pc : [<bf0ab138>]    lr : [<c0739c54>]    psr: 600f0013
[ 3569.417902] sp : dbaadf18  ip : 00000003  fp : 7f5d3bbe
[ 3569.430014] r10: 00000000  r9 : 00000003  r8 : bef21ab8
[ 3569.435535] r7 : dbbc0f7c  r6 : dbbc0f18  r5 : bef21ab8  r4 : 00000000
[ 3569.442427] r3 : 00000000  r2 : 00000000  r1 : 8004570a  r0 : dbbc0f18
[ 3569.449323] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[ 3569.456858] Control: 10c5387d  Table: 9c894019  DAC: 00000051
[ 3569.462927] Process wdctl (pid: 1429, stack limit = 0xdbaac220)
[ 3569.469179] Stack: (0xdbaadf18 to 0xdbaae000)
[ 3569.473790] df00:                                                       bef21ab8 dbf60e38
[ 3569.482441] df20: dc91b840 8004570a bef21ab8 c03988a4 dbaadf48 dc854000 00000000 dd313850
[ 3569.491092] df40: ddf033b8 0000570a dc91b80b dbaadf3c dbf60e38 00000020 c0df9250 c0df6c48
[ 3569.499741] df60: dc91b840 8004570a 00000000 dc91b840 dc91b840 8004570a bef21ab8 00000003
[ 3569.508389] df80: 00000000 c03989d4 bef21b74 7f5d3bad 00000003 00000036 c020fcc4 dbaac000
[ 3569.517037] dfa0: 00000000 c020fb00 bef21b74 7f5d3bad 00000003 8004570a bef21ab8 00000001
[ 3569.525685] dfc0: bef21b74 7f5d3bad 00000003 00000036 00000001 00000000 7f5e4eb0 7f5d3bbe
[ 3569.534334] dfe0: 7f5e4f10 bef21a3c 7f5d0a54 b6e97e0c a00f0010 00000003 00000000 00000000
[ 3569.543038] [<bf0ab138>] (omap_wdt_get_timeleft [omap_wdt]) from [<c0739c54>] (watchdog_ioctl+0x3cc/0x42c)
[ 3569.553266] [<c0739c54>] (watchdog_ioctl) from [<c03988a4>] (do_vfs_ioctl+0x5bc/0x698)
[ 3569.561648] [<c03988a4>] (do_vfs_ioctl) from [<c03989d4>] (SyS_ioctl+0x54/0x7c)
[ 3569.569400] [<c03989d4>] (SyS_ioctl) from [<c020fb00>] (ret_fast_syscall+0x0/0x3c)
[ 3569.577413] Code: e12fff1e e52de004 e8bd4000 e5903060 (e5933088)
[ 3569.584089] ---[ end trace cec3039bd3ae610a ]---

Cc: <[email protected]> # v4.2+
Signed-off-by: Peter Robinson <[email protected]>
Acked-by: Lars Poeschel <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]>
Signed-off-by: Wim Van Sebroeck <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 4, 2015
If a user key gets negatively instantiated, an error code is cached in the
payload area.  A negatively instantiated key may be then be positively
instantiated by updating it with valid data.  However, the ->update key
type method must be aware that the error code may be there.

The following may be used to trigger the bug in the user key type:

    keyctl request2 user user "" @U
    keyctl add user user "a" @U

which manifests itself as:

	BUG: unable to handle kernel paging request at 00000000ffffff8a
	IP: [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046
	PGD 7cc30067 PUD 0
	Oops: 0002 [#1] SMP
	Modules linked in:
	CPU: 3 PID: 2644 Comm: a.out Not tainted 4.3.0+ torvalds#49
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
	task: ffff88003ddea700 ti: ffff88003dd88000 task.ti: ffff88003dd88000
	RIP: 0010:[<ffffffff810a376f>]  [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280
	 [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046
	RSP: 0018:ffff88003dd8bdb0  EFLAGS: 00010246
	RAX: 00000000ffffff82 RBX: 0000000000000000 RCX: 0000000000000001
	RDX: ffffffff81e3fe40 RSI: 0000000000000000 RDI: 00000000ffffff82
	RBP: ffff88003dd8bde0 R08: ffff88007d2d2da0 R09: 0000000000000000
	R10: 0000000000000000 R11: ffff88003e8073c0 R12: 00000000ffffff82
	R13: ffff88003dd8be68 R14: ffff88007d027600 R15: ffff88003ddea700
	FS:  0000000000b92880(0063) GS:ffff88007fd00000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
	CR2: 00000000ffffff8a CR3: 000000007cc5f000 CR4: 00000000000006e0
	Stack:
	 ffff88003dd8bdf0 ffffffff81160a8a 0000000000000000 00000000ffffff82
	 ffff88003dd8be68 ffff88007d027600 ffff88003dd8bdf0 ffffffff810a39e5
	 ffff88003dd8be20 ffffffff812a31ab ffff88007d027600 ffff88007d027620
	Call Trace:
	 [<ffffffff810a39e5>] kfree_call_rcu+0x15/0x20 kernel/rcu/tree.c:3136
	 [<ffffffff812a31ab>] user_update+0x8b/0xb0 security/keys/user_defined.c:129
	 [<     inline     >] __key_update security/keys/key.c:730
	 [<ffffffff8129e5c1>] key_create_or_update+0x291/0x440 security/keys/key.c:908
	 [<     inline     >] SYSC_add_key security/keys/keyctl.c:125
	 [<ffffffff8129fc21>] SyS_add_key+0x101/0x1e0 security/keys/keyctl.c:60
	 [<ffffffff8185f617>] entry_SYSCALL_64_fastpath+0x12/0x6a arch/x86/entry/entry_64.S:185

Note the error code (-ENOKEY) in EDX.

A similar bug can be tripped by:

    keyctl request2 trusted user "" @U
    keyctl add trusted user "a" @U

This should also affect encrypted keys - but that has to be correctly
parameterised or it will fail with EINVAL before getting to the bit that
will crashes.

Reported-by: Dmitry Vyukov <[email protected]>
Signed-off-by: David Howells <[email protected]>
Acked-by: Mimi Zohar <[email protected]>
Signed-off-by: James Morris <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 4, 2015
OMAP CPU hotplug uses cpu1's clocks and power domains for CPU1 wake up
from low power states (or turn on CPU1). This part of code is also
part of system suspend (disable_nonboot_cpus()).
>From other side, cpu1's clocks and power domains are used by CPUIdle. All above
functionality is mutually exclusive and, therefore, lockless clkdm/pwrdm api
can be used in omap4_boot_secondary().

This fixes below back-trace on -RT which is triggered by
pwrdm_lock/unlock():

BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
 in_atomic(): 1, irqs_disabled(): 0, pid: 118, name: sh
 9 locks held by sh/118:
  #0:  (sb_writers#4){.+.+.+}, at: [<c0144a6c>] vfs_write+0x13c/0x164
  #1:  (&of->mutex){+.+.+.}, at: [<c01b4c70>] kernfs_fop_write+0x48/0x19c
  #2:  (s_active#24){.+.+.+}, at: [<c01b4c78>] kernfs_fop_write+0x50/0x19c
  #3:  (device_hotplug_lock){+.+.+.}, at: [<c03cbff0>] lock_device_hotplug_sysfs+0xc/0x4c
  #4:  (&dev->mutex){......}, at: [<c03cd284>] device_online+0x14/0x88
  #5:  (cpu_add_remove_lock){+.+.+.}, at: [<c003af90>] cpu_up+0x50/0x1a0
  torvalds#6:  (cpu_hotplug.lock){++++++}, at: [<c003ae48>] cpu_hotplug_begin+0x0/0xc4
  torvalds#7:  (cpu_hotplug.lock#2){+.+.+.}, at: [<c003aec0>] cpu_hotplug_begin+0x78/0xc4
  torvalds#8:  (boot_lock){+.+...}, at: [<c002b254>] omap4_boot_secondary+0x1c/0x178
 Preemption disabled at:[<  (null)>]   (null)

 CPU: 0 PID: 118 Comm: sh Not tainted 4.1.12-rt11-01998-gb4a62c3-dirty torvalds#137
 Hardware name: Generic DRA74X (Flattened Device Tree)
 [<c0017574>] (unwind_backtrace) from [<c0013be8>] (show_stack+0x10/0x14)
 [<c0013be8>] (show_stack) from [<c05a8670>] (dump_stack+0x80/0x94)
 [<c05a8670>] (dump_stack) from [<c05ad158>] (rt_spin_lock+0x24/0x54)
 [<c05ad158>] (rt_spin_lock) from [<c0030dac>] (clkdm_wakeup+0x10/0x2c)
 [<c0030dac>] (clkdm_wakeup) from [<c002b2c0>] (omap4_boot_secondary+0x88/0x178)
 [<c002b2c0>] (omap4_boot_secondary) from [<c0015d00>] (__cpu_up+0xc4/0x164)
 [<c0015d00>] (__cpu_up) from [<c003b09c>] (cpu_up+0x15c/0x1a0)
 [<c003b09c>] (cpu_up) from [<c03cd2d4>] (device_online+0x64/0x88)
 [<c03cd2d4>] (device_online) from [<c03cd360>] (online_store+0x68/0x74)
 [<c03cd360>] (online_store) from [<c01b4ce0>] (kernfs_fop_write+0xb8/0x19c)
 [<c01b4ce0>] (kernfs_fop_write) from [<c0144124>] (__vfs_write+0x20/0xd8)
 [<c0144124>] (__vfs_write) from [<c01449c0>] (vfs_write+0x90/0x164)
 [<c01449c0>] (vfs_write) from [<c01451e4>] (SyS_write+0x44/0x9c)
 [<c01451e4>] (SyS_write) from [<c0010240>] (ret_fast_syscall+0x0/0x54)
 CPU1: smp_ops.cpu_die() returned, trying to resuscitate

Cc: Tero Kristo <[email protected]>
Signed-off-by: Grygorii Strashko <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 4, 2015
Originally OMAP MPUIO GPIO irqchip was implemented using Generic irq
chip, but after set of reworks Generic irq chip code was replaced by
common OMAP GPIO implementation and finally removed by
commit d2d05c6 ("gpio: omap: Fix regression for MPUIO interrupts").
Unfortunately, above commit left .irq_mask/unmask callbacks assigned
as below for MPUIO GPIO case:
	irqc->irq_mask = irq_gc_mask_set_bit;
	irqc->irq_unmask = irq_gc_mask_clr_bit;

This now causes boot failure on OMAP1 platforms, after
commit 450fa54 ("gpio: omap: convert to use generic irq handler")
which forces these callbacks to be called during GPIO IRQs mapping
from gpiochip_irq_map:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 75 [#1] ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.4.0-rc1-e3-los_afe0c+-00002-g25379c0-dirty #1
Hardware name: Amstrad E3 (Delta)
task: c1836000 ti: c1838000 task.ti: c1838000
PC is at irq_gc_mask_set_bit+0x1c/0x60
LR is at __irq_do_set_handler+0x118/0x15c
pc : [<c004848c>]    lr : [<c0047d4c>]    psr: 600000d3
sp : c1839c90  ip : c1862c64  fp : c1839c9c
r10: 00000000  r9 : c041195  r8 : c0411bbc
r7 : 00000000  r6 : c185c310  r5 : c00444e8  r4 : c185c300
r3 : c1854b50  r2 : 00000000  r1 : 00000000  r0 : c185c310
Flags: nZCv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment kernel
Control: 0000317f  Table: 10004000  DAC: 00000057
Process swapper (pid: 1, stack limit = 0xc1838190)
Stack: (0xc1839c90 to 0xc183a000)

[...]

Backtrace:
[<c0048470>] (irq_gc_mask_set_bit) from [<c0047d4c>] (__irq_do_set_handler+0x118/0x15c)
[<c0047c34>] (__irq_do_set_handler) from [<c0047dd4>] (__irq_set_handler+0x44/0x5c)
 r6:00000000 r5:c00444e8 r4:c185c300
[<c0047d90>] (__irq_set_handler) from [<c0047e1c>] (irq_set_chip_and_handler_name+0x30/0x34)
 r7:00000050 r6:00000000 r5:c00444e8 r4:00000050
[<c0047dec>] (irq_set_chip_and_handler_name) from [<c01b345c>] (gpiochip_irq_map+0x3c/0x8c)
 r7:00000050 r6:00000000 r5:00000050 r4:c1862c64
[<c01b3420>] (gpiochip_irq_map) from [<c0049670>] (irq_domain_associate+0x7c/0x1c4)
 r5:c185c310 r4:c185cb00
[<c00495f4>] (irq_domain_associate) from [<c0049894>] (irq_domain_add_simple+0x98/0xc0)
 r8:c0411bbc r7:c185cb00 r6:00000050 r5:00000010 r4:00000001
[<c00497fc>] (irq_domain_add_simple) from [<c01b3328>] (_gpiochip_irqchip_add+0x64/0x10c)
 r7:c1862c64 r6:c0419280 r5:c1862c64 r4:c1854b50
[<c01b32c4>] (_gpiochip_irqchip_add) from [<c01b79f4>] (omap_gpio_probe+0x2fc/0x63c)
 r5:c1854b50 r4:c1862c10
[<c01b76f8>] (omap_gpio_probe) from [<c01fcf58>] (platform_drv_probe+0x2c/0x64)
 r10:00000000 r9:c03e45e8 r8:00000000 r7:c0419294 r6:c0411984 r5:c0419294
 r4:c0411950
[<c01fcf2c>] (platform_drv_probe) from [<c01fb668>] (really_probe+0x160/0x29c)

Hence, fix it by remove obsolete callbacks assignment. After this
change 	omap_gpio_mask_irq()/omap_gpio_unmask_irq() will be used
for MPUIO IRQs masking, but this now happens anyway from
omap_gpio_irq_startup/shutdown().

Cc: Tony Lindgren <[email protected]>
Fixes: commit d2d05c6 ("gpio: omap: Fix regression for MPUIO interrupts")
Reported-by: Aaro Koskinen <[email protected]>
Signed-off-by: Grygorii Strashko <[email protected]>
Acked-by: Santosh Shilimkar <[email protected]>
Tested-by: Aaro Koskinen <[email protected]>
Signed-off-by: Linus Walleij <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
When a passive TCP is created, we eventually call tcp_md5_do_add()
with sk pointing to the child. It is not owner by the user yet (we
will add this socket into listener accept queue a bit later anyway)

But we do own the spinlock, so amend the lockdep annotation to avoid
following splat :

[ 8451.090932] net/ipv4/tcp_ipv4.c:923 suspicious rcu_dereference_protected() usage!
[ 8451.090932]
[ 8451.090932] other info that might help us debug this:
[ 8451.090932]
[ 8451.090934]
[ 8451.090934] rcu_scheduler_active = 1, debug_locks = 1
[ 8451.090936] 3 locks held by socket_sockopt_/214795:
[ 8451.090936]  #0:  (rcu_read_lock){.+.+..}, at: [<ffffffff855c6ac1>] __netif_receive_skb_core+0x151/0xe90
[ 8451.090947]  #1:  (rcu_read_lock){.+.+..}, at: [<ffffffff85618143>] ip_local_deliver_finish+0x43/0x2b0
[ 8451.090952]  #2:  (slock-AF_INET){+.-...}, at: [<ffffffff855acda5>] sk_clone_lock+0x1c5/0x500
[ 8451.090958]
[ 8451.090958] stack backtrace:
[ 8451.090960] CPU: 7 PID: 214795 Comm: socket_sockopt_

[ 8451.091215] Call Trace:
[ 8451.091216]  <IRQ>  [<ffffffff856fb29c>] dump_stack+0x55/0x76
[ 8451.091229]  [<ffffffff85123b5b>] lockdep_rcu_suspicious+0xeb/0x110
[ 8451.091235]  [<ffffffff8564544f>] tcp_md5_do_add+0x1bf/0x1e0
[ 8451.091239]  [<ffffffff85645751>] tcp_v4_syn_recv_sock+0x1f1/0x4c0
[ 8451.091242]  [<ffffffff85642b27>] ? tcp_v4_md5_hash_skb+0x167/0x190
[ 8451.091246]  [<ffffffff85647c78>] tcp_check_req+0x3c8/0x500
[ 8451.091249]  [<ffffffff856451ae>] ? tcp_v4_inbound_md5_hash+0x11e/0x190
[ 8451.091253]  [<ffffffff85647170>] tcp_v4_rcv+0x3c0/0x9f0
[ 8451.091256]  [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0
[ 8451.091260]  [<ffffffff856181b6>] ip_local_deliver_finish+0xb6/0x2b0
[ 8451.091263]  [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0
[ 8451.091267]  [<ffffffff85618d38>] ip_local_deliver+0x48/0x80
[ 8451.091270]  [<ffffffff85618510>] ip_rcv_finish+0x160/0x700
[ 8451.091273]  [<ffffffff8561900e>] ip_rcv+0x29e/0x3d0
[ 8451.091277]  [<ffffffff855c74b7>] __netif_receive_skb_core+0xb47/0xe90

Fixes: a8afca0 ("tcp: md5: protects md5sig_info with RCU")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: Willem de Bruijn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
On some host errors storvsc module tries to remove sdev by scheduling a job
which does the following:

   sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
   if (sdev) {
       scsi_remove_device(sdev);
       scsi_device_put(sdev);
   }

While this code seems correct the following crash is observed:

 general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
 RIP: 0010:[<ffffffff81169979>]  [<ffffffff81169979>] bdi_destroy+0x39/0x220
 ...
 [<ffffffff814aecdc>] ? _raw_spin_unlock_irq+0x2c/0x40
 [<ffffffff8127b7db>] blk_cleanup_queue+0x17b/0x270
 [<ffffffffa00b54c4>] __scsi_remove_device+0x54/0xd0 [scsi_mod]
 [<ffffffffa00b556b>] scsi_remove_device+0x2b/0x40 [scsi_mod]
 [<ffffffffa00ec47d>] storvsc_remove_lun+0x3d/0x60 [hv_storvsc]
 [<ffffffff81080791>] process_one_work+0x1b1/0x530
 ...

The problem comes with the fact that many such jobs (for the same device)
are being scheduled simultaneously. While scsi_remove_device() uses
shost->scan_mutex and scsi_device_lookup() will fail for a device in
SDEV_DEL state there is no protection against someone who did
scsi_device_lookup() before we actually entered __scsi_remove_device(). So
the whole scenario looks like that: two callers do simultaneous (or
preemption happens) calls to scsi_device_lookup() ant these calls succeed
for both of them, after that they try doing scsi_remove_device().
shost->scan_mutex only serializes their calls to __scsi_remove_device()
and we end up doing the cleanup path twice.

Signed-off-by: Vitaly Kuznetsov <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
This patch make sure that all necessary members of dwc2_hsotg
are initialized before the irq handler is requested. So
the kernel oops triggered by dwc2_handle_common_intr has
been fixed.

  dwc2 20980000.usb: Configuration mismatch. Forcing host mode
  dwc2 20980000.usb: no platform data or transceiver defined
  Unable to handle kernel paging request at virtual address cc860040
  pgd = c0004000
  [cc860040] *pgd=0b41e811, *pte=00000000, *ppte=00000000
  Internal error: Oops: 7 [#1] ARM
  CPU: 0 PID: 1 Comm: swapper Not tainted 4.3.0-rc3+ torvalds#19
  Hardware name: BCM2835
  task: cb494000 ti: cb4d0000 task.ti: cb4d0000
  PC is at dwc2_is_controller_alive+0x18/0x34
  LR is at dwc2_handle_common_intr+0x24/0xb60

Acked-by: John Youn <[email protected]>
Tested-by: Marek Szyprowski <[email protected]>
Signed-off-by: Stefan Wahren <[email protected]>
Signed-off-by: Felipe Balbi <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
When vrf's ->newlink is called, if register_netdevice() fails then it
does free_netdev(), but that's also done by rtnl_newlink() so a second
free happens and memory gets corrupted, to reproduce execute the
following line a couple of times (1 - 5 usually is enough):
$ for i in `seq 1 5`; do ip link add vrf: type vrf table 1; done;
This works because we fail in register_netdevice() because of the wrong
name "vrf:".

And here's a trace of one crash:
[   28.792157] ------------[ cut here ]------------
[   28.792407] kernel BUG at fs/namei.c:246!
[   28.792608] invalid opcode: 0000 [#1] SMP
[   28.793240] Modules linked in: vrf nfsd auth_rpcgss oid_registry
nfs_acl nfs lockd grace sunrpc crct10dif_pclmul crc32_pclmul
crc32c_intel qxl drm_kms_helper ttm drm aesni_intel aes_x86_64 psmouse
glue_helper lrw evdev gf128mul i2c_piix4 ablk_helper cryptd ppdev
parport_pc parport serio_raw pcspkr virtio_balloon virtio_console
i2c_core acpi_cpufreq button 9pnet_virtio 9p 9pnet fscache ipv6 autofs4
ext4 crc16 mbcache jbd2 virtio_blk virtio_net sg sr_mod cdrom
ata_generic ehci_pci uhci_hcd ehci_hcd e1000 usbcore usb_common ata_piix
libata virtio_pci virtio_ring virtio scsi_mod floppy
[   28.796016] CPU: 0 PID: 1148 Comm: ld-linux-x86-64 Not tainted
4.4.0-rc1+ torvalds#24
[   28.796016] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.8.1-20150318_183358- 04/01/2014
[   28.796016] task: ffff8800352561c0 ti: ffff88003592c000 task.ti:
ffff88003592c000
[   28.796016] RIP: 0010:[<ffffffff812187b3>]  [<ffffffff812187b3>]
putname+0x43/0x60
[   28.796016] RSP: 0018:ffff88003592fe88  EFLAGS: 00010246
[   28.796016] RAX: 0000000000000000 RBX: ffff8800352561c0 RCX:
0000000000000001
[   28.796016] RDX: 0000000000000000 RSI: 0000000000000000 RDI:
ffff88003784f000
[   28.796016] RBP: ffff88003592ff08 R08: 0000000000000001 R09:
0000000000000000
[   28.796016] R10: 0000000000000000 R11: 0000000000000001 R12:
0000000000000000
[   28.796016] R13: 000000000000047c R14: ffff88003784f000 R15:
ffff8800358c4a00
[   28.796016] FS:  0000000000000000(0000) GS:ffff88003fc00000(0000)
knlGS:0000000000000000
[   28.796016] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   28.796016] CR2: 00007ffd583bc2d9 CR3: 0000000035a99000 CR4:
00000000000406f0
[   28.796016] Stack:
[   28.796016]  ffffffff8121045d ffffffff812102d3 ffff8800352561c0
ffff880035a91660
[   28.796016]  ffff8800008a9880 0000000000000000 ffffffff81a49940
00ffffff81218684
[   28.796016]  ffff8800352561c0 000000000000047c 0000000000000000
ffff880035b36d80
[   28.796016] Call Trace:
[   28.796016]  [<ffffffff8121045d>] ?
do_execveat_common.isra.34+0x74d/0x930
[   28.796016]  [<ffffffff812102d3>] ?
do_execveat_common.isra.34+0x5c3/0x930
[   28.796016]  [<ffffffff8121066c>] do_execve+0x2c/0x30
[   28.796016]  [<ffffffff810939a0>]
call_usermodehelper_exec_async+0xf0/0x140
[   28.796016]  [<ffffffff810938b0>] ? umh_complete+0x40/0x40
[   28.796016]  [<ffffffff815cb1af>] ret_from_fork+0x3f/0x70
[   28.796016] Code: 48 8d 47 1c 48 89 e5 53 48 8b 37 48 89 fb 48 39 c6
74 1a 48 8b 3d 7e e9 8f 00 e8 49 fa fc ff 48 89 df e8 f1 01 fd ff 5b 5d
f3 c3 <0f> 0b 48 89 fe 48 8b 3d 61 e9 8f 00 e8 2c fa fc ff 5b 5d eb e9
[   28.796016] RIP  [<ffffffff812187b3>] putname+0x43/0x60
[   28.796016]  RSP <ffff88003592fe88>

Fixes: 193125d ("net: Introduce VRF device driver")
Signed-off-by: Nikolay Aleksandrov <[email protected]>
Acked-by: David Ahern <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
A css_set represents the relationship between a set of tasks and
css's.  css_set never pinned the associated css's.  This was okay
because tasks used to always disassociate immediately (in RCU sense) -
either a task is moved to a different css_set or exits and never
accesses css_set again.

Unfortunately, afcf6c8 ("cgroup: add cgroup_subsys->free() method
and use it to fix pids controller") and patches leading up to it made
a zombie hold onto its css_set and deref the associated css's on its
release.  Nothing pins the css's after exit and it might have already
been freed leading to use-after-free.

 general protection fault: 0000 [#1] PREEMPT SMP
 task: ffffffff81bf2500 ti: ffffffff81be4000 task.ti: ffffffff81be4000
 RIP: 0010:[<ffffffff810fa205>]  [<ffffffff810fa205>] pids_cancel.constprop.4+0x5/0x40
 ...
 Call Trace:
  <IRQ>
  [<ffffffff810fb02d>] ? pids_free+0x3d/0xa0
  [<ffffffff810f8893>] cgroup_free+0x53/0xe0
  [<ffffffff8104ed62>] __put_task_struct+0x42/0x130
  [<ffffffff81053557>] delayed_put_task_struct+0x77/0x130
  [<ffffffff810c6b34>] rcu_process_callbacks+0x2f4/0x820
  [<ffffffff810c6af3>] ? rcu_process_callbacks+0x2b3/0x820
  [<ffffffff81056e54>] __do_softirq+0xd4/0x460
  [<ffffffff81057369>] irq_exit+0x89/0xa0
  [<ffffffff81876212>] smp_apic_timer_interrupt+0x42/0x50
  [<ffffffff818747f4>] apic_timer_interrupt+0x84/0x90
  <EOI>
 ...
 Code: 5b 5d c3 48 89 df 48 c7 c2 c9 f9 ae 81 48 c7 c6 91 2c ae 81 e8 1d 94 0e 00 31 c0 5b 5d c3 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 <f0> 48 83 87 e0 00 00 00 ff 78 01 c3 80 3d 08 7a c1 00 00 74 02
 RIP  [<ffffffff810fa205>] pids_cancel.constprop.4+0x5/0x40
  RSP <ffff88001fc03e20>
 ---[ end trace 89a4a4b916b90c49 ]---
 Kernel panic - not syncing: Fatal exception in interrupt
 Kernel Offset: disabled
 ---[ end Kernel panic - not syncing: Fatal exception in interrupt

Fix it by making css_set pin the associate css's until its release.

Signed-off-by: Tejun Heo <[email protected]>
Reported-by: Dave Jones <[email protected]>
Reported-by: Daniel Wagner <[email protected]>
Link: http://lkml.kernel.org/g/[email protected]
Link: http://lkml.kernel.org/g/[email protected]
Fixes: afcf6c8 ("cgroup: add cgroup_subsys->free() method and use it to fix pids controller")
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
qdisc_tree_decrease_qlen() suffers from two problems on multiqueue
devices.

One problem is that it updates sch->q.qlen and sch->qstats.drops
on the mq/mqprio root qdisc, while it should not : Daniele
reported underflows errors :
[  681.774821] PAX: sch->q.qlen: 0 n: 1
[  681.774825] PAX: size overflow detected in function qdisc_tree_decrease_qlen net/sched/sch_api.c:769 cicus.693_49 min, count: 72, decl: qlen; num: 0; context: sk_buff_head;
[  681.774954] CPU: 2 PID: 19 Comm: ksoftirqd/2 Tainted: G           O    4.2.6.201511282239-1-grsec #1
[  681.774955] Hardware name: ASUSTeK COMPUTER INC. X302LJ/X302LJ, BIOS X302LJ.202 03/05/2015
[  681.774956]  ffffffffa9a04863 0000000000000000 0000000000000000 ffffffffa990ff7c
[  681.774959]  ffffc90000d3bc38 ffffffffa95d2810 0000000000000007 ffffffffa991002b
[  681.774960]  ffffc90000d3bc68 ffffffffa91a44f4 0000000000000001 0000000000000001
[  681.774962] Call Trace:
[  681.774967]  [<ffffffffa95d2810>] dump_stack+0x4c/0x7f
[  681.774970]  [<ffffffffa91a44f4>] report_size_overflow+0x34/0x50
[  681.774972]  [<ffffffffa94d17e2>] qdisc_tree_decrease_qlen+0x152/0x160
[  681.774976]  [<ffffffffc02694b1>] fq_codel_dequeue+0x7b1/0x820 [sch_fq_codel]
[  681.774978]  [<ffffffffc02680a0>] ? qdisc_peek_dequeued+0xa0/0xa0 [sch_fq_codel]
[  681.774980]  [<ffffffffa94cd92d>] __qdisc_run+0x4d/0x1d0
[  681.774983]  [<ffffffffa949b2b2>] net_tx_action+0xc2/0x160
[  681.774985]  [<ffffffffa90664c1>] __do_softirq+0xf1/0x200
[  681.774987]  [<ffffffffa90665ee>] run_ksoftirqd+0x1e/0x30
[  681.774989]  [<ffffffffa90896b0>] smpboot_thread_fn+0x150/0x260
[  681.774991]  [<ffffffffa9089560>] ? sort_range+0x40/0x40
[  681.774992]  [<ffffffffa9085fe4>] kthread+0xe4/0x100
[  681.774994]  [<ffffffffa9085f00>] ? kthread_worker_fn+0x170/0x170
[  681.774995]  [<ffffffffa95d8d1e>] ret_from_fork+0x3e/0x70

mq/mqprio have their own ways to report qlen/drops by folding stats on
all their queues, with appropriate locking.

A second problem is that qdisc_tree_decrease_qlen() calls qdisc_lookup()
without proper locking : concurrent qdisc updates could corrupt the list
that qdisc_match_from_root() parses to find a qdisc given its handle.

Fix first problem adding a TCQ_F_NOPARENT qdisc flag that
qdisc_tree_decrease_qlen() can use to abort its tree traversal,
as soon as it meets a mq/mqprio qdisc children.

Second problem can be fixed by RCU protection.
Qdisc are already freed after RCU grace period, so qdisc_list_add() and
qdisc_list_del() simply have to use appropriate rcu list variants.

A future patch will add a per struct netdev_queue list anchor, so that
qdisc_tree_decrease_qlen() can have more efficient lookups.

Reported-by: Daniele Fucini <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Cc: Cong Wang <[email protected]>
Cc: Jamal Hadi Salim <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
Recent PAT patchset has caused issue on 32-bit PAE machines:

  page:eea45000 count:0 mapcount:-128 mapping:  (null) index:0x0 flags: 0x40000000()
  page dumped because: VM_BUG_ON_PAGE(page_mapcount(page) < 0)
  ------------[ cut here ]------------
  kernel BUG at /home/build/linux-boris/mm/huge_memory.c:1485!
  invalid opcode: 0000 [#1] SMP
  [...]
  Call Trace:
   unmap_single_vma
   ? __wake_up
   unmap_vmas
   unmap_region
   do_munmap
   vm_munmap
   SyS_munmap
   do_fast_syscall_32
   ? __do_page_fault
   sysenter_past_esp
  Code: ...
  EIP: [<c11bde80>] zap_huge_pmd+0x240/0x260 SS:ESP 0068:f6459d98

The problem is in pmd_pfn_mask() and pmd_flags_mask(). These
helpers use PMD_PAGE_MASK to calculate resulting mask.
PMD_PAGE_MASK is 'unsigned long', not 'unsigned long long' as
phys_addr_t is on 32-bit PAE (ARCH_PHYS_ADDR_T_64BIT). As a
result, the upper bits of resulting mask get truncated.

pud_pfn_mask() and pud_flags_mask() aren't problematic since we
don't have PUD page table level on 32-bit systems, but it's
reasonable to keep them consistent with PMD counterpart.

Introduce PHYSICAL_PMD_PAGE_MASK and PHYSICAL_PUD_PAGE_MASK in
addition to existing PHYSICAL_PAGE_MASK and reworks helpers to
use them.

Reported-and-Tested-by: Boris Ostrovsky <[email protected]>
Signed-off-by: Kirill A. Shutemov <[email protected]>
[ Fix -Woverflow warnings from the realmode code. ]
Signed-off-by: Borislav Petkov <[email protected]>
Reviewed-by: Toshi Kani <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Jürgen Gross <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: linux-mm <[email protected]>
Fixes: f70abb0 ("x86/asm: Fix pud/pmd interfaces to handle large PAT bit")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

Signed-off-by: Ingo Molnar <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
introduced jbd2_write_access_granted() to improve write|undo_access
speed, but missed to check the status of b_committed_data which caused
a kernel panic on ocfs2.

[ 6538.405938] ------------[ cut here ]------------
[ 6538.406686] kernel BUG at fs/ocfs2/suballoc.c:2400!
[ 6538.406686] invalid opcode: 0000 [#1] SMP
[ 6538.406686] Modules linked in: ocfs2 nfsd lockd grace nfs_acl auth_rpcgss sunrpc autofs4 ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sd_mod sg ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 mdio ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ppdev xen_kbdfront xen_netfront xen_fbfront parport_pc parport pcspkr i2c_piix4 acpi_cpufreq ext4 jbd2 mbcache xen_blkfront floppy pata_acpi ata_generic ata_piix cirrus ttm drm_kms_helper drm fb_sys_fops sysimgblt sysfillrect i2c_core syscopyarea dm_mirror dm_region_hash dm_log dm_mod
[ 6538.406686] CPU: 1 PID: 16265 Comm: mmap_truncate Not tainted 4.3.0 #1
[ 6538.406686] Hardware name: Xen HVM domU, BIOS 4.3.1OVM 05/14/2014
[ 6538.406686] task: ffff88007c2bab00 ti: ffff880075b78000 task.ti: ffff880075b78000
[ 6538.406686] RIP: 0010:[<ffffffffa06a286b>]  [<ffffffffa06a286b>] ocfs2_block_group_clear_bits+0x23b/0x250 [ocfs2]
[ 6538.406686] RSP: 0018:ffff880075b7b7f8  EFLAGS: 00010246
[ 6538.406686] RAX: ffff8800760c5b40 RBX: ffff88006c06a000 RCX: ffffffffa06e6df0
[ 6538.406686] RDX: 0000000000000000 RSI: ffff88007a6f6ea0 RDI: ffff88007a760430
[ 6538.406686] RBP: ffff880075b7b878 R08: 0000000000000002 R09: 0000000000000001
[ 6538.406686] R10: ffffffffa06769be R11: 0000000000000000 R12: 0000000000000001
[ 6538.406686] R13: ffffffffa06a1750 R14: 0000000000000001 R15: ffff88007a6f6ea0
[ 6538.406686] FS:  00007f17fde30720(0000) GS:ffff88007f040000(0000) knlGS:0000000000000000
[ 6538.406686] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6538.406686] CR2: 0000000000601730 CR3: 000000007aea0000 CR4: 00000000000406e0
[ 6538.406686] Stack:
[ 6538.406686]  ffff88007c2bb5b0 ffff880075b7b8e0 ffff88007a7604b0 ffff88006c640800
[ 6538.406686]  ffff88007a7604b0 ffff880075d77390 0000000075b7b878 ffffffffa06a309d
[ 6538.406686]  ffff880075d752d8 ffff880075b7b990 ffff880075b7b898 0000000000000000
[ 6538.406686] Call Trace:
[ 6538.406686]  [<ffffffffa06a309d>] ? ocfs2_read_group_descriptor+0x6d/0xa0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a3654>] _ocfs2_free_suballoc_bits+0xe4/0x320 [ocfs2]
[ 6538.406686]  [<ffffffffa06a1750>] ? ocfs2_put_slot+0xf0/0xf0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a397e>] _ocfs2_free_clusters+0xee/0x210 [ocfs2]
[ 6538.406686]  [<ffffffffa06a1750>] ? ocfs2_put_slot+0xf0/0xf0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a1750>] ? ocfs2_put_slot+0xf0/0xf0 [ocfs2]
[ 6538.406686]  [<ffffffffa0682d50>] ? ocfs2_extend_trans+0x50/0x1a0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a3ad5>] ocfs2_free_clusters+0x15/0x20 [ocfs2]
[ 6538.406686]  [<ffffffffa065072c>] ocfs2_replay_truncate_records+0xfc/0x290 [ocfs2]
[ 6538.406686]  [<ffffffffa06843ac>] ? ocfs2_start_trans+0xec/0x1d0 [ocfs2]
[ 6538.406686]  [<ffffffffa0654600>] __ocfs2_flush_truncate_log+0x140/0x2d0 [ocfs2]
[ 6538.406686]  [<ffffffffa0654394>] ? ocfs2_reserve_blocks_for_rec_trunc.clone.0+0x44/0x170 [ocfs2]
[ 6538.406686]  [<ffffffffa065acd4>] ocfs2_remove_btree_range+0x374/0x630 [ocfs2]
[ 6538.406686]  [<ffffffffa017486b>] ? jbd2_journal_stop+0x25b/0x470 [jbd2]
[ 6538.406686]  [<ffffffffa065d5b5>] ocfs2_commit_truncate+0x305/0x670 [ocfs2]
[ 6538.406686]  [<ffffffffa0683430>] ? ocfs2_journal_access_eb+0x20/0x20 [ocfs2]
[ 6538.406686]  [<ffffffffa067adb7>] ocfs2_truncate_file+0x297/0x380 [ocfs2]
[ 6538.406686]  [<ffffffffa01759e4>] ? jbd2_journal_begin_ordered_truncate+0x64/0xc0 [jbd2]
[ 6538.406686]  [<ffffffffa067c7a2>] ocfs2_setattr+0x572/0x860 [ocfs2]
[ 6538.406686]  [<ffffffff810e4a3f>] ? current_fs_time+0x3f/0x50
[ 6538.406686]  [<ffffffff812124b7>] notify_change+0x1d7/0x340
[ 6538.406686]  [<ffffffff8121abf9>] ? generic_getxattr+0x79/0x80
[ 6538.406686]  [<ffffffff811f5876>] do_truncate+0x66/0x90
[ 6538.406686]  [<ffffffff81120e30>] ? __audit_syscall_entry+0xb0/0x110
[ 6538.406686]  [<ffffffff811f5bb3>] do_sys_ftruncate.clone.0+0xf3/0x120
[ 6538.406686]  [<ffffffff811f5bee>] SyS_ftruncate+0xe/0x10
[ 6538.406686]  [<ffffffff816aa2ae>] entry_SYSCALL_64_fastpath+0x12/0x71
[ 6538.406686] Code: 28 48 81 ee b0 04 00 00 48 8b 92 50 fb ff ff 48 8b 80 b0 03 00 00 48 39 90 88 00 00 00 0f 84 30 fe ff ff 0f 0b eb fe 0f 0b eb fe <0f> 0b 0f 1f 00 eb fb 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
[ 6538.406686] RIP  [<ffffffffa06a286b>] ocfs2_block_group_clear_bits+0x23b/0x250 [ocfs2]
[ 6538.406686]  RSP <ffff880075b7b7f8>
[ 6538.691128] ---[ end trace 31cd7011d6770d7e ]---
[ 6538.694492] Kernel panic - not syncing: Fatal exception
[ 6538.695484] Kernel Offset: disabled

Fixes: de92c8c("jbd2: speedup jbd2_journal_get_[write|undo]_access()")
Cc: <[email protected]>
Signed-off-by: Junxiao Bi <[email protected]>
Signed-off-by: Theodore Ts'o <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
pppoe_connect() mustn't touch the padt_work field of pppoe sockets
because that work could be already pending.

[   21.473147] BUG: unable to handle kernel NULL pointer dereference at 00000004
[   21.474523] IP: [<c1043177>] process_one_work+0x29/0x31c
[   21.475164] *pde = 00000000
[   21.475513] Oops: 0000 [#1] SMP
[   21.475910] Modules linked in: pppoe pppox ppp_generic slhc crc32c_intel aesni_intel virtio_net xts aes_i586 lrw gf128mul ablk_helper cryptd evdev acpi_cpufreq processor serio_raw button ext4 crc16 mbcache jbd2 virtio_blk virtio_pci virtio_ring virtio
[   21.476168] CPU: 2 PID: 164 Comm: kworker/2:2 Not tainted 4.4.0-rc1 #1
[   21.476168] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[   21.476168] task: f5f83c00 ti: f5e28000 task.ti: f5e28000
[   21.476168] EIP: 0060:[<c1043177>] EFLAGS: 00010046 CPU: 2
[   21.476168] EIP is at process_one_work+0x29/0x31c
[   21.484082] EAX: 00000000 EBX: f678b2a0 ECX: 00000004 EDX: 00000000
[   21.484082] ESI: f6c69940 EDI: f5e29ef0 EBP: f5e29f0c ESP: f5e29edc
[   21.484082]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[   21.484082] CR0: 80050033 CR2: 000000a4 CR3: 317ad000 CR4: 00040690
[   21.484082] Stack:
[   21.484082]  00000000 f6c69950 00000000 f6c69940 c0042338 f5e29f0c c1327945 00000000
[   21.484082]  00000008 f678b2a0 f6c69940 f678b2b8 f5e29f30 c1043984 f5f83c00 f6c69970
[   21.484082]  f678b2a0 c10437d3 f6775e80 f678b2a0 c10437d3 f5e29fac c1047059 f5e29f74
[   21.484082] Call Trace:
[   21.484082]  [<c1327945>] ? _raw_spin_lock_irq+0x28/0x30
[   21.484082]  [<c1043984>] worker_thread+0x1b1/0x244
[   21.484082]  [<c10437d3>] ? rescuer_thread+0x229/0x229
[   21.484082]  [<c10437d3>] ? rescuer_thread+0x229/0x229
[   21.484082]  [<c1047059>] kthread+0x8f/0x94
[   21.484082]  [<c1327a32>] ? _raw_spin_unlock_irq+0x22/0x26
[   21.484082]  [<c1327ee9>] ret_from_kernel_thread+0x21/0x38
[   21.484082]  [<c1046fca>] ? kthread_parkme+0x19/0x19
[   21.496082] Code: 5d c3 55 89 e5 57 56 53 89 c3 83 ec 24 89 d0 89 55 e0 8d 7d e4 e8 6c d8 ff ff b9 04 00 00 00 89 45 d8 8b 43 24 89 45 dc 8b 45 d8 <8b> 40 04 8b 80 e0 00 00 00 c1 e8 05 24 01 88 45 d7 8b 45 e0 8d
[   21.496082] EIP: [<c1043177>] process_one_work+0x29/0x31c SS:ESP 0068:f5e29edc
[   21.496082] CR2: 0000000000000004
[   21.496082] ---[ end trace e362cc9cf10dae89 ]---

Reported-by: Andrew <[email protected]>
Fixes: 287f3a9 ("pppoe: Use workqueue to die properly when a PADT is received")
Signed-off-by: Guillaume Nault <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
In a low memory situation the following kernel oops occurs:

Unable to handle kernel NULL pointer dereference at virtual address 00000050
pgd = 8490c000
[00000050] *pgd=4651e831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] PREEMPT ARM
Modules linked in:
CPU: 0    Not tainted  (3.4-at16 torvalds#9)
PC is at skb_put+0x10/0x98
LR is at sh_eth_poll+0x2c8/0xa10
pc : [<8035f780>]    lr : [<8028bf50>]    psr: 60000113
sp : 84eb1a90  ip : 84eb1ac8  fp : 84eb1ac4
r10: 0000003f  r9 : 000005ea  r8 : 00000000
r7 : 00000000  r6 : 940453b0  r5 : 00030000  r4 : 9381b180
r3 : 00000000  r2 : 00000000  r1 : 000005ea  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 4248c059  DAC: 00000015
Process klogd (pid: 2046, stack limit = 0x84eb02e8)
[...]

This is  because netdev_alloc_skb() fails and 'mdp->rx_skbuff[entry]' is left
NULL but sh_eth_rx() later  uses it without checking.  Add such check...

Reported-by: Yasushi SHOJI <[email protected]>
Signed-off-by: Sergei Shtylyov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
The Rx queue #1 frame error counter name contains trailing underscore,
probably due to a typo...

Signed-off-by: Sergei Shtylyov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
A line discipline which does not define a receive_buf() method can
can cause a GPF if data is ever received [1]. Oddly, this was known
to the author of n_tracesink in 2011, but never fixed.

[1] GPF report
    BUG: unable to handle kernel NULL pointer dereference at           (null)
    IP: [<          (null)>]           (null)
    PGD 3752d067 PUD 37a7b067 PMD 0
    Oops: 0010 [#1] SMP KASAN
    Modules linked in:
    CPU: 2 PID: 148 Comm: kworker/u10:2 Not tainted 4.4.0-rc2+ torvalds#51
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    Workqueue: events_unbound flush_to_ldisc
    task: ffff88006da94440 ti: ffff88006db60000 task.ti: ffff88006db60000
    RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
    RSP: 0018:ffff88006db67b50  EFLAGS: 00010246
    RAX: 0000000000000102 RBX: ffff88003ab32f88 RCX: 0000000000000102
    RDX: 0000000000000000 RSI: ffff88003ab330a6 RDI: ffff88003aabd388
    RBP: ffff88006db67c48 R08: ffff88003ab32f9c R09: ffff88003ab31fb0
    R10: ffff88003ab32fa8 R11: 0000000000000000 R12: dffffc0000000000
    R13: ffff88006db67c20 R14: ffffffff863df820 R15: ffff88003ab31fb8
    FS:  0000000000000000(0000) GS:ffff88006dc00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
    CR2: 0000000000000000 CR3: 0000000037938000 CR4: 00000000000006e0
    Stack:
     ffffffff829f46f1 ffff88006da94bf8 ffff88006da94bf8 0000000000000000
     ffff88003ab31fb0 ffff88003aabd438 ffff88003ab31ff8 ffff88006430fd90
     ffff88003ab32f9c ffffed0007557a87 1ffff1000db6cf78 ffff88003ab32078
    Call Trace:
     [<ffffffff8127cf91>] process_one_work+0x8f1/0x17a0 kernel/workqueue.c:2030
     [<ffffffff8127df14>] worker_thread+0xd4/0x1180 kernel/workqueue.c:2162
     [<ffffffff8128faaf>] kthread+0x1cf/0x270 drivers/block/aoe/aoecmd.c:1302
     [<ffffffff852a7c2f>] ret_from_fork+0x3f/0x70 arch/x86/entry/entry_64.S:468
    Code:  Bad RIP value.
    RIP  [<          (null)>]           (null)
     RSP <ffff88006db67b50>
    CR2: 0000000000000000
    ---[ end trace a587f8947e54d6ea ]---

Reported-by: Dmitry Vyukov <[email protected]>
Cc: <[email protected]>
Signed-off-by: Peter Hurley <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
AlbanBedel pushed a commit that referenced this issue Dec 29, 2015
Dave Jones found a warning from kasan in setup_cluster_bitmaps()

==================================================================
BUG: KASAN: stack-out-of-bounds in setup_cluster_bitmap+0xc4/0x5a0 at
addr ffff88039bef6828
Read of size 8 by task nfsd/1009
page:ffffea000e6fbd80 count:0 mapcount:0 mapping:          (null)
index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected
CPU: 1 PID: 1009 Comm: nfsd Tainted: G        W
4.4.0-rc3-backup-debug+ #1
 ffff880065647b50 000000006bb712c2 ffff88039bef6640 ffffffffa680a43e
 0000004559c00000 ffff88039bef66c8 ffffffffa62638d1 ffffffffa61121c0
 ffff8803a5769de8 0000000000000296 ffff8803a5769df0 0000000000046280
Call Trace:
 [<ffffffffa680a43e>] dump_stack+0x4b/0x6d
 [<ffffffffa62638d1>] kasan_report_error+0x501/0x520
 [<ffffffffa61121c0>] ? debug_show_all_locks+0x1e0/0x1e0
 [<ffffffffa6263948>] kasan_report+0x58/0x60
 [<ffffffffa6814b00>] ? rb_last+0x10/0x40
 [<ffffffffa66f8af4>] ? setup_cluster_bitmap+0xc4/0x5a0
 [<ffffffffa6262ead>] __asan_load8+0x5d/0x70
 [<ffffffffa66f8af4>] setup_cluster_bitmap+0xc4/0x5a0
 [<ffffffffa66f675a>] ? setup_cluster_no_bitmap+0x6a/0x400
 [<ffffffffa66fcd16>] btrfs_find_space_cluster+0x4b6/0x640
 [<ffffffffa66fc860>] ? btrfs_alloc_from_cluster+0x4e0/0x4e0
 [<ffffffffa66fc36e>] ? btrfs_return_cluster_to_free_space+0x9e/0xb0
 [<ffffffffa702dc37>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffffa666a1a1>] find_free_extent+0xba1/0x1520

Andrey noticed this was because we were doing list_first_entry on a list
that might be empty.  Rework the tests a bit so we don't do that.

Signed-off-by: Chris Mason <[email protected]>
Reprorted-by: Andrey Ryabinin <[email protected]>
Reported-by:  Dave Jones <[email protected]>
AlbanBedel pushed a commit that referenced this issue Feb 18, 2016
… switches

If cgroup writeback is in use, an inode is associated with a cgroup
for writeback.  If the inode's main dirtier changes to another cgroup,
the association gets updated asynchronously.  Nothing was pinning the
superblock while such switches are in progress and superblock could go
away while async switching is pending or in progress leading to
crashes like the following.

 kernel BUG at fs/jbd2/transaction.c:319!
 invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
 CPU: 1 PID: 29158 Comm: kworker/1:10 Not tainted 4.5.0-rc3 torvalds#51
 Hardware name: Google Google, BIOS Google 01/01/2011
 Workqueue: events inode_switch_wbs_work_fn
 task: ffff880213dbbd40 ti: ffff880209264000 task.ti: ffff880209264000
 RIP: 0010:[<ffffffff803e6922>]  [<ffffffff803e6922>] start_this_handle+0x382/0x3e0
 RSP: 0018:ffff880209267c30  EFLAGS: 00010202
 ...
 Call Trace:
  [<ffffffff803e6be4>] jbd2__journal_start+0xf4/0x190
  [<ffffffff803cfc7e>] __ext4_journal_start_sb+0x4e/0x70
  [<ffffffff803b31ec>] ext4_evict_inode+0x12c/0x3d0
  [<ffffffff8035338b>] evict+0xbb/0x190
  [<ffffffff80354190>] iput+0x130/0x190
  [<ffffffff80360223>] inode_switch_wbs_work_fn+0x343/0x4c0
  [<ffffffff80279819>] process_one_work+0x129/0x300
  [<ffffffff80279b16>] worker_thread+0x126/0x480
  [<ffffffff8027ed14>] kthread+0xc4/0xe0
  [<ffffffff809771df>] ret_from_fork+0x3f/0x70

Fix it by bumping s_active while cgroup association switching is in
flight.

Signed-off-by: Tejun Heo <[email protected]>
Reported-and-tested-by: Tahsin Erdogan <[email protected]>
Link: http://lkml.kernel.org/g/CAAeU0aNCq7LGODvVGRU-oU_o-6enii5ey0p1c26D1ZzYwkDc5A@mail.gmail.com
Fixes: d10c809 ("writeback: implement foreign cgroup inode bdi_writeback switching")
Cc: [email protected] #v4.5+
Signed-off-by: Jens Axboe <[email protected]>
AlbanBedel pushed a commit that referenced this issue Feb 20, 2016
This softlockup is currently happening:

[  444.088002] NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [kworker/1:1:29]
[  444.088002] Modules linked in: lpfc(-) qla2x00tgt(O) qla2xxx_scst(O) scst_vdisk(O) scsi_transport_fc libcrc32c scst(O) dlm configfs nfsd lockd grace nfs_acl auth_rpcgss sunrpc ed
d snd_pcm_oss snd_mixer_oss snd_seq snd_seq_device dm_mod iTCO_wdt snd_hda_codec_realtek snd_hda_codec_generic gpio_ich iTCO_vendor_support ppdev snd_hda_intel snd_hda_codec snd_hda
_core snd_hwdep tg3 snd_pcm snd_timer libphy lpc_ich parport_pc ptp acpi_cpufreq snd pps_core fjes parport i2c_i801 ehci_pci tpm_tis tpm sr_mod cdrom soundcore floppy hwmon sg 8250_
fintek pcspkr i915 drm_kms_helper uhci_hcd ehci_hcd drm fb_sys_fops sysimgblt sysfillrect syscopyarea i2c_algo_bit usbcore button video usb_common fan ata_generic ata_piix libata th
ermal
[  444.088002] CPU: 1 PID: 29 Comm: kworker/1:1 Tainted: G           O    4.4.0-rc5-2.g1e923a3-default #1
[  444.088002] Hardware name: FUJITSU SIEMENS ESPRIMO E           /D2164-A1, BIOS 5.00 R1.10.2164.A1               05/08/2006
[  444.088002] Workqueue: fc_wq_4 fc_rport_final_delete [scsi_transport_fc]
[  444.088002] task: f6266ec0 ti: f6268000 task.ti: f6268000
[  444.088002] EIP: 0060:[<c07e7044>] EFLAGS: 00000286 CPU: 1
[  444.088002] EIP is at _raw_spin_unlock_irqrestore+0x14/0x20
[  444.088002] EAX: 00000286 EBX: f20d3800 ECX: 00000002 EDX: 00000286
[  444.088002] ESI: f50ba800 EDI: f2146848 EBP: f6269ec8 ESP: f6269ec8
[  444.088002]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
[  444.088002] CR0: 8005003b CR2: 08f96600 CR3: 363ae000 CR4: 000006d0
[  444.088002] Stack:
[  444.088002]  f6269eec c066b0f7 00000286 f2146848 f50ba808 f50ba800 f50ba800 f2146a90
[  444.088002]  f2146848 f6269f08 f8f0a4ed f3141000 f2146800 f2146a90 f619fa00 00000040
[  444.088002]  f6269f40 c026cb25 00000001 166c6392 00000061 f6757140 f6136340 00000004
[  444.088002] Call Trace:
[  444.088002]  [<c066b0f7>] scsi_remove_target+0x167/0x1c0
[  444.088002]  [<f8f0a4ed>] fc_rport_final_delete+0x9d/0x1e0 [scsi_transport_fc]
[  444.088002]  [<c026cb25>] process_one_work+0x155/0x3e0
[  444.088002]  [<c026cde7>] worker_thread+0x37/0x490
[  444.088002]  [<c027214b>] kthread+0x9b/0xb0
[  444.088002]  [<c07e72c1>] ret_from_kernel_thread+0x21/0x40

What appears to be happening is that something has pinned the target
so it can't go into STARGET_DEL via final release and the loop in
scsi_remove_target spins endlessly until that happens.

The fix for this soft lockup is to not keep looping over a device that
we've called remove on but which hasn't gone into DEL state.  This
patch will retain a simplistic memory of the last target and not keep
looping over it.

Reported-by: Sebastian Herbszt <[email protected]>
Tested-by: Sebastian Herbszt <[email protected]>
Fixes: 4099819
Cc: [email protected]
Signed-off-by: James Bottomley <[email protected]>
AlbanBedel pushed a commit that referenced this issue Feb 20, 2016
When slub_debug alloc_calls_show is enabled we will try to track
location and user of slab object on each online node, kmem_cache_node
structure and cpu_cache/cpu_slub shouldn't be freed till there is the
last reference to sysfs file.

This fixes the following panic:

   BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
   IP:  list_locations+0x169/0x4e0
   PGD 257304067 PUD 438456067 PMD 0
   Oops: 0000 [#1] SMP
   CPU: 3 PID: 973074 Comm: cat ve: 0 Not tainted 3.10.0-229.7.2.ovz.9.30-00007-japdoll-dirty #2 9.30
   Hardware name: DEPO Computers To Be Filled By O.E.M./H67DE3, BIOS L1.60c 07/14/2011
   task: ffff88042a5dc5b0 ti: ffff88037f8d8000 task.ti: ffff88037f8d8000
   RIP: list_locations+0x169/0x4e0
   Call Trace:
     alloc_calls_show+0x1d/0x30
     slab_attr_show+0x1b/0x30
     sysfs_read_file+0x9a/0x1a0
     vfs_read+0x9c/0x170
     SyS_read+0x58/0xb0
     system_call_fastpath+0x16/0x1b
   Code: 5e 07 12 00 b9 00 04 00 00 3d 00 04 00 00 0f 4f c1 3d 00 04 00 00 89 45 b0 0f 84 c3 00 00 00 48 63 45 b0 49 8b 9c c4 f8 00 00 00 <48> 8b 43 20 48 85 c0 74 b6 48 89 df e8 46 37 44 00 48 8b 53 10
   CR2: 0000000000000020

Separated __kmem_cache_release from __kmem_cache_shutdown which now
called on slab_kmem_cache_release (after the last reference to sysfs
file object has dropped).

Reintroduced locking in free_partial as sysfs file might access cache's
partial list after shutdowning - partial revert of the commit
69cb8e6 ("slub: free slabs without holding locks").  Zap
__remove_partial and use remove_partial (w/o underscores) as
free_partial now takes list_lock which s partial revert for commit
1e4dd94 ("slub: do not assert not having lock in removing freed
partial")

Signed-off-by: Dmitry Safonov <[email protected]>
Suggested-by: Vladimir Davydov <[email protected]>
Acked-by: Vladimir Davydov <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
@AlbanBedel
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It turns out most mips platform don't have any prefix, so that's probably not worth the mess to change this.

AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
syzkaller reported a crash in ata_bmdma_fill_sg() when writing to
/dev/sg1.  The immediate cause was that the ATA command's scatterlist
was not DMA-mapped, which causes 'pi - 1' to underflow, resulting in a
write to 'qc->ap->bmdma_prd[0xffffffff]'.

Strangely though, the flag ATA_QCFLAG_DMAMAP was set in qc->flags.  The
root cause is that when __ata_scsi_queuecmd() is preparing to relay a
SCSI command to an ATAPI device, it doesn't correctly validate the CDB
length before copying it into the 16-byte buffer 'cdb' in 'struct
ata_queued_cmd'.  Namely, it validates the fixed CDB length expected
based on the SCSI opcode but not the actual CDB length, which can be
larger due to the use of the SG_NEXT_CMD_LEN ioctl.  Since 'flags' is
the next member in ata_queued_cmd, a buffer overflow corrupts it.

Fix it by requiring that the actual CDB length be <= 16 (ATAPI_CDB_LEN).

[Really it seems the length should be required to be <= dev->cdb_len,
but the current behavior seems to have been intentionally introduced by
commit 607126c ("libata-scsi: be tolerant of 12-byte ATAPI commands
in 16-byte CDBs") to work around a userspace bug in mplayer.  Probably
the workaround is no longer needed (mplayer was fixed in 2007), but
continuing to allow lengths to up 16 appears harmless for now.]

Here's a reproducer that works in QEMU when /dev/sg1 refers to the
CD-ROM drive that qemu-system-x86_64 creates by default:

    #include <fcntl.h>
    #include <sys/ioctl.h>
    #include <unistd.h>

    #define SG_NEXT_CMD_LEN 0x2283

    int main()
    {
	    char buf[53] = { [36] = 0x7e, [52] = 0x02 };
	    int fd = open("/dev/sg1", O_RDWR);
	    ioctl(fd, SG_NEXT_CMD_LEN, &(int){ 17 });
	    write(fd, buf, sizeof(buf));
    }

The crash was:

    BUG: unable to handle kernel paging request at ffff8cb97db37ffc
    IP: ata_bmdma_fill_sg drivers/ata/libata-sff.c:2623 [inline]
    IP: ata_bmdma_qc_prep+0xa4/0xc0 drivers/ata/libata-sff.c:2727
    PGD fb6c067 P4D fb6c067 PUD 0
    Oops: 0002 [#1] SMP
    CPU: 1 PID: 150 Comm: syz_ata_bmdma_q Not tainted 4.15.0-next-20180202 torvalds#99
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
    [...]
    Call Trace:
     ata_qc_issue+0x100/0x1d0 drivers/ata/libata-core.c:5421
     ata_scsi_translate+0xc9/0x1a0 drivers/ata/libata-scsi.c:2024
     __ata_scsi_queuecmd drivers/ata/libata-scsi.c:4326 [inline]
     ata_scsi_queuecmd+0x8c/0x210 drivers/ata/libata-scsi.c:4375
     scsi_dispatch_cmd+0xa2/0xe0 drivers/scsi/scsi_lib.c:1727
     scsi_request_fn+0x24c/0x530 drivers/scsi/scsi_lib.c:1865
     __blk_run_queue_uncond block/blk-core.c:412 [inline]
     __blk_run_queue+0x3a/0x60 block/blk-core.c:432
     blk_execute_rq_nowait+0x93/0xc0 block/blk-exec.c:78
     sg_common_write.isra.7+0x272/0x5a0 drivers/scsi/sg.c:806
     sg_write+0x1ef/0x340 drivers/scsi/sg.c:677
     __vfs_write+0x31/0x160 fs/read_write.c:480
     vfs_write+0xa7/0x160 fs/read_write.c:544
     SYSC_write fs/read_write.c:589 [inline]
     SyS_write+0x4d/0xc0 fs/read_write.c:581
     do_syscall_64+0x5e/0x110 arch/x86/entry/common.c:287
     entry_SYSCALL_64_after_hwframe+0x21/0x86

Fixes: 607126c ("libata-scsi: be tolerant of 12-byte ATAPI commands in 16-byte CDBs")
Reported-by: syzbot+1ff6f9fcc3c35f1c72a95e26528c8e7e3276e4da@syzkaller.appspotmail.com
Cc: <[email protected]> # v2.6.24+
Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Since commit 59dc3d8 ("clk: imx51: uart4, uart5 gates only exist on
imx50, imx53") the following warnings are seen on i.MX53:

[    2.776190] ------------[ cut here ]------------
[    2.780948] WARNING: CPU: 0 PID: 1 at ../drivers/clk/clk.c:811 clk_core_disable+0xc4/0xe0
[    2.789145] Modules linked in:
[    2.792236] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc7-next-20180115 #1
[    2.799735] Hardware name: Freescale i.MX53 (Device Tree Support)
[    2.805845] Backtrace:
[    2.808329] [<c010d1a0>] (dump_backtrace) from [<c010d460>] (show_stack+0x18/0x1c)
[    2.815919]  r7:00000000 r6:60000093 r5:00000000 r4:c10798d4
[    2.821607] [<c010d448>] (show_stack) from [<c0a353ec>] (dump_stack+0xb4/0xe8)
[    2.828854] [<c0a35338>] (dump_stack) from [<c0126144>] (__warn+0xf0/0x11c)
[    2.835837]  r9:00000000 r8:0000032b r7:00000009 r6:c0d429f8 r5:00000000 r4:00000000
[    2.843601] [<c0126054>] (__warn) from [<c0126288>] (warn_slowpath_null+0x44/0x50)
[    2.851191]  r8:c1008908 r7:c0e08874 r6:c04bfac8 r5:0000032b r4:c0d429f8
[    2.857913] [<c0126244>] (warn_slowpath_null) from [<c04bfac8>] (clk_core_disable+0xc4/0xe0)
[    2.866369]  r6:dc02bb00 r5:dc02a980 r4:dc02a980
[    2.871011] [<c04bfa04>] (clk_core_disable) from [<c04c0e54>] (clk_core_disable_lock+0x20/0x2c)
[    2.879726]  r5:dc02a980 r4:80000013
[    2.883323] [<c04c0e34>] (clk_core_disable_lock) from [<c04c0e84>] (clk_disable+0x24/0x28)
[    2.891604]  r5:c0f6b3e4 r4:0000001c
[    2.895209] [<c04c0e60>] (clk_disable) from [<c0f2340c>] (imx_clk_disable_uart+0x50/0x68)
[    2.903412] [<c0f233bc>] (imx_clk_disable_uart) from [<c010277c>] (do_one_initcall+0x50/0x19c)
[    2.912043]  r7:c0e08874 r6:c0f63854 r5:c0f233bc r4:ffffe000
[    2.917726] [<c010272c>] (do_one_initcall) from [<c0f00f00>] (kernel_init_freeable+0x118/0x1d0)
[    2.926447]  r9:c0f63858 r8:000000f0 r7:c0e08874 r6:c0f63854 r5:c107b500 r4:c0f75260
[    2.934220] [<c0f00de8>] (kernel_init_freeable) from [<c0a4a5f0>] (kernel_init+0x10/0x118)
[    2.942506]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0a4a5e0
[    2.950351]  r4:00000000
[    2.952908] [<c0a4a5e0>] (kernel_init) from [<c01010b4>] (ret_from_fork+0x14/0x20)
[    2.960496] Exception stack(0xdc05dfb0 to 0xdc05dff8)
[    2.965569] dfa0:                                     00000000 00000000 00000000 00000000
[    2.973768] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    2.981965] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    2.988596]  r5:c0a4a5e0 r4:00000000
[    2.992188] ---[ end trace 346e26f708876edd ]---
[    2.997420] ------------[ cut here ]------------

In order to fix the problem UART4/5 registration needs to happen only on
i.MX50 and i.MX53.

So let mx51_clocks_init() register only UART1-3 and
mx50_clocks_init()/mx53_clocks_init register all the UART1-5 ports.

Fixes: 59dc3d8 ("clk: imx51: uart4, uart5 gates only exist on imx50, imx53")
Signed-off-by: Fabio Estevam <[email protected]>
Reviewed-by: Philipp Zabel <[email protected]>
Signed-off-by: Shawn Guo <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
We've got a kernel panic when using sata disk with sas controller:

[115946.152283] Unable to handle kernel NULL pointer dereference at virtual address 000007d8
[115946.223963] CPU: 0 PID: 22175 Comm: kworker/0:1 Tainted: G   W OEL  4.14.0 #1
[115946.232925] Workqueue: events ata_scsi_hotplug
[115946.237938] task: ffff8021ee50b180 task.stack: ffff00000d5d0000
[115946.244717] PC is at sas_find_dev_by_rphy+0x44/0x114
[115946.250224] LR is at sas_find_dev_by_rphy+0x3c/0x114
......
[115946.355701] Process kworker/0:1 (pid: 22175, stack limit = 0xffff00000d5d0000)
[115946.363369] Call trace:
[115946.456356] [<ffff000008878a9c>] sas_find_dev_by_rphy+0x44/0x114
[115946.462908] [<ffff000008878b8c>] sas_target_alloc+0x20/0x5c
[115946.469408] [<ffff00000885a31c>] scsi_alloc_target+0x250/0x308
[115946.475781] [<ffff00000885ba30>] __scsi_add_device+0xb0/0x154
[115946.481991] [<ffff0000088b520c>] ata_scsi_scan_host+0x180/0x218
[115946.488367] [<ffff0000088b53d8>] ata_scsi_hotplug+0xb0/0xcc
[115946.494801] [<ffff0000080ebd70>] process_one_work+0x144/0x390
[115946.501115] [<ffff0000080ec100>] worker_thread+0x144/0x418
[115946.507093] [<ffff0000080f2c98>] kthread+0x10c/0x138
[115946.512792] [<ffff0000080855dc>] ret_from_fork+0x10/0x18

We found that Ding Xiang has reported a similar bug before:
https://patchwork.kernel.org/patch/9179817/

And this bug still exists in mainline. Since libsas handles hotplug and
device adding/removing itself, do not need to schedule ata hot plug task
here if it is a sas host.

Signed-off-by: Jason Yan <[email protected]>
Cc: Ding Xiang <[email protected]>
Cc: [email protected]
Signed-off-by: Tejun Heo <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Currently we can crash perf record when running in pipe mode, like:

  $ perf record ls | perf report
  # To display the perf.data header info, please use --header/--header-only options.
  #
  perf: Segmentation fault
  Error:
  The - file has no samples!

The callstack of the crash is:

    0x0000000000515242 in perf_event__synthesize_event_update_name
  3513            ev = event_update_event__new(len + 1, PERF_EVENT_UPDATE__NAME, evsel->id[0]);
  (gdb) bt
  #0  0x0000000000515242 in perf_event__synthesize_event_update_name
  #1  0x00000000005158a4 in perf_event__synthesize_extra_attr
  #2  0x0000000000443347 in record__synthesize
  #3  0x00000000004438e3 in __cmd_record
  #4  0x000000000044514e in cmd_record
  #5  0x00000000004cbc95 in run_builtin
  torvalds#6  0x00000000004cbf02 in handle_internal_command
  torvalds#7  0x00000000004cc054 in run_argv
  torvalds#8  0x00000000004cc422 in main

The reason of the crash is that the evsel does not have ids array
allocated and the pipe's synthesize code tries to access it.

We don't force evsel ids allocation when we have single event, because
it's not needed. However we need it when we are in pipe mode even for
single event as a key for evsel update event.

Fixing this by forcing evsel ids allocation event for single event, when
we are in pipe mode.

Signed-off-by: Jiri Olsa <[email protected]>
Tested-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Corsair Strafe RGB keyboard does not respond to usb control messages
sometimes and hence generates timeouts.

Commit de3af5b ("usb: quirks: add delay init quirk for Corsair
Strafe RGB keyboard") tried to fix those timeouts by adding
USB_QUIRK_DELAY_INIT.

Unfortunately, even with this quirk timeouts of usb_control_msg()
can still be seen, but with a lower frequency (approx. 1 out of 15):

[   29.103520] usb 1-8: string descriptor 0 read error: -110
[   34.363097] usb 1-8: can't set config #1, error -110

Adding further delays to different locations where usb control
messages are issued just moves the timeouts to other locations,
e.g.:

[   35.400533] usbhid 1-8:1.0: can't add hid device: -110
[   35.401014] usbhid: probe of 1-8:1.0 failed with error -110

The only way to reliably avoid those issues is having a pause after
each usb control message. In approx. 200 boot cycles no more timeouts
were seen.

Addionaly, keep USB_QUIRK_DELAY_INIT as it turned out to be necessary
to have the delay in hub_port_connect() after hub_port_init().

The overall boot time seems not to be influenced by these additional
delays, even on fast machines and lightweight distributions.

Fixes: de3af5b ("usb: quirks: add delay init quirk for Corsair Strafe RGB keyboard")
Cc: [email protected]
Signed-off-by: Danilo Krummrich <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
__dev_mc_add grabs an adress spinlock so use
atomic context in kmalloc.

/ # ifconfig eth0 inet 192.168.0.111
[   89.331622] BUG: sleeping function called from invalid context at mm/slab.h:420
[   89.339002] in_atomic(): 1, irqs_disabled(): 0, pid: 1035, name: ifconfig
[   89.345799] 2 locks held by ifconfig/1035:
[   89.349908]  #0:  (rtnl_mutex){+.+.}, at: [<(ptrval)>] devinet_ioctl+0xc0/0x8a0
[   89.357258]  #1:  (_xmit_ETHER){+...}, at: [<(ptrval)>] __dev_mc_add+0x28/0x80
[   89.364520] CPU: 1 PID: 1035 Comm: ifconfig Not tainted 4.16.0-rc3-dirty torvalds#8
[   89.371464] Call Trace:
[   89.373908] [e959db60] [c066f948] dump_stack+0xa4/0xfc (unreliable)
[   89.380177] [e959db80] [c00671d8] ___might_sleep+0x248/0x280
[   89.385833] [e959dba0] [c01aec34] kmem_cache_alloc_trace+0x174/0x320
[   89.392179] [e959dbd0] [c04ab920] dtsec_add_hash_mac_address+0x130/0x240
[   89.398874] [e959dc00] [c04a9d74] set_multi+0x174/0x1b0
[   89.404093] [e959dc30] [c04afb68] dpaa_set_rx_mode+0x68/0xe0
[   89.409745] [e959dc40] [c057baf8] __dev_mc_add+0x58/0x80
[   89.415052] [e959dc60] [c060fd64] igmp_group_added+0x164/0x190
[   89.420878] [e959dca0] [c060ffa8] ip_mc_inc_group+0x218/0x460
[   89.426617] [e959dce0] [c06120fc] ip_mc_up+0x3c/0x190
[   89.431662] [e959dd10] [c0607270] inetdev_event+0x250/0x620
[   89.437227] [e959dd50] [c005f190] notifier_call_chain+0x80/0xf0
[   89.443138] [e959dd80] [c0573a74] __dev_notify_flags+0x54/0xf0
[   89.448964] [e959dda0] [c05743f8] dev_change_flags+0x48/0x60
[   89.454615] [e959ddc0] [c0606744] devinet_ioctl+0x544/0x8a0
[   89.460180] [e959de10] [c060987c] inet_ioctl+0x9c/0x1f0
[   89.465400] [e959de80] [c05479a8] sock_ioctl+0x168/0x460
[   89.470708] [e959ded0] [c01cf3ec] do_vfs_ioctl+0xac/0x8c0
[   89.476099] [e959df20] [c01cfc40] SyS_ioctl+0x40/0xc0
[   89.481147] [e959df40] [c0011318] ret_from_syscall+0x0/0x3c
[   89.486715] --- interrupt: c01 at 0x1006943c
[   89.486715]     LR = 0x100c45ec

Signed-off-by: Denis Kirjanov <[email protected]>
Acked-by: Madalin Bucur <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
When running rcutorture with TREE03 config, CONFIG_PROVE_LOCKING=y, and
kernel cmdline argument "rcutorture.gp_exp=1", lockdep reports a
HARDIRQ-safe->HARDIRQ-unsafe deadlock:

 ================================
 WARNING: inconsistent lock state
 4.16.0-rc4+ #1 Not tainted
 --------------------------------
 inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
 takes:
 __schedule+0xbe/0xaf0
 {IN-HARDIRQ-W} state was registered at:
   _raw_spin_lock+0x2a/0x40
   scheduler_tick+0x47/0xf0
...
 other info that might help us debug this:
  Possible unsafe locking scenario:
        CPU0
        ----
   lock(&rq->lock);
   <Interrupt>
     lock(&rq->lock);
  *** DEADLOCK ***
 1 lock held by rcu_torture_rea/724:
 rcu_torture_read_lock+0x0/0x70
 stack backtrace:
 CPU: 2 PID: 724 Comm: rcu_torture_rea Not tainted 4.16.0-rc4+ #1
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
 Call Trace:
  lock_acquire+0x90/0x200
  ? __schedule+0xbe/0xaf0
  _raw_spin_lock+0x2a/0x40
  ? __schedule+0xbe/0xaf0
  __schedule+0xbe/0xaf0
  preempt_schedule_irq+0x2f/0x60
  retint_kernel+0x1b/0x2d
 RIP: 0010:rcu_read_unlock_special+0x0/0x680
  ? rcu_torture_read_unlock+0x60/0x60
  __rcu_read_unlock+0x64/0x70
  rcu_torture_read_unlock+0x17/0x60
  rcu_torture_reader+0x275/0x450
  ? rcutorture_booster_init+0x110/0x110
  ? rcu_torture_stall+0x230/0x230
  ? kthread+0x10e/0x130
  kthread+0x10e/0x130
  ? kthread_create_worker_on_cpu+0x70/0x70
  ? call_usermodehelper_exec_async+0x11a/0x150
  ret_from_fork+0x3a/0x50

This happens with the following even sequence:

	preempt_schedule_irq();
	  local_irq_enable();
	  __schedule():
	    local_irq_disable(); // irq off
	    ...
	    rcu_note_context_switch():
	      rcu_note_preempt_context_switch():
	        rcu_read_unlock_special():
	          local_irq_save(flags);
	          ...
		  raw_spin_unlock_irqrestore(...,flags); // irq remains off
	          rt_mutex_futex_unlock():
	            raw_spin_lock_irq();
	            ...
	            raw_spin_unlock_irq(); // accidentally set irq on

	    <return to __schedule()>
	    rq_lock():
	      raw_spin_lock(); // acquiring rq->lock with irq on

which means rq->lock becomes a HARDIRQ-unsafe lock, which can cause
deadlocks in scheduler code.

This problem was introduced by commit 02a7c23 ("rcu: Suppress
lockdep false-positive ->boost_mtx complaints"). That brought the user
of rt_mutex_futex_unlock() with irq off.

To fix this, replace the *lock_irq() in rt_mutex_futex_unlock() with
*lock_irq{save,restore}() to make it safe to call rt_mutex_futex_unlock()
with irq off.

Fixes: 02a7c23 ("rcu: Suppress lockdep false-positive ->boost_mtx complaints")
Signed-off-by: Boqun Feng <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: "Paul E . McKenney" <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
The failure in rereg_mr flow caused to set garbage value (error value)
into mr->umem pointer. This pointer is accessed at the release stage
and it causes to the following crash.

There is not enough to simply change umem to point to NULL, because the
MR struct is needed to be accessed during MR deregistration phase, so
delay kfree too.

[    6.237617] BUG: unable to handle kernel NULL pointer dereference a 0000000000000228
[    6.238756] IP: ib_dereg_mr+0xd/0x30
[    6.239264] PGD 80000000167eb067 P4D 80000000167eb067 PUD 167f9067 PMD 0
[    6.240320] Oops: 0000 [#1] SMP PTI
[    6.240782] CPU: 0 PID: 367 Comm: dereg Not tainted 4.16.0-rc1-00029-gc198fafe0453 torvalds#183
[    6.242120] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[    6.244504] RIP: 0010:ib_dereg_mr+0xd/0x30
[    6.245253] RSP: 0018:ffffaf5d001d7d68 EFLAGS: 00010246
[    6.246100] RAX: 0000000000000000 RBX: ffff95d4172daf00 RCX: 0000000000000000
[    6.247414] RDX: 00000000ffffffff RSI: 0000000000000001 RDI: ffff95d41a317600
[    6.248591] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
[    6.249810] R10: ffff95d417033c10 R11: 0000000000000000 R12: ffff95d4172c3a80
[    6.251121] R13: ffff95d4172c3720 R14: ffff95d4172c3a98 R15: 00000000ffffffff
[    6.252437] FS:  0000000000000000(0000) GS:ffff95d41fc00000(0000) knlGS:0000000000000000
[    6.253887] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    6.254814] CR2: 0000000000000228 CR3: 00000000172b4000 CR4: 00000000000006b0
[    6.255943] Call Trace:
[    6.256368]  remove_commit_idr_uobject+0x1b/0x80
[    6.257118]  uverbs_cleanup_ucontext+0xe4/0x190
[    6.257855]  ib_uverbs_cleanup_ucontext.constprop.14+0x19/0x40
[    6.258857]  ib_uverbs_close+0x2a/0x100
[    6.259494]  __fput+0xca/0x1c0
[    6.259938]  task_work_run+0x84/0xa0
[    6.260519]  do_exit+0x312/0xb40
[    6.261023]  ? __do_page_fault+0x24d/0x490
[    6.261707]  do_group_exit+0x3a/0xa0
[    6.262267]  SyS_exit_group+0x10/0x10
[    6.262802]  do_syscall_64+0x75/0x180
[    6.263391]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[    6.264253] RIP: 0033:0x7f1b39c49488
[    6.264827] RSP: 002b:00007ffe2de05b68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[    6.266049] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1b39c49488
[    6.267187] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
[    6.268377] RBP: 00007f1b39f258e0 R08: 00000000000000e7 R09: ffffffffffffff98
[    6.269640] R10: 00007f1b3a147260 R11: 0000000000000246 R12: 00007f1b39f258e0
[    6.270783] R13: 00007f1b39f2ac20 R14: 0000000000000000 R15: 0000000000000000
[    6.271943] Code: 74 07 31 d2 e9 25 d8 6c 00 b8 da ff ff ff c3 0f 1f
44 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 8b 07 53 48 8b
5f 08 <48> 8b 80 28 02 00 00 e8 f7 d7 6c 00 85 c0 75 04 3e ff 4b 18 5b
[    6.274927] RIP: ib_dereg_mr+0xd/0x30 RSP: ffffaf5d001d7d68
[    6.275760] CR2: 0000000000000228
[    6.276200] ---[ end trace a35641f1c474bd20 ]---

Fixes: e126ba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Cc: syzkaller <[email protected]>
Cc: <[email protected]>
Reported-by: Noa Osherovich <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
The attempt to join multicast group without ensuring that CMA device
exists will lead to the following crash reported by syzkaller.

[   64.076794] BUG: KASAN: null-ptr-deref in rdma_join_multicast+0x26e/0x12c0
[   64.076797] Read of size 8 at addr 00000000000000b0 by task join/691
[   64.076797]
[   64.076800] CPU: 1 PID: 691 Comm: join Not tainted 4.16.0-rc1-00219-gb97853b65b93 torvalds#23
[   64.076802] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-proj4
[   64.076803] Call Trace:
[   64.076809]  dump_stack+0x5c/0x77
[   64.076817]  kasan_report+0x163/0x380
[   64.085859]  ? rdma_join_multicast+0x26e/0x12c0
[   64.086634]  rdma_join_multicast+0x26e/0x12c0
[   64.087370]  ? rdma_disconnect+0xf0/0xf0
[   64.088579]  ? __radix_tree_replace+0xc3/0x110
[   64.089132]  ? node_tag_clear+0x81/0xb0
[   64.089606]  ? idr_alloc_u32+0x12e/0x1a0
[   64.090517]  ? __fprop_inc_percpu_max+0x150/0x150
[   64.091768]  ? tracing_record_taskinfo+0x10/0xc0
[   64.092340]  ? idr_alloc+0x76/0xc0
[   64.092951]  ? idr_alloc_u32+0x1a0/0x1a0
[   64.093632]  ? ucma_process_join+0x23d/0x460
[   64.094510]  ucma_process_join+0x23d/0x460
[   64.095199]  ? ucma_migrate_id+0x440/0x440
[   64.095696]  ? futex_wake+0x10b/0x2a0
[   64.096159]  ucma_join_multicast+0x88/0xe0
[   64.096660]  ? ucma_process_join+0x460/0x460
[   64.097540]  ? _copy_from_user+0x5e/0x90
[   64.098017]  ucma_write+0x174/0x1f0
[   64.098640]  ? ucma_resolve_route+0xf0/0xf0
[   64.099343]  ? rb_erase_cached+0x6c7/0x7f0
[   64.099839]  __vfs_write+0xc4/0x350
[   64.100622]  ? perf_syscall_enter+0xe4/0x5f0
[   64.101335]  ? kernel_read+0xa0/0xa0
[   64.103525]  ? perf_sched_cb_inc+0xc0/0xc0
[   64.105510]  ? syscall_exit_register+0x2a0/0x2a0
[   64.107359]  ? __switch_to+0x351/0x640
[   64.109285]  ? fsnotify+0x899/0x8f0
[   64.111610]  ? fsnotify_unmount_inodes+0x170/0x170
[   64.113876]  ? __fsnotify_update_child_dentry_flags+0x30/0x30
[   64.115813]  ? ring_buffer_record_is_on+0xd/0x20
[   64.117824]  ? __fget+0xa8/0xf0
[   64.119869]  vfs_write+0xf7/0x280
[   64.122001]  SyS_write+0xa1/0x120
[   64.124213]  ? SyS_read+0x120/0x120
[   64.126644]  ? SyS_read+0x120/0x120
[   64.128563]  do_syscall_64+0xeb/0x250
[   64.130732]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[   64.132984] RIP: 0033:0x7f5c994ade99
[   64.135699] RSP: 002b:00007f5c99b97d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   64.138740] RAX: ffffffffffffffda RBX: 00000000200001e4 RCX: 00007f5c994ade99
[   64.141056] RDX: 00000000000000a0 RSI: 00000000200001c0 RDI: 0000000000000015
[   64.143536] RBP: 00007f5c99b97ec0 R08: 0000000000000000 R09: 0000000000000000
[   64.146017] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5c99b97fc0
[   64.148608] R13: 0000000000000000 R14: 00007fff660e1c40 R15: 00007f5c99b989c0
[   64.151060]
[   64.153703] Disabling lock debugging due to kernel taint
[   64.156032] BUG: unable to handle kernel NULL pointer dereference at 00000000000000b0
[   64.159066] IP: rdma_join_multicast+0x26e/0x12c0
[   64.161451] PGD 80000001d0298067 P4D 80000001d0298067 PUD 1dea39067 PMD 0
[   64.164442] Oops: 0000 [#1] SMP KASAN PTI
[   64.166817] CPU: 1 PID: 691 Comm: join Tainted: G    B 4.16.0-rc1-00219-gb97853b65b93 torvalds#23
[   64.170004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-proj4
[   64.174985] RIP: 0010:rdma_join_multicast+0x26e/0x12c0
[   64.177246] RSP: 0018:ffff8801c8207860 EFLAGS: 00010282
[   64.179901] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff94789522
[   64.183344] RDX: 1ffffffff2d50fa5 RSI: 0000000000000297 RDI: 0000000000000297
[   64.186237] RBP: ffff8801c8207a50 R08: 0000000000000000 R09: ffffed0039040ea7
[   64.189328] R10: 0000000000000001 R11: ffffed0039040ea6 R12: 0000000000000000
[   64.192634] R13: 0000000000000000 R14: ffff8801e2022800 R15: ffff8801d4ac2400
[   64.196105] FS:  00007f5c99b98700(0000) GS:ffff8801e5d00000(0000) knlGS:0000000000000000
[   64.199211] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   64.202046] CR2: 00000000000000b0 CR3: 00000001d1c48004 CR4: 00000000003606a0
[   64.205032] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   64.208221] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   64.211554] Call Trace:
[   64.213464]  ? rdma_disconnect+0xf0/0xf0
[   64.216124]  ? __radix_tree_replace+0xc3/0x110
[   64.219337]  ? node_tag_clear+0x81/0xb0
[   64.222140]  ? idr_alloc_u32+0x12e/0x1a0
[   64.224422]  ? __fprop_inc_percpu_max+0x150/0x150
[   64.226588]  ? tracing_record_taskinfo+0x10/0xc0
[   64.229763]  ? idr_alloc+0x76/0xc0
[   64.232186]  ? idr_alloc_u32+0x1a0/0x1a0
[   64.234505]  ? ucma_process_join+0x23d/0x460
[   64.237024]  ucma_process_join+0x23d/0x460
[   64.240076]  ? ucma_migrate_id+0x440/0x440
[   64.243284]  ? futex_wake+0x10b/0x2a0
[   64.245302]  ucma_join_multicast+0x88/0xe0
[   64.247783]  ? ucma_process_join+0x460/0x460
[   64.250841]  ? _copy_from_user+0x5e/0x90
[   64.253878]  ucma_write+0x174/0x1f0
[   64.257008]  ? ucma_resolve_route+0xf0/0xf0
[   64.259877]  ? rb_erase_cached+0x6c7/0x7f0
[   64.262746]  __vfs_write+0xc4/0x350
[   64.265537]  ? perf_syscall_enter+0xe4/0x5f0
[   64.267792]  ? kernel_read+0xa0/0xa0
[   64.270358]  ? perf_sched_cb_inc+0xc0/0xc0
[   64.272575]  ? syscall_exit_register+0x2a0/0x2a0
[   64.275367]  ? __switch_to+0x351/0x640
[   64.277700]  ? fsnotify+0x899/0x8f0
[   64.280530]  ? fsnotify_unmount_inodes+0x170/0x170
[   64.283156]  ? __fsnotify_update_child_dentry_flags+0x30/0x30
[   64.286182]  ? ring_buffer_record_is_on+0xd/0x20
[   64.288749]  ? __fget+0xa8/0xf0
[   64.291136]  vfs_write+0xf7/0x280
[   64.292972]  SyS_write+0xa1/0x120
[   64.294965]  ? SyS_read+0x120/0x120
[   64.297474]  ? SyS_read+0x120/0x120
[   64.299751]  do_syscall_64+0xeb/0x250
[   64.301826]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[   64.304352] RIP: 0033:0x7f5c994ade99
[   64.306711] RSP: 002b:00007f5c99b97d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   64.309577] RAX: ffffffffffffffda RBX: 00000000200001e4 RCX: 00007f5c994ade99
[   64.312334] RDX: 00000000000000a0 RSI: 00000000200001c0 RDI: 0000000000000015
[   64.315783] RBP: 00007f5c99b97ec0 R08: 0000000000000000 R09: 0000000000000000
[   64.318365] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5c99b97fc0
[   64.320980] R13: 0000000000000000 R14: 00007fff660e1c40 R15: 00007f5c99b989c0
[   64.323515] Code: e8 e8 79 08 ff 4c 89 ff 45 0f b6 a7 b8 01 00 00 e8 68 7c 08 ff 49 8b 1f 4d 89 e5 49 c1 e4 04 48 8
[   64.330753] RIP: rdma_join_multicast+0x26e/0x12c0 RSP: ffff8801c8207860
[   64.332979] CR2: 00000000000000b0
[   64.335550] ---[ end trace 0c00c17a408849c1 ]---

Reported-by: <[email protected]>
Fixes: c8f6a36 ("RDMA/cma: Add multicast communication support")
Signed-off-by: Leon Romanovsky <[email protected]>
Reviewed-by: Sean Hefty <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Users can provide garbage while calling to ucma_join_ip_multicast(),
it will indirectly cause to rdma_addr_size() return 0, making the
call to ucma_process_join(), which had the right checks, but it is
better to check the input as early as possible.

The following crash from syzkaller revealed it.

kernel BUG at lib/string.c:1052!
invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 4113 Comm: syz-executor0 Not tainted 4.16.0-rc5+ torvalds#261
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:fortify_panic+0x13/0x20 lib/string.c:1051
RSP: 0018:ffff8801ca81f8f0 EFLAGS: 00010286
RAX: 0000000000000022 RBX: 1ffff10039503f23 RCX: 0000000000000000
RDX: 0000000000000022 RSI: 1ffff10039503ed3 RDI: ffffed0039503f12
RBP: ffff8801ca81f8f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000006 R11: 0000000000000000 R12: ffff8801ca81f998
R13: ffff8801ca81f938 R14: ffff8801ca81fa58 R15: 000000000000fa00
FS:  0000000000000000(0000) GS:ffff8801db200000(0063) knlGS:000000000a12a900
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000008138024 CR3: 00000001cbb58004 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 memcpy include/linux/string.h:344 [inline]
 ucma_join_ip_multicast+0x36b/0x3b0 drivers/infiniband/core/ucma.c:1421
 ucma_write+0x2d6/0x3d0 drivers/infiniband/core/ucma.c:1633
 __vfs_write+0xef/0x970 fs/read_write.c:480
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 do_syscall_32_irqs_on arch/x86/entry/common.c:330 [inline]
 do_fast_syscall_32+0x3ec/0xf9f arch/x86/entry/common.c:392
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f9ec99
RSP: 002b:00000000ff8172cc EFLAGS: 00000282 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000100
RDX: 0000000000000063 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code: 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 48 89 df e8 42 2c e3 fb eb de
55 48 89 fe 48 c7 c7 80 75 98 86 48 89 e5 e8 85 95 94 fb <0f> 0b 90 90 90 90
90 90 90 90 90 90 90 55 48 89 e5 41 57 41 56
RIP: fortify_panic+0x13/0x20 lib/string.c:1051 RSP: ffff8801ca81f8f0

Fixes: 5bc2b7b ("RDMA/ucma: Allow user space to specify AF_IB when joining multicast")
Reported-by: <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Reviewed-by: Sean Hefty <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
On detaching of a disk which is a part of a RAID6 filesystem, the
following kernel OOPS may happen:

[63122.680461] BTRFS error (device sdo): bdev /dev/sdo errs: wr 0, rd 0, flush 1, corrupt 0, gen 0
[63122.719584] BTRFS warning (device sdo): lost page write due to IO error on /dev/sdo
[63122.719587] BTRFS error (device sdo): bdev /dev/sdo errs: wr 1, rd 0, flush 1, corrupt 0, gen 0
[63122.803516] BTRFS warning (device sdo): lost page write due to IO error on /dev/sdo
[63122.803519] BTRFS error (device sdo): bdev /dev/sdo errs: wr 2, rd 0, flush 1, corrupt 0, gen 0
[63122.863902] BTRFS critical (device sdo): fatal error on device /dev/sdo
[63122.935338] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
[63122.946554] IP: fail_bio_stripe+0x58/0xa0 [btrfs]
[63122.958185] PGD 9ecda067 P4D 9ecda067 PUD b2b37067 PMD 0
[63122.971202] Oops: 0000 [#1] SMP
[63123.006760] CPU: 0 PID: 3979 Comm: kworker/u8:9 Tainted: G W 4.14.2-16-scst34x+ torvalds#8
[63123.007091] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[63123.007402] Workqueue: btrfs-worker btrfs_worker_helper [btrfs]
[63123.007595] task: ffff880036ea4040 task.stack: ffffc90006384000
[63123.007796] RIP: 0010:fail_bio_stripe+0x58/0xa0 [btrfs]
[63123.007968] RSP: 0018:ffffc90006387ad8 EFLAGS: 00010287
[63123.008140] RAX: 0000000000000002 RBX: ffff88004beaa0b8 RCX: ffff8800b2bd5690
[63123.008359] RDX: 0000000000000000 RSI: ffff88007bb43500 RDI: ffff88004beaa000
[63123.008621] RBP: ffffc90006387ae8 R08: 0000000099100000 R09: ffff8800b2bd5600
[63123.008840] R10: 0000000000000004 R11: 0000000000010000 R12: ffff88007bb43500
[63123.009059] R13: 00000000fffffffb R14: ffff880036fc5180 R15: 0000000000000004
[63123.009278] FS: 0000000000000000(0000) GS:ffff8800b7000000(0000) knlGS:0000000000000000
[63123.009564] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[63123.009748] CR2: 0000000000000080 CR3: 00000000b0866000 CR4: 00000000000406f0
[63123.009969] Call Trace:
[63123.010085] raid_write_end_io+0x7e/0x80 [btrfs]
[63123.010251] bio_endio+0xa1/0x120
[63123.010378] generic_make_request+0x218/0x270
[63123.010921] submit_bio+0x66/0x130
[63123.011073] finish_rmw+0x3fc/0x5b0 [btrfs]
[63123.011245] full_stripe_write+0x96/0xc0 [btrfs]
[63123.011428] raid56_parity_write+0x117/0x170 [btrfs]
[63123.011604] btrfs_map_bio+0x2ec/0x320 [btrfs]
[63123.011759] ? ___cache_free+0x1c5/0x300
[63123.011909] __btrfs_submit_bio_done+0x26/0x50 [btrfs]
[63123.012087] run_one_async_done+0x9c/0xc0 [btrfs]
[63123.012257] normal_work_helper+0x19e/0x300 [btrfs]
[63123.012429] btrfs_worker_helper+0x12/0x20 [btrfs]
[63123.012656] process_one_work+0x14d/0x350
[63123.012888] worker_thread+0x4d/0x3a0
[63123.013026] ? _raw_spin_unlock_irqrestore+0x15/0x20
[63123.013192] kthread+0x109/0x140
[63123.013315] ? process_scheduled_works+0x40/0x40
[63123.013472] ? kthread_stop+0x110/0x110
[63123.013610] ret_from_fork+0x25/0x30
[63123.014469] RIP: fail_bio_stripe+0x58/0xa0 [btrfs] RSP: ffffc90006387ad8
[63123.014678] CR2: 0000000000000080
[63123.016590] ---[ end trace a295ea7259c17880 ]—

This is reproducible in a cycle, where a series of writes is followed by
SCSI device delete command. The test may take up to few minutes.

Fixes: 74d4699 ("block: replace bi_bdev with a gendisk pointer and partitions index")
[ no signed-off-by provided ]
Author: Dmitriy Gorokh <[email protected]>
Reviewed-by: Liu Bo <[email protected]>
Reviewed-by: David Sterba <[email protected]>
Signed-off-by: David Sterba <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
…specified

If set/unset mode of the tunnel_key action is not provided, ->init() still
returns 0, and the caller proceeds with bogus 'struct tc_action *' object,
this results in crash:

% tc actions add action tunnel_key src_ip 1.1.1.1 dst_ip 2.2.2.1 id 7 index 1

[   35.805515] general protection fault: 0000 [#1] SMP PTI
[   35.806161] Modules linked in: act_tunnel_key kvm_intel kvm irqbypass
crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64
crypto_simd glue_helper cryptd serio_raw
[   35.808233] CPU: 1 PID: 428 Comm: tc Not tainted 4.16.0-rc4+ torvalds#286
[   35.808929] RIP: 0010:tcf_action_init+0x90/0x190
[   35.809457] RSP: 0018:ffffb8edc068b9a0 EFLAGS: 00010206
[   35.810053] RAX: 1320c000000a0003 RBX: 0000000000000001 RCX: 0000000000000000
[   35.810866] RDX: 0000000000000070 RSI: 0000000000007965 RDI: ffffb8edc068b910
[   35.811660] RBP: ffffb8edc068b9d0 R08: 0000000000000000 R09: ffffb8edc068b808
[   35.812463] R10: ffffffffc02bf040 R11: 0000000000000040 R12: ffffb8edc068bb38
[   35.813235] R13: 0000000000000000 R14: 0000000000000000 R15: ffffb8edc068b910
[   35.814006] FS:  00007f3d0d8556c0(0000) GS:ffff91d1dbc40000(0000)
knlGS:0000000000000000
[   35.814881] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   35.815540] CR2: 000000000043f720 CR3: 0000000019248001 CR4: 00000000001606a0
[   35.816457] Call Trace:
[   35.817158]  tc_ctl_action+0x11a/0x220
[   35.817795]  rtnetlink_rcv_msg+0x23d/0x2e0
[   35.818457]  ? __slab_alloc+0x1c/0x30
[   35.819079]  ? __kmalloc_node_track_caller+0xb1/0x2b0
[   35.819544]  ? rtnl_calcit.isra.30+0xe0/0xe0
[   35.820231]  netlink_rcv_skb+0xce/0x100
[   35.820744]  netlink_unicast+0x164/0x220
[   35.821500]  netlink_sendmsg+0x293/0x370
[   35.822040]  sock_sendmsg+0x30/0x40
[   35.822508]  ___sys_sendmsg+0x2c5/0x2e0
[   35.823149]  ? pagecache_get_page+0x27/0x220
[   35.823714]  ? filemap_fault+0xa2/0x640
[   35.824423]  ? page_add_file_rmap+0x108/0x200
[   35.825065]  ? alloc_set_pte+0x2aa/0x530
[   35.825585]  ? finish_fault+0x4e/0x70
[   35.826140]  ? __handle_mm_fault+0xbc1/0x10d0
[   35.826723]  ? __sys_sendmsg+0x41/0x70
[   35.827230]  __sys_sendmsg+0x41/0x70
[   35.827710]  do_syscall_64+0x68/0x120
[   35.828195]  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
[   35.828859] RIP: 0033:0x7f3d0ca4da67
[   35.829331] RSP: 002b:00007ffc9f284338 EFLAGS: 00000246 ORIG_RAX:
000000000000002e
[   35.830304] RAX: ffffffffffffffda RBX: 00007ffc9f284460 RCX: 00007f3d0ca4da67
[   35.831247] RDX: 0000000000000000 RSI: 00007ffc9f2843b0 RDI: 0000000000000003
[   35.832167] RBP: 000000005aa6a7a9 R08: 0000000000000001 R09: 0000000000000000
[   35.833075] R10: 00000000000005f1 R11: 0000000000000246 R12: 0000000000000000
[   35.833997] R13: 00007ffc9f2884c0 R14: 0000000000000001 R15: 0000000000674640
[   35.834923] Code: 24 30 bb 01 00 00 00 45 31 f6 eb 5e 8b 50 08 83 c2 07 83 e2
fc 83 c2 70 49 8b 07 48 8b 40 70 48 85 c0 74 10 48 89 14 24 4c 89 ff <ff> d0 48
8b 14 24 48 01 c2 49 01 d6 45 85 ed 74 05 41 83 47 2c
[   35.837442] RIP: tcf_action_init+0x90/0x190 RSP: ffffb8edc068b9a0
[   35.838291] ---[ end trace a095c06ee4b97a26 ]---

Fixes: d0f6dd8 ("net/sched: Introduce act_tunnel_key")
Signed-off-by: Roman Mashak <[email protected]>
Acked-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Garbage supplied by user will cause to UCMA module provide zero
memory size for memcpy(), because it wasn't checked, it will
produce unpredictable results in rdma_resolve_addr().

[   42.873814] BUG: KASAN: null-ptr-deref in rdma_resolve_addr+0xc8/0xfb0
[   42.874816] Write of size 28 at addr 00000000000000a0 by task resaddr/1044
[   42.876765]
[   42.876960] CPU: 1 PID: 1044 Comm: resaddr Not tainted 4.16.0-rc1-00057-gaa56a5293d7e torvalds#34
[   42.877840] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
[   42.879691] Call Trace:
[   42.880236]  dump_stack+0x5c/0x77
[   42.880664]  kasan_report+0x163/0x380
[   42.881354]  ? rdma_resolve_addr+0xc8/0xfb0
[   42.881864]  memcpy+0x34/0x50
[   42.882692]  rdma_resolve_addr+0xc8/0xfb0
[   42.883366]  ? deref_stack_reg+0x88/0xd0
[   42.883856]  ? vsnprintf+0x31a/0x770
[   42.884686]  ? rdma_bind_addr+0xc40/0xc40
[   42.885327]  ? num_to_str+0x130/0x130
[   42.885773]  ? deref_stack_reg+0x88/0xd0
[   42.886217]  ? __read_once_size_nocheck.constprop.6+0x10/0x10
[   42.887698]  ? unwind_get_return_address_ptr+0x50/0x50
[   42.888302]  ? replace_slot+0x147/0x170
[   42.889176]  ? delete_node+0x12c/0x340
[   42.890223]  ? __radix_tree_lookup+0xa9/0x160
[   42.891196]  ? ucma_resolve_ip+0xb7/0x110
[   42.891917]  ucma_resolve_ip+0xb7/0x110
[   42.893003]  ? ucma_resolve_addr+0x190/0x190
[   42.893531]  ? _copy_from_user+0x5e/0x90
[   42.894204]  ucma_write+0x174/0x1f0
[   42.895162]  ? ucma_resolve_route+0xf0/0xf0
[   42.896309]  ? dequeue_task_fair+0x67e/0xd90
[   42.897192]  ? put_prev_entity+0x7d/0x170
[   42.897870]  ? ring_buffer_record_is_on+0xd/0x20
[   42.898439]  ? tracing_record_taskinfo_skip+0x20/0x50
[   42.899686]  __vfs_write+0xc4/0x350
[   42.900142]  ? kernel_read+0xa0/0xa0
[   42.900602]  ? firmware_map_remove+0xdf/0xdf
[   42.901135]  ? do_task_dead+0x5d/0x60
[   42.901598]  ? do_exit+0xcc6/0x1220
[   42.902789]  ? __fget+0xa8/0xf0
[   42.903190]  vfs_write+0xf7/0x280
[   42.903600]  SyS_write+0xa1/0x120
[   42.904206]  ? SyS_read+0x120/0x120
[   42.905710]  ? compat_start_thread+0x60/0x60
[   42.906423]  ? SyS_read+0x120/0x120
[   42.908716]  do_syscall_64+0xeb/0x250
[   42.910760]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[   42.912735] RIP: 0033:0x7f138b0afe99
[   42.914734] RSP: 002b:00007f138b799e98 EFLAGS: 00000287 ORIG_RAX: 0000000000000001
[   42.917134] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f138b0afe99
[   42.919487] RDX: 000000000000002e RSI: 0000000020000c40 RDI: 0000000000000004
[   42.922393] RBP: 00007f138b799ec0 R08: 00007f138b79a700 R09: 0000000000000000
[   42.925266] R10: 00007f138b79a700 R11: 0000000000000287 R12: 00007f138b799fc0
[   42.927570] R13: 0000000000000000 R14: 00007ffdbae757c0 R15: 00007f138b79a9c0
[   42.930047]
[   42.932681] Disabling lock debugging due to kernel taint
[   42.934795] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0
[   42.936939] IP: memcpy_erms+0x6/0x10
[   42.938864] PGD 80000001bea92067 P4D 80000001bea92067 PUD 1bea96067 PMD 0
[   42.941576] Oops: 0002 [#1] SMP KASAN PTI
[   42.943952] CPU: 1 PID: 1044 Comm: resaddr Tainted: G    B 4.16.0-rc1-00057-gaa56a5293d7e torvalds#34
[   42.946964] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
[   42.952336] RIP: 0010:memcpy_erms+0x6/0x10
[   42.954707] RSP: 0018:ffff8801c8b479c8 EFLAGS: 00010286
[   42.957227] RAX: 00000000000000a0 RBX: ffff8801c8b47ba0 RCX: 000000000000001c
[   42.960543] RDX: 000000000000001c RSI: ffff8801c8b47bbc RDI: 00000000000000a0
[   42.963867] RBP: ffff8801c8b47b60 R08: 0000000000000000 R09: ffffed0039168ed1
[   42.967303] R10: 0000000000000001 R11: ffffed0039168ed0 R12: ffff8801c8b47bbc
[   42.970685] R13: 00000000000000a0 R14: 1ffff10039168f4a R15: 0000000000000000
[   42.973631] FS:  00007f138b79a700(0000) GS:ffff8801e5d00000(0000) knlGS:0000000000000000
[   42.976831] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   42.979239] CR2: 00000000000000a0 CR3: 00000001be908002 CR4: 00000000003606a0
[   42.982060] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   42.984877] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   42.988033] Call Trace:
[   42.990487]  rdma_resolve_addr+0xc8/0xfb0
[   42.993202]  ? deref_stack_reg+0x88/0xd0
[   42.996055]  ? vsnprintf+0x31a/0x770
[   42.998707]  ? rdma_bind_addr+0xc40/0xc40
[   43.000985]  ? num_to_str+0x130/0x130
[   43.003410]  ? deref_stack_reg+0x88/0xd0
[   43.006302]  ? __read_once_size_nocheck.constprop.6+0x10/0x10
[   43.008780]  ? unwind_get_return_address_ptr+0x50/0x50
[   43.011178]  ? replace_slot+0x147/0x170
[   43.013517]  ? delete_node+0x12c/0x340
[   43.016019]  ? __radix_tree_lookup+0xa9/0x160
[   43.018755]  ? ucma_resolve_ip+0xb7/0x110
[   43.021270]  ucma_resolve_ip+0xb7/0x110
[   43.023968]  ? ucma_resolve_addr+0x190/0x190
[   43.026312]  ? _copy_from_user+0x5e/0x90
[   43.029384]  ucma_write+0x174/0x1f0
[   43.031861]  ? ucma_resolve_route+0xf0/0xf0
[   43.034782]  ? dequeue_task_fair+0x67e/0xd90
[   43.037483]  ? put_prev_entity+0x7d/0x170
[   43.040215]  ? ring_buffer_record_is_on+0xd/0x20
[   43.042990]  ? tracing_record_taskinfo_skip+0x20/0x50
[   43.045595]  __vfs_write+0xc4/0x350
[   43.048624]  ? kernel_read+0xa0/0xa0
[   43.051604]  ? firmware_map_remove+0xdf/0xdf
[   43.055379]  ? do_task_dead+0x5d/0x60
[   43.058000]  ? do_exit+0xcc6/0x1220
[   43.060783]  ? __fget+0xa8/0xf0
[   43.063133]  vfs_write+0xf7/0x280
[   43.065677]  SyS_write+0xa1/0x120
[   43.068647]  ? SyS_read+0x120/0x120
[   43.071179]  ? compat_start_thread+0x60/0x60
[   43.074025]  ? SyS_read+0x120/0x120
[   43.076705]  do_syscall_64+0xeb/0x250
[   43.079006]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[   43.081606] RIP: 0033:0x7f138b0afe99
[   43.083679] RSP: 002b:00007f138b799e98 EFLAGS: 00000287 ORIG_RAX: 0000000000000001
[   43.086802] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f138b0afe99
[   43.089989] RDX: 000000000000002e RSI: 0000000020000c40 RDI: 0000000000000004
[   43.092866] RBP: 00007f138b799ec0 R08: 00007f138b79a700 R09: 0000000000000000
[   43.096233] R10: 00007f138b79a700 R11: 0000000000000287 R12: 00007f138b799fc0
[   43.098913] R13: 0000000000000000 R14: 00007ffdbae757c0 R15: 00007f138b79a9c0
[   43.101809] Code: 90 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48
c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48
89 d1 <f3> a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38
[   43.107950] RIP: memcpy_erms+0x6/0x10 RSP: ffff8801c8b479c8

Reported-by: <[email protected]>
Fixes: 7521663 ("RDMA/cma: Export rdma cm interface to userspace")
Signed-off-by: Leon Romanovsky <[email protected]>
Reviewed-by: Sean Hefty <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Just when I had decided that flush_cache_range() was always called with
a valid context, Helge reported two cases where the
"BUG_ON(!vma->vm_mm->context);" was hit on the phantom buildd:

 kernel BUG at /mnt/sdb6/linux/linux-4.15.4/arch/parisc/kernel/cache.c:587!
 CPU: 1 PID: 3254 Comm: kworker/1:2 Tainted: G D 4.15.0-1-parisc64-smp #1 Debian 4.15.4-1+b1
 Workqueue: events free_ioctx
  IAOQ[0]: flush_cache_range+0x164/0x168
  IAOQ[1]: flush_cache_page+0x0/0x1c8
  RP(r2): unmap_page_range+0xae8/0xb88
 Backtrace:
  [<00000000404a6980>] unmap_page_range+0xae8/0xb88
  [<00000000404a6ae0>] unmap_single_vma+0xc0/0x188
  [<00000000404a6cdc>] zap_page_range_single+0x134/0x1f8
  [<00000000404a702c>] unmap_mapping_range+0x1cc/0x208
  [<0000000040461518>] truncate_pagecache+0x98/0x108
  [<0000000040461624>] truncate_setsize+0x9c/0xb8
  [<00000000405d7f30>] put_aio_ring_file+0x80/0x100
  [<00000000405d803c>] aio_free_ring+0x8c/0x290
  [<00000000405d82c0>] free_ioctx+0x80/0x180
  [<0000000040284e6c>] process_one_work+0x21c/0x668
  [<00000000402854c4>] worker_thread+0x20c/0x778
  [<0000000040291d44>] kthread+0x2d4/0x2e0
  [<0000000040204020>] end_fault_vector+0x20/0xc0

This indicates that we need to handle the no context case in
flush_cache_range() as we do in flush_cache_mm().

In thinking about this, I realized that we don't need to flush the TLB
when there is no context.  So, I added context checks to the large flush
cases in flush_cache_mm() and flush_cache_range().  The large flush case
occurs frequently in flush_cache_mm() and the change should improve fork
performance.

The v2 version of this change removes the BUG_ON from flush_cache_page()
by skipping the TLB flush when there is no context.  I also added code
to flush the TLB in flush_cache_mm() and flush_cache_range() when we
have a context that's not current.  Now all three routines handle TLB
flushes in a similar manner.

Signed-off-by: John David Anglin <[email protected]>
Cc: [email protected] # 4.9+
Signed-off-by: Helge Deller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
when the following command

 # tc actions replace action vlan pop index 100

is run for the first time, and tcf_vlan_init() fails allocating struct
tcf_vlan_params, tcf_vlan_cleanup() calls kfree_rcu(NULL, ...). This causes
the following error:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
 IP: __call_rcu+0x23/0x2b0
 PGD 80000000760a2067 P4D 80000000760a2067 PUD 742c1067 PMD 0
 Oops: 0002 [#1] SMP PTI
 Modules linked in: act_vlan(E) ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 snd_hda_codec_generic snd_hda_intel mbcache snd_hda_codec jbd2 snd_hda_core crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc snd_hwdep snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd snd_timer glue_helper snd cryptd joydev soundcore virtio_balloon pcspkr i2c_piix4 nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm virtio_console virtio_blk virtio_net ata_piix crc32c_intel libata virtio_pci i2c_core virtio_ring serio_raw virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: act_vlan]
 CPU: 3 PID: 3119 Comm: tc Tainted: G            E    4.16.0-rc4.act_vlan.orig+ torvalds#403
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:__call_rcu+0x23/0x2b0
 RSP: 0018:ffffaac3005fb798 EFLAGS: 00010246
 RAX: ffffffffc0704080 RBX: ffff97f2b4bbe900 RCX: 00000000ffffffff
 RDX: ffffffffabca5f00 RSI: 0000000000000010 RDI: 0000000000000010
 RBP: 0000000000000010 R08: 0000000000000001 R09: 0000000000000044
 R10: 00000000fd003000 R11: ffff97f2faab5b91 R12: 0000000000000000
 R13: ffffffffabca5f00 R14: ffff97f2fb80202c R15: 00000000fffffff4
 FS:  00007f68f75b4740(0000) GS:ffff97f2ffd80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000018 CR3: 0000000072b52001 CR4: 00000000001606e0
 Call Trace:
  __tcf_idr_release+0x79/0xf0
  tcf_vlan_init+0x168/0x270 [act_vlan]
  tcf_action_init_1+0x2cc/0x430
  tcf_action_init+0xd3/0x1b0
  tc_ctl_action+0x18b/0x240
  rtnetlink_rcv_msg+0x29c/0x310
  ? _cond_resched+0x15/0x30
  ? __kmalloc_node_track_caller+0x1b9/0x270
  ? rtnl_calcit.isra.28+0x100/0x100
  netlink_rcv_skb+0xd2/0x110
  netlink_unicast+0x17c/0x230
  netlink_sendmsg+0x2cd/0x3c0
  sock_sendmsg+0x30/0x40
  ___sys_sendmsg+0x27a/0x290
  ? filemap_map_pages+0x34a/0x3a0
  ? __handle_mm_fault+0xbfd/0xe20
  __sys_sendmsg+0x51/0x90
  do_syscall_64+0x6e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 RIP: 0033:0x7f68f69c5ba0
 RSP: 002b:00007fffd79c1118 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007fffd79c1240 RCX: 00007f68f69c5ba0
 RDX: 0000000000000000 RSI: 00007fffd79c1190 RDI: 0000000000000003
 RBP: 000000005aaa708e R08: 0000000000000002 R09: 0000000000000000
 R10: 00007fffd79c0ba0 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007fffd79c1254 R14: 0000000000000001 R15: 0000000000669f60
 Code: 5d e9 42 da ff ff 66 90 0f 1f 44 00 00 41 57 41 56 41 55 49 89 d5 41 54 55 48 89 fd 53 48 83 ec 08 40 f6 c7 07 0f 85 19 02 00 00 <48> 89 75 08 48 c7 45 00 00 00 00 00 9c 58 0f 1f 44 00 00 49 89
 RIP: __call_rcu+0x23/0x2b0 RSP: ffffaac3005fb798
 CR2: 0000000000000018

fix this in tcf_vlan_cleanup(), ensuring that kfree_rcu(p, ...) is called
only when p is not NULL.

Fixes: 4c5b9d9 ("act_vlan: VLAN action rewrite to use RCU lock/unlock and update")
Acked-by: Jiri Pirko <[email protected]>
Acked-by: Manish Kurup <[email protected]>
Signed-off-by: Davide Caratti <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
when the following command

 # tc action add action csum udp continue index 100

is run for the first time, and tcf_csum_init() fails allocating struct
tcf_csum, tcf_csum_cleanup() calls kfree_rcu(NULL,...). This causes the
following error:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
 IP: __call_rcu+0x23/0x2b0
 PGD 80000000740b4067 P4D 80000000740b4067 PUD 32e7f067 PMD 0
 Oops: 0002 [#1] SMP PTI
 Modules linked in: act_csum(E) act_vlan ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache jbd2 crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_codec_generic pcbc snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer aesni_intel crypto_simd glue_helper cryptd snd joydev pcspkr virtio_balloon i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm virtio_blk drm virtio_net virtio_console ata_piix crc32c_intel libata virtio_pci serio_raw i2c_core virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: act_vlan]
 CPU: 2 PID: 5763 Comm: tc Tainted: G            E    4.16.0-rc4.act_vlan.orig+ torvalds#403
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:__call_rcu+0x23/0x2b0
 RSP: 0018:ffffb275803e77c0 EFLAGS: 00010246
 RAX: ffffffffc057b080 RBX: ffff9674bc6f5240 RCX: 00000000ffffffff
 RDX: ffffffff928a5f00 RSI: 0000000000000008 RDI: 0000000000000008
 RBP: 0000000000000008 R08: 0000000000000001 R09: 0000000000000044
 R10: 0000000000000220 R11: ffff9674b9ab4821 R12: 0000000000000000
 R13: ffffffff928a5f00 R14: 0000000000000000 R15: 0000000000000001
 FS:  00007fa6368d8740(0000) GS:ffff9674bfd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000010 CR3: 0000000073dec001 CR4: 00000000001606e0
 Call Trace:
  __tcf_idr_release+0x79/0xf0
  tcf_csum_init+0xfb/0x180 [act_csum]
  tcf_action_init_1+0x2cc/0x430
  tcf_action_init+0xd3/0x1b0
  tc_ctl_action+0x18b/0x240
  rtnetlink_rcv_msg+0x29c/0x310
  ? _cond_resched+0x15/0x30
  ? __kmalloc_node_track_caller+0x1b9/0x270
  ? rtnl_calcit.isra.28+0x100/0x100
  netlink_rcv_skb+0xd2/0x110
  netlink_unicast+0x17c/0x230
  netlink_sendmsg+0x2cd/0x3c0
  sock_sendmsg+0x30/0x40
  ___sys_sendmsg+0x27a/0x290
  ? filemap_map_pages+0x34a/0x3a0
  ? __handle_mm_fault+0xbfd/0xe20
  __sys_sendmsg+0x51/0x90
  do_syscall_64+0x6e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 RIP: 0033:0x7fa635ce9ba0
 RSP: 002b:00007ffc185b0fc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007ffc185b10f0 RCX: 00007fa635ce9ba0
 RDX: 0000000000000000 RSI: 00007ffc185b1040 RDI: 0000000000000003
 RBP: 000000005aaa85e0 R08: 0000000000000002 R09: 0000000000000000
 R10: 00007ffc185b0a20 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007ffc185b1104 R14: 0000000000000001 R15: 0000000000669f60
 Code: 5d e9 42 da ff ff 66 90 0f 1f 44 00 00 41 57 41 56 41 55 49 89 d5 41 54 55 48 89 fd 53 48 83 ec 08 40 f6 c7 07 0f 85 19 02 00 00 <48> 89 75 08 48 c7 45 00 00 00 00 00 9c 58 0f 1f 44 00 00 49 89
 RIP: __call_rcu+0x23/0x2b0 RSP: ffffb275803e77c0
 CR2: 0000000000000010

fix this in tcf_csum_cleanup(), ensuring that kfree_rcu(param, ...) is
called only when param is not NULL.

Fixes: 9c5f69b ("net/sched: act_csum: don't use spinlock in the fast path")
Signed-off-by: Davide Caratti <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
when the following command

 # tc action add action tunnel_key unset index 100

is run for the first time, and tunnel_key_init() fails to allocate struct
tcf_tunnel_key_params, tunnel_key_release() dereferences NULL pointers.
This causes the following error:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
 IP: tunnel_key_release+0xd/0x40 [act_tunnel_key]
 PGD 8000000033787067 P4D 8000000033787067 PUD 74646067 PMD 0
 Oops: 0000 [#1] SMP PTI
 Modules linked in: act_tunnel_key(E) act_csum ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 mbcache jbd2 crct10dif_pclmul crc32_pclmul snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel pcbc snd_hda_codec snd_hda_core snd_hwdep snd_seq aesni_intel snd_seq_device crypto_simd glue_helper snd_pcm cryptd joydev snd_timer pcspkr virtio_balloon snd i2c_piix4 soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm virtio_net virtio_blk drm virtio_console crc32c_intel ata_piix serio_raw i2c_core virtio_pci libata virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod
 CPU: 2 PID: 3101 Comm: tc Tainted: G            E    4.16.0-rc4.act_vlan.orig+ torvalds#403
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:tunnel_key_release+0xd/0x40 [act_tunnel_key]
 RSP: 0018:ffffba46803b7768 EFLAGS: 00010286
 RAX: ffffffffc09010a0 RBX: 0000000000000000 RCX: 0000000000000024
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff99ee336d7480
 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044
 R10: 0000000000000220 R11: ffff99ee79d73131 R12: 0000000000000000
 R13: ffff99ee32d67610 R14: ffff99ee7671dc38 R15: 00000000fffffff4
 FS:  00007febcb2cd740(0000) GS:ffff99ee7fd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000010 CR3: 000000007c8e4005 CR4: 00000000001606e0
 Call Trace:
  __tcf_idr_release+0x79/0xf0
  tunnel_key_init+0xd9/0x460 [act_tunnel_key]
  tcf_action_init_1+0x2cc/0x430
  tcf_action_init+0xd3/0x1b0
  tc_ctl_action+0x18b/0x240
  rtnetlink_rcv_msg+0x29c/0x310
  ? _cond_resched+0x15/0x30
  ? __kmalloc_node_track_caller+0x1b9/0x270
  ? rtnl_calcit.isra.28+0x100/0x100
  netlink_rcv_skb+0xd2/0x110
  netlink_unicast+0x17c/0x230
  netlink_sendmsg+0x2cd/0x3c0
  sock_sendmsg+0x30/0x40
  ___sys_sendmsg+0x27a/0x290
  __sys_sendmsg+0x51/0x90
  do_syscall_64+0x6e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 RIP: 0033:0x7febca6deba0
 RSP: 002b:00007ffe7b0dd128 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007ffe7b0dd250 RCX: 00007febca6deba0
 RDX: 0000000000000000 RSI: 00007ffe7b0dd1a0 RDI: 0000000000000003
 RBP: 000000005aaa90cb R08: 0000000000000002 R09: 0000000000000000
 R10: 00007ffe7b0dcba0 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007ffe7b0dd264 R14: 0000000000000001 R15: 0000000000669f60
 Code: 44 00 00 8b 0d b5 23 00 00 48 8b 87 48 10 00 00 48 8b 3c c8 e9 a5 e5 d8 c3 0f 1f 44 00 00 0f 1f 44 00 00 53 48 8b 9f b0 00 00 00 <83> 7b 10 01 74 0b 48 89 df 31 f6 5b e9 f2 fa 7f c3 48 8b 7b 18
 RIP: tunnel_key_release+0xd/0x40 [act_tunnel_key] RSP: ffffba46803b7768
 CR2: 0000000000000010

Fix this in tunnel_key_release(), ensuring 'param' is not NULL before
dereferencing it.

Fixes: d0f6dd8 ("net/sched: Introduce act_tunnel_key")
Signed-off-by: Davide Caratti <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
when the following command

 # tc action add action sample rate 100 group 100 index 100

is run for the first time, and psample_group_get(100) fails to create a
new group, tcf_sample_cleanup() calls psample_group_put(NULL), thus
causing the following error:

 BUG: unable to handle kernel NULL pointer dereference at 000000000000001c
 IP: psample_group_put+0x15/0x71 [psample]
 PGD 8000000075775067 P4D 8000000075775067 PUD 7453c067 PMD 0
 Oops: 0002 [#1] SMP PTI
 Modules linked in: act_sample(E) psample ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core mbcache jbd2 crct10dif_pclmul snd_hwdep crc32_pclmul snd_seq ghash_clmulni_intel pcbc snd_seq_device snd_pcm aesni_intel crypto_simd snd_timer glue_helper snd cryptd joydev pcspkr i2c_piix4 soundcore virtio_balloon nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm virtio_net ata_piix virtio_console virtio_blk libata serio_raw crc32c_intel virtio_pci i2c_core virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: act_tunnel_key]
 CPU: 2 PID: 5740 Comm: tc Tainted: G            E    4.16.0-rc4.act_vlan.orig+ torvalds#403
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:psample_group_put+0x15/0x71 [psample]
 RSP: 0018:ffffb8a80032f7d0 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000024
 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffffffc06d93c0
 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000044
 R10: 00000000bd003000 R11: ffff979fba04aa59 R12: 0000000000000000
 R13: 0000000000000000 R14: 0000000000000000 R15: ffff979fbba3f22c
 FS:  00007f7638112740(0000) GS:ffff979fbfd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000000000000001c CR3: 00000000734ea001 CR4: 00000000001606e0
 Call Trace:
  __tcf_idr_release+0x79/0xf0
  tcf_sample_init+0x125/0x1d0 [act_sample]
  tcf_action_init_1+0x2cc/0x430
  tcf_action_init+0xd3/0x1b0
  tc_ctl_action+0x18b/0x240
  rtnetlink_rcv_msg+0x29c/0x310
  ? _cond_resched+0x15/0x30
  ? __kmalloc_node_track_caller+0x1b9/0x270
  ? rtnl_calcit.isra.28+0x100/0x100
  netlink_rcv_skb+0xd2/0x110
  netlink_unicast+0x17c/0x230
  netlink_sendmsg+0x2cd/0x3c0
  sock_sendmsg+0x30/0x40
  ___sys_sendmsg+0x27a/0x290
  ? filemap_map_pages+0x34a/0x3a0
  ? __handle_mm_fault+0xbfd/0xe20
  __sys_sendmsg+0x51/0x90
  do_syscall_64+0x6e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 RIP: 0033:0x7f7637523ba0
 RSP: 002b:00007fff0473ef58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007fff0473f080 RCX: 00007f7637523ba0
 RDX: 0000000000000000 RSI: 00007fff0473efd0 RDI: 0000000000000003
 RBP: 000000005aaaac80 R08: 0000000000000002 R09: 0000000000000000
 R10: 00007fff0473e9e0 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007fff0473f094 R14: 0000000000000001 R15: 0000000000669f60
 Code: be 02 00 00 00 48 89 df e8 a9 fe ff ff e9 7c ff ff ff 0f 1f 40 00 0f 1f 44 00 00 53 48 89 fb 48 c7 c7 c0 93 6d c0 e8 db 20 8c ef <83> 6b 1c 01 74 10 48 c7 c7 c0 93 6d c0 ff 14 25 e8 83 83 b0 5b
 RIP: psample_group_put+0x15/0x71 [psample] RSP: ffffb8a80032f7d0
 CR2: 000000000000001c

Fix it in tcf_sample_cleanup(), ensuring that calls to psample_group_put(p)
are done only when p is not NULL.

Fixes: cadb9c9 ("net/sched: act_sample: Fix error path in init")
Signed-off-by: Davide Caratti <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
when the following command

 # tc action replace action skbmod swap mac index 100

is run for the first time, and tcf_skbmod_init() fails to allocate struct
tcf_skbmod_params, tcf_skbmod_cleanup() calls kfree_rcu(NULL), thus
causing the following error:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
 IP: __call_rcu+0x23/0x2b0
 PGD 8000000034057067 P4D 8000000034057067 PUD 74937067 PMD 0
 Oops: 0002 [#1] SMP PTI
 Modules linked in: act_skbmod(E) psample ip6table_filter ip6_tables iptable_filter binfmt_misc ext4 snd_hda_codec_generic snd_hda_intel snd_hda_codec crct10dif_pclmul mbcache jbd2 crc32_pclmul snd_hda_core ghash_clmulni_intel snd_hwdep pcbc snd_seq snd_seq_device snd_pcm aesni_intel snd_timer crypto_simd glue_helper snd cryptd virtio_balloon joydev soundcore pcspkr i2c_piix4 nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm virtio_console virtio_net virtio_blk ata_piix libata crc32c_intel virtio_pci serio_raw virtio_ring virtio i2c_core floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: act_skbmod]
 CPU: 3 PID: 3144 Comm: tc Tainted: G            E    4.16.0-rc4.act_vlan.orig+ torvalds#403
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
 RIP: 0010:__call_rcu+0x23/0x2b0
 RSP: 0018:ffffbd2e403e7798 EFLAGS: 00010246
 RAX: ffffffffc0872080 RBX: ffff981d34bff780 RCX: 00000000ffffffff
 RDX: ffffffff922a5f00 RSI: 0000000000000000 RDI: 0000000000000000
 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000000021f
 R10: 000000003d003000 R11: 0000000000aaaaaa R12: 0000000000000000
 R13: ffffffff922a5f00 R14: 0000000000000001 R15: ffff981d3b698c2c
 FS:  00007f3678292740(0000) GS:ffff981d3fd80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000008 CR3: 000000007c57a006 CR4: 00000000001606e0
 Call Trace:
  __tcf_idr_release+0x79/0xf0
  tcf_skbmod_init+0x1d1/0x210 [act_skbmod]
  tcf_action_init_1+0x2cc/0x430
  tcf_action_init+0xd3/0x1b0
  tc_ctl_action+0x18b/0x240
  rtnetlink_rcv_msg+0x29c/0x310
  ? _cond_resched+0x15/0x30
  ? __kmalloc_node_track_caller+0x1b9/0x270
  ? rtnl_calcit.isra.28+0x100/0x100
  netlink_rcv_skb+0xd2/0x110
  netlink_unicast+0x17c/0x230
  netlink_sendmsg+0x2cd/0x3c0
  sock_sendmsg+0x30/0x40
  ___sys_sendmsg+0x27a/0x290
  ? filemap_map_pages+0x34a/0x3a0
  ? __handle_mm_fault+0xbfd/0xe20
  __sys_sendmsg+0x51/0x90
  do_syscall_64+0x6e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
 RIP: 0033:0x7f36776a3ba0
 RSP: 002b:00007fff4703b618 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 00007fff4703b740 RCX: 00007f36776a3ba0
 RDX: 0000000000000000 RSI: 00007fff4703b690 RDI: 0000000000000003
 RBP: 000000005aaaba36 R08: 0000000000000002 R09: 0000000000000000
 R10: 00007fff4703b0a0 R11: 0000000000000246 R12: 0000000000000000
 R13: 00007fff4703b754 R14: 0000000000000001 R15: 0000000000669f60
 Code: 5d e9 42 da ff ff 66 90 0f 1f 44 00 00 41 57 41 56 41 55 49 89 d5 41 54 55 48 89 fd 53 48 83 ec 08 40 f6 c7 07 0f 85 19 02 00 00 <48> 89 75 08 48 c7 45 00 00 00 00 00 9c 58 0f 1f 44 00 00 49 89
 RIP: __call_rcu+0x23/0x2b0 RSP: ffffbd2e403e7798
 CR2: 0000000000000008

Fix it in tcf_skbmod_cleanup(), ensuring that kfree_rcu(p, ...) is called
only when p is not NULL.

Fixes: 86da71b ("net_sched: Introduce skbmod action")
Signed-off-by: Davide Caratti <[email protected]>
Acked-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Prior to access UCMA commands, the context should be initialized
and connected to CM_ID with ucma_create_id(). In case user skips
this step, he can provide non-valid ctx without CM_ID and cause
to multiple NULL dereferences.

Also there are situations where the create_id can be raced with
other user access, ensure that the context is only shared to
other threads once it is fully initialized to avoid the races.

[  109.088108] BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
[  109.090315] IP: ucma_connect+0x138/0x1d0
[  109.092595] PGD 80000001dc02d067 P4D 80000001dc02d067 PUD 1da9ef067 PMD 0
[  109.095384] Oops: 0000 [#1] SMP KASAN PTI
[  109.097834] CPU: 0 PID: 663 Comm: uclose Tainted: G    B 4.16.0-rc1-00062-g2975d5de6428 torvalds#45
[  109.100816] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014
[  109.105943] RIP: 0010:ucma_connect+0x138/0x1d0
[  109.108850] RSP: 0018:ffff8801c8567a80 EFLAGS: 00010246
[  109.111484] RAX: 0000000000000000 RBX: 1ffff100390acf50 RCX: ffffffff9d7812e2
[  109.114496] RDX: 1ffffffff3f507a5 RSI: 0000000000000297 RDI: 0000000000000297
[  109.117490] RBP: ffff8801daa15600 R08: 0000000000000000 R09: ffffed00390aceeb
[  109.120429] R10: 0000000000000001 R11: ffffed00390aceea R12: 0000000000000000
[  109.123318] R13: 0000000000000120 R14: ffff8801de6459c0 R15: 0000000000000118
[  109.126221] FS:  00007fabb68d6700(0000) GS:ffff8801e5c00000(0000) knlGS:0000000000000000
[  109.129468] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  109.132523] CR2: 0000000000000020 CR3: 00000001d45d8003 CR4: 00000000003606b0
[  109.135573] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  109.138716] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  109.142057] Call Trace:
[  109.144160]  ? ucma_listen+0x110/0x110
[  109.146386]  ? wake_up_q+0x59/0x90
[  109.148853]  ? futex_wake+0x10b/0x2a0
[  109.151297]  ? save_stack+0x89/0xb0
[  109.153489]  ? _copy_from_user+0x5e/0x90
[  109.155500]  ucma_write+0x174/0x1f0
[  109.157933]  ? ucma_resolve_route+0xf0/0xf0
[  109.160389]  ? __mod_node_page_state+0x1d/0x80
[  109.162706]  __vfs_write+0xc4/0x350
[  109.164911]  ? kernel_read+0xa0/0xa0
[  109.167121]  ? path_openat+0x1b10/0x1b10
[  109.169355]  ? fsnotify+0x899/0x8f0
[  109.171567]  ? fsnotify_unmount_inodes+0x170/0x170
[  109.174145]  ? __fget+0xa8/0xf0
[  109.177110]  vfs_write+0xf7/0x280
[  109.179532]  SyS_write+0xa1/0x120
[  109.181885]  ? SyS_read+0x120/0x120
[  109.184482]  ? compat_start_thread+0x60/0x60
[  109.187124]  ? SyS_read+0x120/0x120
[  109.189548]  do_syscall_64+0xeb/0x250
[  109.192178]  entry_SYSCALL_64_after_hwframe+0x21/0x86
[  109.194725] RIP: 0033:0x7fabb61ebe99
[  109.197040] RSP: 002b:00007fabb68d5e98 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[  109.200294] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fabb61ebe99
[  109.203399] RDX: 0000000000000120 RSI: 00000000200001c0 RDI: 0000000000000004
[  109.206548] RBP: 00007fabb68d5ec0 R08: 0000000000000000 R09: 0000000000000000
[  109.209902] R10: 0000000000000000 R11: 0000000000000202 R12: 00007fabb68d5fc0
[  109.213327] R13: 0000000000000000 R14: 00007fff40ab2430 R15: 00007fabb68d69c0
[  109.216613] Code: 88 44 24 2c 0f b6 84 24 6e 01 00 00 88 44 24 2d 0f
b6 84 24 69 01 00 00 88 44 24 2e 8b 44 24 60 89 44 24 30 e8 da f6 06 ff
31 c0 <66> 41 83 7c 24 20 1b 75 04 8b 44 24 64 48 8d 74 24 20 4c 89 e7
[  109.223602] RIP: ucma_connect+0x138/0x1d0 RSP: ffff8801c8567a80
[  109.226256] CR2: 0000000000000020

Fixes: 7521663 ("RDMA/cma: Export rdma cm interface to userspace")
Reported-by: <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Prasad reported that he has seen crashes in BPF subsystem with netd
on Android with arm64 in the form of (note, the taint is unrelated):

  [ 4134.721483] Unable to handle kernel paging request at virtual address 800000001
  [ 4134.820925] Mem abort info:
  [ 4134.901283]   Exception class = DABT (current EL), IL = 32 bits
  [ 4135.016736]   SET = 0, FnV = 0
  [ 4135.119820]   EA = 0, S1PTW = 0
  [ 4135.201431] Data abort info:
  [ 4135.301388]   ISV = 0, ISS = 0x00000021
  [ 4135.359599]   CM = 0, WnR = 0
  [ 4135.470873] user pgtable: 4k pages, 39-bit VAs, pgd = ffffffe39b946000
  [ 4135.499757] [0000000800000001] *pgd=0000000000000000, *pud=0000000000000000
  [ 4135.660725] Internal error: Oops: 96000021 [#1] PREEMPT SMP
  [ 4135.674610] Modules linked in:
  [ 4135.682883] CPU: 5 PID: 1260 Comm: netd Tainted: G S      W       4.14.19+ #1
  [ 4135.716188] task: ffffffe39f4aa380 task.stack: ffffff801d4e0000
  [ 4135.731599] PC is at bpf_prog_add+0x20/0x68
  [ 4135.741746] LR is at bpf_prog_inc+0x20/0x2c
  [ 4135.751788] pc : [<ffffff94ab7ad584>] lr : [<ffffff94ab7ad638>] pstate: 60400145
  [ 4135.769062] sp : ffffff801d4e3ce0
  [...]
  [ 4136.258315] Process netd (pid: 1260, stack limit = 0xffffff801d4e0000)
  [ 4136.273746] Call trace:
  [...]
  [ 4136.442494] 3ca0: ffffff94ab7ad584 0000000060400145 ffffffe3a01bf8f8 0000000000000006
  [ 4136.460936] 3cc0: 0000008000000000 ffffff94ab844204 ffffff801d4e3cf0 ffffff94ab7ad584
  [ 4136.479241] [<ffffff94ab7ad584>] bpf_prog_add+0x20/0x68
  [ 4136.491767] [<ffffff94ab7ad638>] bpf_prog_inc+0x20/0x2c
  [ 4136.504536] [<ffffff94ab7b5d08>] bpf_obj_get_user+0x204/0x22c
  [ 4136.518746] [<ffffff94ab7ade68>] SyS_bpf+0x5a8/0x1a88

Android's netd was basically pinning the uid cookie BPF map in BPF
fs (/sys/fs/bpf/traffic_cookie_uid_map) and later on retrieving it
again resulting in above panic. Issue is that the map was wrongly
identified as a prog! Above kernel was compiled with clang 4.0,
and it turns out that clang decided to merge the bpf_prog_iops and
bpf_map_iops into a single memory location, such that the two i_ops
could then not be distinguished anymore.

Reason for this miscompilation is that clang has the more aggressive
-fmerge-all-constants enabled by default. In fact, clang source code
has a comment about it in lib/AST/ExprConstant.cpp on why it is okay
to do so:

  Pointers with different bases cannot represent the same object.
  (Note that clang defaults to -fmerge-all-constants, which can
  lead to inconsistent results for comparisons involving the address
  of a constant; this generally doesn't matter in practice.)

The issue never appeared with gcc however, since gcc does not enable
-fmerge-all-constants by default and even *explicitly* states in
it's option description that using this flag results in non-conforming
behavior, quote from man gcc:

  Languages like C or C++ require each variable, including multiple
  instances of the same variable in recursive calls, to have distinct
  locations, so using this option results in non-conforming behavior.

There are also various clang bug reports open on that matter [1],
where clang developers acknowledge the non-conforming behavior,
and refer to disabling it with -fno-merge-all-constants. But even
if this gets fixed in clang today, there are already users out there
that triggered this. Thus, fix this issue by explicitly adding
-fno-merge-all-constants to the kernel's Makefile to generically
disable this optimization, since potentially other places in the
kernel could subtly break as well.

Note, there is also a flag called -fmerge-constants (not supported
by clang), which is more conservative and only applies to strings
and it's enabled in gcc's -O/-O2/-O3/-Os optimization levels. In
gcc's code, the two flags -fmerge-{all-,}constants share the same
variable internally, so when disabling it via -fno-merge-all-constants,
then we really don't merge any const data (e.g. strings), and text
size increases with gcc (14,927,214 -> 14,942,646 for vmlinux.o).

  $ gcc -fverbose-asm -O2 foo.c -S -o foo.S
    -> foo.S lists -fmerge-constants under options enabled
  $ gcc -fverbose-asm -O2 -fno-merge-all-constants foo.c -S -o foo.S
    -> foo.S doesn't list -fmerge-constants under options enabled
  $ gcc -fverbose-asm -O2 -fno-merge-all-constants -fmerge-constants foo.c -S -o foo.S
    -> foo.S lists -fmerge-constants under options enabled

Thus, as a workaround we need to set both -fno-merge-all-constants
*and* -fmerge-constants in the Makefile in order for text size to
stay as is.

  [1] https://bugs.llvm.org/show_bug.cgi?id=18538

Reported-by: Prasad Sodagudi <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Chenbo Feng <[email protected]>
Cc: Richard Smith <[email protected]>
Cc: Chandler Carruth <[email protected]>
Cc: [email protected]
Tested-by: Prasad Sodagudi <[email protected]>
Acked-by: Alexei Starovoitov <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
The seg6_build_state() function is called with RCU read lock held,
so we cannot use GFP_KERNEL. This patch uses GFP_ATOMIC instead.

[   92.770271] =============================
[   92.770628] WARNING: suspicious RCU usage
[   92.770921] 4.16.0-rc4+ torvalds#12 Not tainted
[   92.771277] -----------------------------
[   92.771585] ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section!
[   92.772279]
[   92.772279] other info that might help us debug this:
[   92.772279]
[   92.773067]
[   92.773067] rcu_scheduler_active = 2, debug_locks = 1
[   92.773514] 2 locks held by ip/2413:
[   92.773765]  #0:  (rtnl_mutex){+.+.}, at: [<00000000e5461720>] rtnetlink_rcv_msg+0x441/0x4d0
[   92.774377]  #1:  (rcu_read_lock){....}, at: [<00000000df4f161e>] lwtunnel_build_state+0x59/0x210
[   92.775065]
[   92.775065] stack backtrace:
[   92.775371] CPU: 0 PID: 2413 Comm: ip Not tainted 4.16.0-rc4+ torvalds#12
[   92.775791] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1.fc27 04/01/2014
[   92.776608] Call Trace:
[   92.776852]  dump_stack+0x7d/0xbc
[   92.777130]  __schedule+0x133/0xf00
[   92.777393]  ? unwind_get_return_address_ptr+0x50/0x50
[   92.777783]  ? __sched_text_start+0x8/0x8
[   92.778073]  ? rcu_is_watching+0x19/0x30
[   92.778383]  ? kernel_text_address+0x49/0x60
[   92.778800]  ? __kernel_text_address+0x9/0x30
[   92.779241]  ? unwind_get_return_address+0x29/0x40
[   92.779727]  ? pcpu_alloc+0x102/0x8f0
[   92.780101]  _cond_resched+0x23/0x50
[   92.780459]  __mutex_lock+0xbd/0xad0
[   92.780818]  ? pcpu_alloc+0x102/0x8f0
[   92.781194]  ? seg6_build_state+0x11d/0x240
[   92.781611]  ? save_stack+0x9b/0xb0
[   92.781965]  ? __ww_mutex_wakeup_for_backoff+0xf0/0xf0
[   92.782480]  ? seg6_build_state+0x11d/0x240
[   92.782925]  ? lwtunnel_build_state+0x1bd/0x210
[   92.783393]  ? ip6_route_info_create+0x687/0x1640
[   92.783846]  ? ip6_route_add+0x74/0x110
[   92.784236]  ? inet6_rtm_newroute+0x8a/0xd0

Fixes: 6c8702c ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: David Lebrun <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
When using seg6 in encap mode, we call ipv6_dev_get_saddr() to set the
source address of the outer IPv6 header, in case none was specified.
Using skb->dev can lead to BUG() when it is in an inconsistent state.
This patch uses the net_device attached to the skb's dst instead.

[940807.667429] BUG: unable to handle kernel NULL pointer dereference at 000000000000047c
[940807.762427] IP: ipv6_dev_get_saddr+0x8b/0x1d0
[940807.815725] PGD 0 P4D 0
[940807.847173] Oops: 0000 [#1] SMP PTI
[940807.890073] Modules linked in:
[940807.927765] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G        W        4.16.0-rc1-seg6bpf+ #2
[940808.028988] Hardware name: HP ProLiant DL120 G6/ProLiant DL120 G6, BIOS O26    09/06/2010
[940808.128128] RIP: 0010:ipv6_dev_get_saddr+0x8b/0x1d0
[940808.187667] RSP: 0018:ffff88043fd836b0 EFLAGS: 00010206
[940808.251366] RAX: 0000000000000005 RBX: ffff88042cb1c860 RCX: 00000000000000fe
[940808.338025] RDX: 00000000000002c0 RSI: ffff88042cb1c860 RDI: 0000000000004500
[940808.424683] RBP: ffff88043fd83740 R08: 0000000000000000 R09: ffffffffffffffff
[940808.511342] R10: 0000000000000040 R11: 0000000000000000 R12: ffff88042cb1c850
[940808.598012] R13: ffffffff8208e380 R14: ffff88042ac8da00 R15: 0000000000000002
[940808.684675] FS:  0000000000000000(0000) GS:ffff88043fd80000(0000) knlGS:0000000000000000
[940808.783036] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[940808.852975] CR2: 000000000000047c CR3: 00000004255fe000 CR4: 00000000000006e0
[940808.939634] Call Trace:
[940808.970041]  <IRQ>
[940808.995250]  ? ip6t_do_table+0x265/0x640
[940809.043341]  seg6_do_srh_encap+0x28f/0x300
[940809.093516]  ? seg6_do_srh+0x1a0/0x210
[940809.139528]  seg6_do_srh+0x1a0/0x210
[940809.183462]  seg6_output+0x28/0x1e0
[940809.226358]  lwtunnel_output+0x3f/0x70
[940809.272370]  ip6_xmit+0x2b8/0x530
[940809.313185]  ? ac6_proc_exit+0x20/0x20
[940809.359197]  inet6_csk_xmit+0x7d/0xc0
[940809.404173]  tcp_transmit_skb+0x548/0x9a0
[940809.453304]  __tcp_retransmit_skb+0x1a8/0x7a0
[940809.506603]  ? ip6_default_advmss+0x40/0x40
[940809.557824]  ? tcp_current_mss+0x24/0x90
[940809.605925]  tcp_retransmit_skb+0xd/0x80
[940809.654016]  tcp_xmit_retransmit_queue.part.17+0xf9/0x210
[940809.719797]  tcp_ack+0xa47/0x1110
[940809.760612]  tcp_rcv_established+0x13c/0x570
[940809.812865]  tcp_v6_do_rcv+0x151/0x3d0
[940809.858879]  tcp_v6_rcv+0xa5c/0xb10
[940809.901770]  ? seg6_output+0xdd/0x1e0
[940809.946745]  ip6_input_finish+0xbb/0x460
[940809.994837]  ip6_input+0x74/0x80
[940810.034612]  ? ip6_rcv_finish+0xb0/0xb0
[940810.081663]  ipv6_rcv+0x31c/0x4c0
...

Fixes: 6c8702c ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Reported-by: Tom Herbert <[email protected]>
Signed-off-by: David Lebrun <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
Dave Jones reported fs_reclaim lockdep warnings.

  ============================================
  WARNING: possible recursive locking detected
  4.15.0-rc9-backup-debug+ #1 Not tainted
  --------------------------------------------
  sshd/24800 is trying to acquire lock:
   (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30

  but task is already holding lock:
   (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(fs_reclaim);
    lock(fs_reclaim);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  2 locks held by sshd/24800:
   #0:  (sk_lock-AF_INET6){+.+.}, at: [<000000001a069652>] tcp_sendmsg+0x19/0x40
   #1:  (fs_reclaim){+.+.}, at: [<0000000084f438c2>] fs_reclaim_acquire.part.102+0x5/0x30

  stack backtrace:
  CPU: 3 PID: 24800 Comm: sshd Not tainted 4.15.0-rc9-backup-debug+ #1
  Call Trace:
   dump_stack+0xbc/0x13f
   __lock_acquire+0xa09/0x2040
   lock_acquire+0x12e/0x350
   fs_reclaim_acquire.part.102+0x29/0x30
   kmem_cache_alloc+0x3d/0x2c0
   alloc_extent_state+0xa7/0x410
   __clear_extent_bit+0x3ea/0x570
   try_release_extent_mapping+0x21a/0x260
   __btrfs_releasepage+0xb0/0x1c0
   btrfs_releasepage+0x161/0x170
   try_to_release_page+0x162/0x1c0
   shrink_page_list+0x1d5a/0x2fb0
   shrink_inactive_list+0x451/0x940
   shrink_node_memcg.constprop.88+0x4c9/0x5e0
   shrink_node+0x12d/0x260
   try_to_free_pages+0x418/0xaf0
   __alloc_pages_slowpath+0x976/0x1790
   __alloc_pages_nodemask+0x52c/0x5c0
   new_slab+0x374/0x3f0
   ___slab_alloc.constprop.81+0x47e/0x5a0
   __slab_alloc.constprop.80+0x32/0x60
   __kmalloc_track_caller+0x267/0x310
   __kmalloc_reserve.isra.40+0x29/0x80
   __alloc_skb+0xee/0x390
   sk_stream_alloc_skb+0xb8/0x340
   tcp_sendmsg_locked+0x8e6/0x1d30
   tcp_sendmsg+0x27/0x40
   inet_sendmsg+0xd0/0x310
   sock_write_iter+0x17a/0x240
   __vfs_write+0x2ab/0x380
   vfs_write+0xfb/0x260
   SyS_write+0xb6/0x140
   do_syscall_64+0x1e5/0xc05
   entry_SYSCALL64_slow_path+0x25/0x25

This warning is caused by commit d92a8cf ("locking/lockdep:
Rework FS_RECLAIM annotation") which replaced the use of
lockdep_{set,clear}_current_reclaim_state() in __perform_reclaim()
and lockdep_trace_alloc() in slab_pre_alloc_hook() with
fs_reclaim_acquire()/ fs_reclaim_release().

Since __kmalloc_reserve() from __alloc_skb() adds __GFP_NOMEMALLOC |
__GFP_NOWARN to gfp_mask, and all reclaim path simply propagates
__GFP_NOMEMALLOC, fs_reclaim_acquire() in slab_pre_alloc_hook() is
trying to grab the 'fake' lock again when __perform_reclaim() already
grabbed the 'fake' lock.

The

  /* this guy won't enter reclaim */
  if ((current->flags & PF_MEMALLOC) && !(gfp_mask & __GFP_NOMEMALLOC))
          return false;

test which causes slab_pre_alloc_hook() to try to grab the 'fake' lock
was added by commit cf40bd1 ("lockdep: annotate reclaim context
(__GFP_NOFS)").  But that test is outdated because PF_MEMALLOC thread
won't enter reclaim regardless of __GFP_NOMEMALLOC after commit
341ce06 ("page allocator: calculate the alloc_flags for allocation
only once") added the PF_MEMALLOC safeguard (

  /* Avoid recursion of direct reclaim */
  if (p->flags & PF_MEMALLOC)
          goto nopage;

in __alloc_pages_slowpath()).

Thus, let's fix outdated test by removing __GFP_NOMEMALLOC test and
allow __need_fs_reclaim() to return false.

Link: http://lkml.kernel.org/r/[email protected]
Fixes: d92a8cf ("locking/lockdep: Rework FS_RECLAIM annotation")
Signed-off-by: Tetsuo Handa <[email protected]>
Reported-by: Dave Jones <[email protected]>
Tested-by: Dave Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Nick Piggin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Nikolay Borisov <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: <[email protected]>	[4.14+]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
AlbanBedel pushed a commit that referenced this issue Mar 24, 2018
…ble"

This reverts commit b92df1d ("mm: page_alloc: skip over regions of
invalid pfns where possible").  The commit is meant to be a boot init
speed up skipping the loop in memmap_init_zone() for invalid pfns.

But given some specific memory mapping on x86_64 (or more generally
theoretically anywhere but on arm with CONFIG_HAVE_ARCH_PFN_VALID) the
implementation also skips valid pfns which is plain wrong and causes
'kernel BUG at mm/page_alloc.c:1389!'

  crash> log | grep -e BUG -e RIP -e Call.Trace -e move_freepages_block -e rmqueue -e freelist -A1
  kernel BUG at mm/page_alloc.c:1389!
  invalid opcode: 0000 [#1] SMP
  --
  RIP: 0010: move_freepages+0x15e/0x160
  --
  Call Trace:
    move_freepages_block+0x73/0x80
    __rmqueue+0x263/0x460
    get_page_from_freelist+0x7e1/0x9e0
    __alloc_pages_nodemask+0x176/0x420
  --

  crash> page_init_bug -v | grep RAM
  <struct resource 0xffff88067fffd2f8>          1000 -        9bfff       System RAM (620.00 KiB)
  <struct resource 0xffff88067fffd3a0>        100000 -     430bffff       System RAM (  1.05 GiB = 1071.75 MiB = 1097472.00 KiB)
  <struct resource 0xffff88067fffd410>      4b0c8000 -     4bf9cfff       System RAM ( 14.83 MiB = 15188.00 KiB)
  <struct resource 0xffff88067fffd480>      4bfac000 -     646b1fff       System RAM (391.02 MiB = 400408.00 KiB)
  <struct resource 0xffff88067fffd560>      7b788000 -     7b7fffff       System RAM (480.00 KiB)
  <struct resource 0xffff88067fffd640>     100000000 -    67fffffff       System RAM ( 22.00 GiB)

  crash> page_init_bug | head -6
  <struct resource 0xffff88067fffd560>      7b788000 -     7b7fffff       System RAM (480.00 KiB)
  <struct page 0xffffea0001ede200>   1fffff00000000  0 <struct pglist_data 0xffff88047ffd9000> 1 <struct zone 0xffff88047ffd9800> DMA32          4096    1048575
  <struct page 0xffffea0001ede200>       505736 505344 <struct page 0xffffea0001ed8000> 505855 <struct page 0xffffea0001edffc0>
  <struct page 0xffffea0001ed8000>                0  0 <struct pglist_data 0xffff88047ffd9000> 0 <struct zone 0xffff88047ffd9000> DMA               1       4095
  <struct page 0xffffea0001edffc0>   1fffff00000400  0 <struct pglist_data 0xffff88047ffd9000> 1 <struct zone 0xffff88047ffd9800> DMA32          4096    1048575
  BUG, zones differ!

  crash> kmem -p 77fff000 78000000 7b5ff000 7b600000 7b787000 7b788000
        PAGE        PHYSICAL      MAPPING       INDEX CNT FLAGS
  ffffea0001e00000  78000000                0        0  0 0
  ffffea0001ed7fc0  7b5ff000                0        0  0 0
  ffffea0001ed8000  7b600000                0        0  0 0       <<<<
  ffffea0001ede1c0  7b787000                0        0  0 0
  ffffea0001ede200  7b788000                0        0  1 1fffff00000000

Link: http://lkml.kernel.org/r/[email protected]
Fixes: b92df1d ("mm: page_alloc: skip over regions of invalid pfns where possible")
Signed-off-by: Daniel Vacek <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Pavel Tatashin <[email protected]>
Cc: Paul Burton <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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