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Bootloader offset #16

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nomis opened this issue May 7, 2012 · 23 comments
Closed

Bootloader offset #16

nomis opened this issue May 7, 2012 · 23 comments

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@nomis
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nomis commented May 7, 2012

Could the bootloader be changed to load kernel.img at 0x8000 and provide the instructions and data for the first 32K itself?

Alternatively it could load a separate file for the first 32K and then kernel.bin at 0x8000?

Then there's no need to put extra data on the start of the kernel image every time.

@popcornmix
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What's the motivation for this? Saving 32K of disk space? Making build process simpler? of is there a more significant benefit?
I'm a little wary of just changing the convention, as it makes it harder to switch kernels/firmware from before/after the event.
I could add a new config.txt setting to switch between the two behaviours.
I could see if md5sum of first 32K of kernel matches the normal version, and if not, then load it at 0x8000 and fill in the normal version's first32k. Any preference?

@nomis
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nomis commented May 8, 2012

The motivation is to make the build process simpler as it looks unlikely that the current process would ever get integrated with the kernel build process as the kernel shouldn't be including a fixed machine ID. It's also awkward even as a memory image that another bootloader then partially overwrites to provide arguments.

No one can use the first 32KB anyway because of the kernel arguments being written at 0x100.

I'm not sure what the best option is. I think the current boot process may loop if loaded at 0x8000.

@popcornmix
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The latest github start.elf supports config.txt option:
disable_commandline_tags=1
which avoids writing kernel arguments.

How about:
if (disable_commandline_tags=1) load kernel.img at 0. Don't fill in arguments.
else if (md5sum first32k matches) load kernel.img at 0 and fill in aguments (*)
else load kernel.img at 0x8000, GPU inserts first32K, and fills in aguments

Case (*) is deprecated and removed at some point in future.

@nomis
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nomis commented May 8, 2012

That sounds reasonable but you'll need to warn people that it's happening as I know haiku is already using a "b 0x8000" as the only opcode in the first 32KB.

bootc pushed a commit to bootc/linux-rpi-orig that referenced this issue May 8, 2012
…S block during isolation for migration

commit 0bf380b upstream.

When isolating for migration, migration starts at the start of a zone
which is not necessarily pageblock aligned.  Further, it stops isolating
when COMPACT_CLUSTER_MAX pages are isolated so migrate_pfn is generally
not aligned.  This allows isolate_migratepages() to call pfn_to_page() on
an invalid PFN which can result in a crash.  This was originally reported
against a 3.0-based kernel with the following trace in a crash dump.

PID: 9902   TASK: d47aecd0  CPU: 0   COMMAND: "memcg_process_s"
 #0 [d72d3ad0] crash_kexec at c028cfdb
 raspberrypi#1 [d72d3b24] oops_end at c05c5322
 raspberrypi#2 [d72d3b38] __bad_area_nosemaphore at c0227e60
 raspberrypi#3 [d72d3bec] bad_area at c0227fb6
 raspberrypi#4 [d72d3c00] do_page_fault at c05c72ec
 raspberrypi#5 [d72d3c80] error_code (via page_fault) at c05c47a4
    EAX: 00000000  EBX: 000c0000  ECX: 00000001  EDX: 00000807  EBP: 000c0000
    DS:  007b      ESI: 00000001  ES:  007b      EDI: f3000a80  GS:  6f50
    CS:  0060      EIP: c030b15a  ERR: ffffffff  EFLAGS: 00010002
 raspberrypi#6 [d72d3cb4] isolate_migratepages at c030b15a
 raspberrypi#7 [d72d3d14] zone_watermark_ok at c02d26cb
 raspberrypi#8 [d72d3d2c] compact_zone at c030b8de
 raspberrypi#9 [d72d3d68] compact_zone_order at c030bba1
raspberrypi#10 [d72d3db4] try_to_compact_pages at c030bc84
raspberrypi#11 [d72d3ddc] __alloc_pages_direct_compact at c02d61e7
raspberrypi#12 [d72d3e08] __alloc_pages_slowpath at c02d66c7
raspberrypi#13 [d72d3e78] __alloc_pages_nodemask at c02d6a97
raspberrypi#14 [d72d3eb8] alloc_pages_vma at c030a845
raspberrypi#15 [d72d3ed4] do_huge_pmd_anonymous_page at c03178eb
raspberrypi#16 [d72d3f00] handle_mm_fault at c02f36c6
raspberrypi#17 [d72d3f30] do_page_fault at c05c70ed
raspberrypi#18 [d72d3fb0] error_code (via page_fault) at c05c47a4
    EAX: b71ff00  EBX: 00000001  ECX: 00001600  EDX: 00000431
    DS:  007b      ESI: 08048950  ES:  007b      EDI: bfaa3788
    SS:  007b      ESP: bfaa36e0  EBP: bfaa3828  GS:  6f50
    CS:  0073      EIP: 080487c8  ERR: ffffffff  EFLAGS: 00010202

It was also reported by Herbert van den Bergh against 3.1-based kernel
with the following snippet from the console log.

BUG: unable to handle kernel paging request at 01c00008
IP: [<c0522399>] isolate_migratepages+0x119/0x390
*pdpt = 000000002f7ce001 *pde = 0000000000000000

It is expected that it also affects 3.2.x and current mainline.

The problem is that pfn_valid is only called on the first PFN being
checked and that PFN is not necessarily aligned.  Lets say we have a case
like this

H = MAX_ORDER_NR_PAGES boundary
| = pageblock boundary
m = cc->migrate_pfn
f = cc->free_pfn
o = memory hole

H------|------H------|----m-Hoooooo|ooooooH-f----|------H

The migrate_pfn is just below a memory hole and the free scanner is beyond
the hole.  When isolate_migratepages started, it scans from migrate_pfn to
migrate_pfn+pageblock_nr_pages which is now in a memory hole.  It checks
pfn_valid() on the first PFN but then scans into the hole where there are
not necessarily valid struct pages.

This patch ensures that isolate_migratepages calls pfn_valid when
necessary.

Reported-by: Herbert van den Bergh <[email protected]>
Tested-by: Herbert van den Bergh <[email protected]>
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Michal Nazarewicz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
@nomis
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nomis commented May 8, 2012

It looks like proper devicetree support makes things even more complicated because the bootloader is supposed to provide that information at 0x100, which implies that the ability to load a 32KB section from a separate file would be useful.

How you're going to get the extra parameters (serial number, etc.) to the kernel in that scenario I don't know...

@nomis
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nomis commented May 8, 2012

I think you could load a device tree blob from a file to 0x100 and append the ATAGs.

@bootc
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bootc commented May 9, 2012

If I understand this correctly then, the bootloader could have a device-tree mode. If there is a 'bcm2708.dtb' file in the boot partition, its contents is loaded at 0x100 instead of the ATAGS, and it could also assume that it should load the kernel at 0x8000 and put its own code at 0x0000 as necessary to setup r0/r1/r2 for kernel entry.

That way we kill several birds with one stone: device tree booting (with a .dtb file we can edit as things evolve) as well as removing the need for a custom kernel image, and the whole thing can be managed as a single transition without needing to specify special configuration options in config.txt.

Note that I don't know enough about device-tree yet to know exactly how the bootloader should insert kernel arguments into the device tree file.

@nomis
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nomis commented May 9, 2012

I'd suggest the .dtb file is named something other than bcm2708.dtb as there would need to be different files for different device models (e.g. rpi-model-b.dtb) so a generic filename, something like "kernel.dtb" would be less confusing than the hardware model.

@popcornmix
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I don't know a lot about device tree, but if you tell me what is neeed I can arrange for a dtb file to be loaded at 0x100.
Do you want existing ATAGS (e.g. cmdline.txt) to be added after the dtb file ?

@bootc
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bootc commented May 9, 2012

For full device tree support, we'd need the bootloader to load in the .dtb file and then edit the structure to add such things as memory size and command-line arguments added in. Device-tree should completely replace the ATAGS support.

@nomis
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nomis commented May 13, 2012

It should also provide the system serial number and the MAC address.

There isn't currently any code in Linux to get the serial number from device tree even though it's a generic part of the arm arch...

@nomis
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nomis commented May 14, 2012

It would also be natural for the display size/depth to be provided in the device tree instead of as module parameters.

@popcornmix
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If you provide me with a .dtb file, and explain where useful values should be inserted (ideally provide a C code function that parses/modifies the loaded .dtb), then I'll make the GPU do it.

I've implemented the optional first32k scheme described earlier. I'll share that later tonight after some testing. It also has the UART setup.

@nomis
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nomis commented May 14, 2012

The list of DMA channels should also be provided (although I've not added a suitable device to the .dts file for that yet).

I don't know that much about .dtb files, but you can find the .dts in my rpi-linear branch as arch/arm/boot/dts/bcm2835.dts (this branch will currently boot with uart0 and the display but has no usb or mmc support). [You need to provide the .dtb at 0x100 via r2 or configure it to be appended to the kernel image (and then append it yourself) otherwise it won't boot]

Running "make dtbs" will create arch/arm/boot/bcm2835.dtb if you have the BCM2708 arch configured.

This file in the kernel source is strictly a convenience template, so it would be ok to put in placeholders to aid the bootloader. Everything's be32 so it should be simple to overwrite default values as required. There's already a placeholder for the memory.

@nomis
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nomis commented May 14, 2012

The memory area to use (i.e. L2 on/off) could also be provided in the device tree although I haven't looked into how the kernel could reconfigure those at runtime.

@nomis
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nomis commented May 14, 2012

There's libfdt for manipulating the .dtb here: git://git.jdl.com/software/dtc.git (dual GPL/BSD so you'd be able to use it).

@popcornmix
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So how do you want it loaded?
config.txt options:
device_tree=bcm2835.dtb (possibly that will be a default in future)
device_tree_address=0x100 (again the default)
GPU will then load it at 0x100, and overwrite the fields it knows about.
Does the code at 0x0 set r2? Should I modify that?

@nomis
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nomis commented May 14, 2012

Yes, the code at 0x0 should set r2 to the device_tree_address

@popcornmix
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Okay, a test firmware:
http://dl.dropbox.com/u/3669512/start.elf

This should support:
CONFIG_STR(device_tree)
CONFIG(device_tree_address)
CONFIG(kernel_address)
CONFIG(disable_commandline_tags)

It also sets up the UART to 115200 with a 3MHz clock as requested elsewhere. You can modify these:
CONFIG(init_uart_baud)
CONFIG(init_uart_clock)

So, as described start32k is now optional (and should be removed from kernel.img when using device tree)
You can load a device_tree with
device_tree=bcm2835.dtb
device_tree_address=0x100
r2 should be set to this address is initial code.
I don't (yet) modify the device tree

I did try parsing the device tree from GPU and it looked okay (http://pastebin.com/ty66Jies)

@nomis
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nomis commented May 14, 2012

This works for me!

[ 0.000000] Machine: BCM2708, model: BCM2835
[ 0.000000] Memory: 192MB = 192MB total
[ 0.000000] bank0: VIC at 0x2000b200 (8 IRQs)
[ 0.000000] bank1: VIC at 0x2000b204 (32 IRQs)
[ 0.000000] bank2: VIC at 0x2000b208 (32 IRQs)
[ 0.000000] sched_clock: 32 bits at 1000kHz, resolution 1000ns, wraps every 4294967ms
[ 0.000000] timer1: timer at MMIO 0x20003010 (irq = 1)
[ 0.000000] timer3: timer at MMIO 0x20003018 (irq = 3)
[ 0.112351] Serial: AMBA PL011 UART driver
[ 0.113869] 20201000.uart0: ttyAMA0 at MMIO 0x20201000 (irq = 57) is a PL011 rev3
[ 0.696930] console [ttyAMA0] enabled
[ 0.703394] bcm-mbox: Broadcom VideoCore Mailbox driver
[ 0.709829] bcm-mbox 2000b880.mbox0: mailbox at MMIO 0x2000b880 (irq = 65, channels = 0x000b)
[ 0.719777] stc: 32-bit clock at MMIO 0x20003004, 1000000 Hz
[ 0.754826] Switching to clocksource stc
[ 1.964569] bcm2708_fb display.0: registering framebuffer (800x480@16)
[ 1.985666] Console: switching to colour frame buffer device 100x30
[ 2.001894] bcm2708_wdog: default timeout=16 (nowayout=0)
[ 2.012992] bcm2708_wdog 20100000.watchdog: at MMIO 0x20100000
[ 2.124425] Freeing init memory: 10304K

At that point it waits forever for mmc0 as I was using cmdline.txt instead of the default :)

@kallisti5
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aaah... just when we get Haiku uart working :) Thanks for all the hard work on this guys.

@popcornmix
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Firmware now pushed to github. Please close issue if happy.

@nomis
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nomis commented May 17, 2012

The bootloader is able to load the kernel at 0x8000 and the device tree file at 0x100 so I'll close this issue and raise another one specifically on the device tree population.

@nomis nomis closed this as completed May 17, 2012
popcornmix pushed a commit to popcornmix/linux that referenced this issue Aug 16, 2012
…d reasons

commit 5cf02d0 upstream.

We've had some reports of a deadlock where rpciod ends up with a stack
trace like this:

    PID: 2507   TASK: ffff88103691ab40  CPU: 14  COMMAND: "rpciod/14"
     #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9
     raspberrypi#1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs]
     raspberrypi#2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f
     raspberrypi#3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8
     raspberrypi#4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs]
     raspberrypi#5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs]
     raspberrypi#6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670
     raspberrypi#7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271
     raspberrypi#8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638
     raspberrypi#9 [ffff8810343bf818] shrink_zone at ffffffff8112788f
    raspberrypi#10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e
    raspberrypi#11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f
    raspberrypi#12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad
    raspberrypi#13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942
    raspberrypi#14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a
    raspberrypi#15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9
    raspberrypi#16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b
    raspberrypi#17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808
    raspberrypi#18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c
    raspberrypi#19 [ffff8810343bfce8] inet_create at ffffffff81483ba6
    raspberrypi#20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7
    raspberrypi#21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc]
    raspberrypi#22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc]
    raspberrypi#23 [ffff8810343bfe38] worker_thread at ffffffff810887d0
    raspberrypi#24 [ffff8810343bfee8] kthread at ffffffff8108dd96
    raspberrypi#25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca

rpciod is trying to allocate memory for a new socket to talk to the
server. The VM ends up calling ->releasepage to get more memory, and it
tries to do a blocking commit. That commit can't succeed however without
a connected socket, so we deadlock.

Fix this by setting PF_FSTRANS on the workqueue task prior to doing the
socket allocation, and having nfs_release_page check for that flag when
deciding whether to do a commit call. Also, set PF_FSTRANS
unconditionally in rpc_async_schedule since that function can also do
allocations sometimes.

Signed-off-by: Jeff Layton <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Ben Hutchings <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 13, 2012
Printing the "start_ip" for every secondary cpu is very noisy on a large
system - and doesn't add any value. Drop this message.

Console log before:
Booting Node   0, Processors  #1
smpboot cpu 1: start_ip = 96000
 #2
smpboot cpu 2: start_ip = 96000
 #3
smpboot cpu 3: start_ip = 96000
 #4
smpboot cpu 4: start_ip = 96000
       ...
 #31
smpboot cpu 31: start_ip = 96000
Brought up 32 CPUs

Console log after:
Booting Node   0, Processors  #1 #2 #3 #4 #5 #6 #7 Ok.
Booting Node   1, Processors  #8 #9 #10 #11 #12 #13 #14 #15 Ok.
Booting Node   0, Processors  #16 #17 #18 #19 #20 #21 #22 #23 Ok.
Booting Node   1, Processors  #24 #25 #26 #27 #28 #29 #30 #31
Brought up 32 CPUs

Acked-by: Borislav Petkov <[email protected]>
Signed-off-by: Tony Luck <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 13, 2012
Add a parameter to avoid using MSI/MSI-X for PCIe native hotplug; it's
known to be buggy on some platforms.

In my environment, while shutting down, following stack trace is shown
sometimes.

  irq 16: nobody cared (try booting with the "irqpoll" option)
  Pid: 1081, comm: reboot Not tainted 3.2.0 #1
  Call Trace:
   <IRQ>  [<ffffffff810cec1d>] __report_bad_irq+0x3d/0xe0
   [<ffffffff810cee1c>] note_interrupt+0x15c/0x210
   [<ffffffff810cc485>] handle_irq_event_percpu+0xb5/0x210
   [<ffffffff810cc621>] handle_irq_event+0x41/0x70
   [<ffffffff810cf675>] handle_fasteoi_irq+0x55/0xc0
   [<ffffffff81015356>] handle_irq+0x46/0xb0
   [<ffffffff814fbe9d>] do_IRQ+0x5d/0xe0
   [<ffffffff814f146e>] common_interrupt+0x6e/0x6e
   [<ffffffff8106b040>] ? __do_softirq+0x60/0x210
   [<ffffffff8108aeb1>] ? hrtimer_interrupt+0x151/0x240
   [<ffffffff814fb5ec>] call_softirq+0x1c/0x30
   [<ffffffff810152d5>] do_softirq+0x65/0xa0
   [<ffffffff8106ae9d>] irq_exit+0xbd/0xe0
   [<ffffffff814fbf8e>] smp_apic_timer_interrupt+0x6e/0x99
   [<ffffffff814f9e5e>] apic_timer_interrupt+0x6e/0x80
   <EOI>  [<ffffffff814f0fb1>] ? _raw_spin_unlock_irqrestore+0x11/0x20
   [<ffffffff812629fc>] pci_bus_write_config_word+0x6c/0x80
   [<ffffffff81266fc2>] pci_intx+0x52/0xa0
   [<ffffffff8127de3d>] pci_intx_for_msi+0x1d/0x30
  [<ffffffff8127e4fb>] pci_msi_shutdown+0x7b/0x110
   [<ffffffff81269d34>] pci_device_shutdown+0x34/0x50
   [<ffffffff81326c4f>] device_shutdown+0x2f/0x140
   [<ffffffff8107b981>] kernel_restart_prepare+0x31/0x40
   [<ffffffff8107b9e6>] kernel_restart+0x16/0x60
   [<ffffffff8107bbfd>] sys_reboot+0x1ad/0x220
   [<ffffffff814f4b90>] ? do_page_fault+0x1e0/0x460
   [<ffffffff811942d0>] ? __sync_filesystem+0x90/0x90
   [<ffffffff8105c9aa>] ? __cond_resched+0x2a/0x40
   [<ffffffff814ef090>] ? _cond_resched+0x30/0x40
   [<ffffffff81169e17>] ? iterate_supers+0xb7/0xd0
   [<ffffffff814f9382>] system_call_fastpath+0x16/0x1b
  handlers:
  [<ffffffff8138a0f0>] usb_hcd_irq
  [<ffffffff8138a0f0>] usb_hcd_irq
  [<ffffffff8138a0f0>] usb_hcd_irq
  Disabling IRQ #16

An un-wanted interrupt is generated when PCI driver switches from
MSI/MSI-X to INTx while shutting down the device.  The interrupt does
not happen if MSI/MSI-X is not used on the device.
I confirmed that this problem does not happen if pcie_hp=nomsi was
specified and hotplug operation worked fine as usual.

v2: Automatically disable MSI/MSI-X against following device:
    PCI bridge: Integrated Device Technology, Inc. Device 807f (rev 02)
v3: Based on the review comment, combile the if statements.
v4: Removed module parameter.
    Move some code to build pciehp as a module.
    Move device specific code to driver/pci/quirks.c.
v5: Drop a device specific code until getting a vendor statement.

Reviewed-by: Kenji Kaneshige <[email protected]>
Signed-off-by: MUNEDA Takahiro <[email protected]>
Signed-off-by: Jesse Barnes <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 13, 2012
Fixes a lockdep warning:

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
net/mac80211/agg-rx.c:148 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 1
1 lock held by arecord/11226:
 #0:  (&tid_agg_rx->session_timer){+.-...}, at: [<ffffffff81066bb0>] call_timer_fn+0x0/0x360

stack backtrace:
Pid: 11226, comm: arecord Not tainted 3.1.0-kml #16
Call Trace:
 <IRQ>  [<ffffffff81093454>] lockdep_rcu_dereference+0xa4/0xc0
 [<ffffffffa02778c9>] sta_rx_agg_session_timer_expired+0xc9/0x110 [mac80211]
 [<ffffffffa0277800>] ? ieee80211_process_addba_resp+0x220/0x220 [mac80211]
 [<ffffffff81066c3a>] call_timer_fn+0x8a/0x360
 [<ffffffff81066bb0>] ? init_timer_deferrable_key+0x30/0x30
 [<ffffffff81477bb0>] ? _raw_spin_unlock_irq+0x30/0x70
 [<ffffffff81067049>] run_timer_softirq+0x139/0x310
 [<ffffffff81091d5e>] ? put_lock_stats.isra.25+0xe/0x40
 [<ffffffff810922ac>] ? lock_release_holdtime.part.26+0xdc/0x160
 [<ffffffffa0277800>] ? ieee80211_process_addba_resp+0x220/0x220 [mac80211]
 [<ffffffff8105cb78>] __do_softirq+0xc8/0x3c0
 [<ffffffff8108f088>] ? tick_dev_program_event+0x48/0x110
 [<ffffffff8108f16f>] ? tick_program_event+0x1f/0x30
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff8147a43c>] call_softirq+0x1c/0x30
 [<ffffffff81004c55>] do_softirq+0xa5/0xe0
 [<ffffffff8105d1ee>] irq_exit+0xae/0xe0
 [<ffffffff8147ac6b>] smp_apic_timer_interrupt+0x6b/0x98
 [<ffffffff81479ab3>] apic_timer_interrupt+0x73/0x80
 <EOI>  [<ffffffff8146aac6>] ? free_debug_processing+0x1a1/0x1d5
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff8146ab2b>] __slab_free+0x31/0x2ca
 [<ffffffff81477c3a>] ? _raw_spin_unlock_irqrestore+0x4a/0x90
 [<ffffffff81253b8f>] ? __debug_check_no_obj_freed+0x15f/0x210
 [<ffffffff81097054>] ? lock_release_nested+0x84/0xc0
 [<ffffffff8113ec55>] ? kmem_cache_free+0x105/0x250
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff8113ed8f>] kmem_cache_free+0x23f/0x250
 [<ffffffff81153b15>] putname+0x35/0x50
 [<ffffffff81146d8d>] do_sys_open+0x16d/0x1d0
 [<ffffffff81146e10>] sys_open+0x20/0x30
 [<ffffffff81478f42>] system_call_fastpath+0x16/0x1b

Reported-by: Johannes Berg <[email protected]>
Signed-off-by: Felix Fietkau <[email protected]>
Signed-off-by: John W. Linville <[email protected]>
popcornmix pushed a commit that referenced this issue Feb 8, 2024
[ Upstream commit 55a8210 ]

When processing a packed profile in unpack_profile() described like

 "profile :ns::samba-dcerpcd /usr/lib*/samba/{,samba/}samba-dcerpcd {...}"

a string ":samba-dcerpcd" is unpacked as a fully-qualified name and then
passed to aa_splitn_fqname().

aa_splitn_fqname() treats ":samba-dcerpcd" as only containing a namespace.
Thus it returns NULL for tmpname, meanwhile tmpns is non-NULL. Later
aa_alloc_profile() crashes as the new profile name is NULL now.

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 6 PID: 1657 Comm: apparmor_parser Not tainted 6.7.0-rc2-dirty #16
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
RIP: 0010:strlen+0x1e/0xa0
Call Trace:
 <TASK>
 ? strlen+0x1e/0xa0
 aa_policy_init+0x1bb/0x230
 aa_alloc_profile+0xb1/0x480
 unpack_profile+0x3bc/0x4960
 aa_unpack+0x309/0x15e0
 aa_replace_profiles+0x213/0x33c0
 policy_update+0x261/0x370
 profile_replace+0x20e/0x2a0
 vfs_write+0x2af/0xe00
 ksys_write+0x126/0x250
 do_syscall_64+0x46/0xf0
 entry_SYSCALL_64_after_hwframe+0x6e/0x76
 </TASK>
---[ end trace 0000000000000000 ]---
RIP: 0010:strlen+0x1e/0xa0

It seems such behaviour of aa_splitn_fqname() is expected and checked in
other places where it is called (e.g. aa_remove_profiles). Well, there
is an explicit comment "a ns name without a following profile is allowed"
inside.

AFAICS, nothing can prevent unpacked "name" to be in form like
":samba-dcerpcd" - it is passed from userspace.

Deny the whole profile set replacement in such case and inform user with
EPROTO and an explaining message.

Found by Linux Verification Center (linuxtesting.org).

Fixes: 04dc715 ("apparmor: audit policy ns specified in policy load")
Signed-off-by: Fedor Pchelkin <[email protected]>
Signed-off-by: John Johansen <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Apr 23, 2024
vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <[email protected]>
Reviewed-by: Willem de Bruijn <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
popcornmix pushed a commit that referenced this issue Apr 29, 2024
[ Upstream commit f8bbc07 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <[email protected]>
Reviewed-by: Willem de Bruijn <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Apr 29, 2024
[ Upstream commit f8bbc07 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <[email protected]>
Reviewed-by: Willem de Bruijn <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue May 13, 2024
With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To
thwart invalid memory accesses, the JITs add an exception table entry
for all such accesses. But in case the src_reg + offset is a userspace
address, the BPF program might read that memory if the user has
mapped it.

Make the verifier add guard instructions around such memory accesses and
skip the load if the address falls into the userspace region.

The JITs need to implement bpf_arch_uaddress_limit() to define where
the userspace addresses end for that architecture or TASK_SIZE is taken
as default.

The implementation is as follows:

REG_AX =  SRC_REG
if(offset)
	REG_AX += offset;
REG_AX >>= 32;
if (REG_AX <= (uaddress_limit >> 32))
	DST_REG = 0;
else
	DST_REG = *(size *)(SRC_REG + offset);

Comparing just the upper 32 bits of the load address with the upper
32 bits of uaddress_limit implies that the values are being aligned down
to a 4GB boundary before comparison.

The above means that all loads with address <= uaddress_limit + 4GB are
skipped. This is acceptable because there is a large hole (much larger
than 4GB) between userspace and kernel space memory, therefore a
correctly functioning BPF program should not access this 4GB memory
above the userspace.

Let's analyze what this patch does to the following fentry program
dereferencing an untrusted pointer:

  SEC("fentry/tcp_v4_connect")
  int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk)
  {
                *(volatile long *)sk;
                return 0;
  }

    BPF Program before              |           BPF Program after
    ------------------              |           -----------------

  0: (79) r1 = *(u64 *)(r1 +0)          0: (79) r1 = *(u64 *)(r1 +0)
  -----------------------------------------------------------------------
  1: (79) r1 = *(u64 *)(r1 +0) --\      1: (bf) r11 = r1
  ----------------------------\   \     2: (77) r11 >>= 32
  2: (b7) r0 = 0               \   \    3: (b5) if r11 <= 0x8000 goto pc+2
  3: (95) exit                  \   \-> 4: (79) r1 = *(u64 *)(r1 +0)
                                 \      5: (05) goto pc+1
                                  \     6: (b7) r1 = 0
                                   \--------------------------------------
                                        7: (b7) r0 = 0
                                        8: (95) exit

As you can see from above, in the best case (off=0), 5 extra instructions
are emitted.

Now, we analyze the same program after it has gone through the JITs of
ARM64 and RISC-V architectures. We follow the single load instruction
that has the untrusted pointer and see what instrumentation has been
added around it.

                                x86-64 JIT
                                ==========
     JIT's Instrumentation
          (upstream)
     ---------------------

   0:   nopl   0x0(%rax,%rax,1)
   5:   xchg   %ax,%ax
   7:   push   %rbp
   8:   mov    %rsp,%rbp
   b:   mov    0x0(%rdi),%rdi
  ---------------------------------
   f:   movabs $0x800000000000,%r11
  19:   cmp    %r11,%rdi
  1c:   jb     0x000000000000002a
  1e:   mov    %rdi,%r11
  21:   add    $0x0,%r11
  28:   jae    0x000000000000002e
  2a:   xor    %edi,%edi
  2c:   jmp    0x0000000000000032
  2e:   mov    0x0(%rdi),%rdi
  ---------------------------------
  32:   xor    %eax,%eax
  34:   leave
  35:   ret

The x86-64 JIT already emits some instructions to protect against user
memory access. This patch doesn't make any changes for the x86-64 JIT.

                                  ARM64 JIT
                                  =========

        No Intrumentation                       Verifier's Instrumentation
           (upstream)                                  (This patch)
        -----------------                       --------------------------

   0:   add     x9, x30, #0x0                0:   add     x9, x30, #0x0
   4:   nop                                  4:   nop
   8:   paciasp                              8:   paciasp
   c:   stp     x29, x30, [sp, #-16]!        c:   stp     x29, x30, [sp, #-16]!
  10:   mov     x29, sp                     10:   mov     x29, sp
  14:   stp     x19, x20, [sp, #-16]!       14:   stp     x19, x20, [sp, #-16]!
  18:   stp     x21, x22, [sp, #-16]!       18:   stp     x21, x22, [sp, #-16]!
  1c:   stp     x25, x26, [sp, #-16]!       1c:   stp     x25, x26, [sp, #-16]!
  20:   stp     x27, x28, [sp, #-16]!       20:   stp     x27, x28, [sp, #-16]!
  24:   mov     x25, sp                     24:   mov     x25, sp
  28:   mov     x26, #0x0                   28:   mov     x26, #0x0
  2c:   sub     x27, x25, #0x0              2c:   sub     x27, x25, #0x0
  30:   sub     sp, sp, #0x0                30:   sub     sp, sp, #0x0
  34:   ldr     x0, [x0]                    34:   ldr     x0, [x0]
--------------------------------------------------------------------------------
  38:   ldr     x0, [x0] ----------\        38:   add     x9, x0, #0x0
-----------------------------------\\       3c:   lsr     x9, x9, #32
  3c:   mov     x7, #0x0            \\      40:   cmp     x9, #0x10, lsl #12
  40:   mov     sp, sp               \\     44:   b.ls    0x0000000000000050
  44:   ldp     x27, x28, [sp], #16   \\--> 48:   ldr     x0, [x0]
  48:   ldp     x25, x26, [sp], #16    \    4c:   b       0x0000000000000054
  4c:   ldp     x21, x22, [sp], #16     \   50:   mov     x0, #0x0
  50:   ldp     x19, x20, [sp], #16      \---------------------------------------
  54:   ldp     x29, x30, [sp], #16         54:   mov     x7, #0x0
  58:   add     x0, x7, #0x0                58:   mov     sp, sp
  5c:   autiasp                             5c:   ldp     x27, x28, [sp], #16
  60:   ret                                 60:   ldp     x25, x26, [sp], #16
  64:   nop                                 64:   ldp     x21, x22, [sp], #16
  68:   ldr     x10, 0x0000000000000070     68:   ldp     x19, x20, [sp], #16
  6c:   br      x10                         6c:   ldp     x29, x30, [sp], #16
                                            70:   add     x0, x7, #0x0
                                            74:   autiasp
                                            78:   ret
                                            7c:   nop
                                            80:   ldr     x10, 0x0000000000000088
                                            84:   br      x10

There are 6 extra instructions added in ARM64 in the best case. This will
become 7 in the worst case (off != 0).

                           RISC-V JIT (RISCV_ISA_C Disabled)
                           ==========

        No Intrumentation           Verifier's Instrumentation
           (upstream)                      (This patch)
        -----------------           --------------------------

   0:   nop                            0:   nop
   4:   nop                            4:   nop
   8:   li      a6, 33                 8:   li      a6, 33
   c:   addi    sp, sp, -16            c:   addi    sp, sp, -16
  10:   sd      s0, 8(sp)             10:   sd      s0, 8(sp)
  14:   addi    s0, sp, 16            14:   addi    s0, sp, 16
  18:   ld      a0, 0(a0)             18:   ld      a0, 0(a0)
---------------------------------------------------------------
  1c:   ld      a0, 0(a0) --\         1c:   mv      t0, a0
--------------------------\  \        20:   srli    t0, t0, 32
  20:   li      a5, 0      \  \       24:   lui     t1, 4096
  24:   ld      s0, 8(sp)   \  \      28:   sext.w  t1, t1
  28:   addi    sp, sp, 16   \  \     2c:   bgeu    t1, t0, 12
  2c:   sext.w  a0, a5        \  \--> 30:   ld      a0, 0(a0)
  30:   ret                    \      34:   j       8
                                \     38:   li      a0, 0
                                 \------------------------------
                                      3c:   li      a5, 0
                                      40:   ld      s0, 8(sp)
                                      44:   addi    sp, sp, 16
                                      48:   sext.w  a0, a5
                                      4c:   ret

There are 7 extra instructions added in RISC-V.

Fixes: 8008342 ("bpf, arm64: Add BPF exception tables")
Reported-by: Breno Leitao <[email protected]>
Suggested-by: Alexei Starovoitov <[email protected]>
Acked-by: Ilya Leoshkevich <[email protected]>
Signed-off-by: Puranjay Mohan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 10, 2024
We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: [email protected] # 6.1+
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Signed-off-by: David Sterba <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 12, 2024
[ Upstream commit 769e6a1 ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Ben Gainey <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Li Dong <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Oliver Upton <[email protected]>
Cc: Paran Lee <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sun Haiyong <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: Yicong Yang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 12, 2024
[ Upstream commit 769e6a1 ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Ben Gainey <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Li Dong <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Oliver Upton <[email protected]>
Cc: Paran Lee <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sun Haiyong <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: Yicong Yang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 17, 2024
commit 9d274c1 upstream.

We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: [email protected] # 6.1+
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 17, 2024
commit 9d274c1 upstream.

We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: [email protected] # 6.1+
Reviewed-by: Filipe Manana <[email protected]>
Signed-off-by: Omar Sandoval <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 17, 2024
When queues are started, netif_napi_add() and napi_enable() are called.
If there are 4 queues and only 3 queues are used for the current
configuration, only 3 queues' napi should be registered and enabled.
The ionic_qcq_enable() checks whether the .poll pointer is not NULL for
enabling only the using queue' napi. Unused queues' napi will not be
registered by netif_napi_add(), so the .poll pointer indicates NULL.
But it couldn't distinguish whether the napi was unregistered or not
because netif_napi_del() doesn't reset the .poll pointer to NULL.
So, ionic_qcq_enable() calls napi_enable() for the queue, which was
unregistered by netif_napi_del().

Reproducer:
   ethtool -L <interface name> rx 1 tx 1 combined 0
   ethtool -L <interface name> rx 0 tx 0 combined 1
   ethtool -L <interface name> rx 0 tx 0 combined 4

Splat looks like:
kernel BUG at net/core/dev.c:6666!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 1057 Comm: kworker/3:3 Not tainted 6.10.0-rc2+ #16
Workqueue: events ionic_lif_deferred_work [ionic]
RIP: 0010:napi_enable+0x3b/0x40
Code: 48 89 c2 48 83 e2 f6 80 b9 61 09 00 00 00 74 0d 48 83 bf 60 01 00 00 00 74 03 80 ce 01 f0 4f
RSP: 0018:ffffb6ed83227d48 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff97560cda0828 RCX: 0000000000000029
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff97560cda0a28
RBP: ffffb6ed83227d50 R08: 0000000000000400 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff97560ce3c1a0 R14: 0000000000000000 R15: ffff975613ba0a20
FS:  0000000000000000(0000) GS:ffff975d5f780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8f734ee200 CR3: 0000000103e50000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
 <TASK>
 ? die+0x33/0x90
 ? do_trap+0xd9/0x100
 ? napi_enable+0x3b/0x40
 ? do_error_trap+0x83/0xb0
 ? napi_enable+0x3b/0x40
 ? napi_enable+0x3b/0x40
 ? exc_invalid_op+0x4e/0x70
 ? napi_enable+0x3b/0x40
 ? asm_exc_invalid_op+0x16/0x20
 ? napi_enable+0x3b/0x40
 ionic_qcq_enable+0xb7/0x180 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_start_queues+0xc4/0x290 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_link_status_check+0x11c/0x170 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_lif_deferred_work+0x129/0x280 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 process_one_work+0x145/0x360
 worker_thread+0x2bb/0x3d0
 ? __pfx_worker_thread+0x10/0x10
 kthread+0xcc/0x100
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x2d/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30

Fixes: 0f3154e ("ionic: Add Tx and Rx handling")
Signed-off-by: Taehee Yoo <[email protected]>
Reviewed-by: Brett Creeley <[email protected]>
Reviewed-by: Shannon Nelson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 17, 2024
[ Upstream commit 769e6a1 ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Ben Gainey <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Li Dong <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Oliver Upton <[email protected]>
Cc: Paran Lee <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sun Haiyong <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: Yicong Yang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 24, 2024
[ Upstream commit 79f18a4 ]

When queues are started, netif_napi_add() and napi_enable() are called.
If there are 4 queues and only 3 queues are used for the current
configuration, only 3 queues' napi should be registered and enabled.
The ionic_qcq_enable() checks whether the .poll pointer is not NULL for
enabling only the using queue' napi. Unused queues' napi will not be
registered by netif_napi_add(), so the .poll pointer indicates NULL.
But it couldn't distinguish whether the napi was unregistered or not
because netif_napi_del() doesn't reset the .poll pointer to NULL.
So, ionic_qcq_enable() calls napi_enable() for the queue, which was
unregistered by netif_napi_del().

Reproducer:
   ethtool -L <interface name> rx 1 tx 1 combined 0
   ethtool -L <interface name> rx 0 tx 0 combined 1
   ethtool -L <interface name> rx 0 tx 0 combined 4

Splat looks like:
kernel BUG at net/core/dev.c:6666!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 1057 Comm: kworker/3:3 Not tainted 6.10.0-rc2+ #16
Workqueue: events ionic_lif_deferred_work [ionic]
RIP: 0010:napi_enable+0x3b/0x40
Code: 48 89 c2 48 83 e2 f6 80 b9 61 09 00 00 00 74 0d 48 83 bf 60 01 00 00 00 74 03 80 ce 01 f0 4f
RSP: 0018:ffffb6ed83227d48 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff97560cda0828 RCX: 0000000000000029
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff97560cda0a28
RBP: ffffb6ed83227d50 R08: 0000000000000400 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff97560ce3c1a0 R14: 0000000000000000 R15: ffff975613ba0a20
FS:  0000000000000000(0000) GS:ffff975d5f780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8f734ee200 CR3: 0000000103e50000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
 <TASK>
 ? die+0x33/0x90
 ? do_trap+0xd9/0x100
 ? napi_enable+0x3b/0x40
 ? do_error_trap+0x83/0xb0
 ? napi_enable+0x3b/0x40
 ? napi_enable+0x3b/0x40
 ? exc_invalid_op+0x4e/0x70
 ? napi_enable+0x3b/0x40
 ? asm_exc_invalid_op+0x16/0x20
 ? napi_enable+0x3b/0x40
 ionic_qcq_enable+0xb7/0x180 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_start_queues+0xc4/0x290 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_link_status_check+0x11c/0x170 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_lif_deferred_work+0x129/0x280 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 process_one_work+0x145/0x360
 worker_thread+0x2bb/0x3d0
 ? __pfx_worker_thread+0x10/0x10
 kthread+0xcc/0x100
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x2d/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30

Fixes: 0f3154e ("ionic: Add Tx and Rx handling")
Signed-off-by: Taehee Yoo <[email protected]>
Reviewed-by: Brett Creeley <[email protected]>
Reviewed-by: Shannon Nelson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Jun 24, 2024
[ Upstream commit 79f18a4 ]

When queues are started, netif_napi_add() and napi_enable() are called.
If there are 4 queues and only 3 queues are used for the current
configuration, only 3 queues' napi should be registered and enabled.
The ionic_qcq_enable() checks whether the .poll pointer is not NULL for
enabling only the using queue' napi. Unused queues' napi will not be
registered by netif_napi_add(), so the .poll pointer indicates NULL.
But it couldn't distinguish whether the napi was unregistered or not
because netif_napi_del() doesn't reset the .poll pointer to NULL.
So, ionic_qcq_enable() calls napi_enable() for the queue, which was
unregistered by netif_napi_del().

Reproducer:
   ethtool -L <interface name> rx 1 tx 1 combined 0
   ethtool -L <interface name> rx 0 tx 0 combined 1
   ethtool -L <interface name> rx 0 tx 0 combined 4

Splat looks like:
kernel BUG at net/core/dev.c:6666!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 1057 Comm: kworker/3:3 Not tainted 6.10.0-rc2+ #16
Workqueue: events ionic_lif_deferred_work [ionic]
RIP: 0010:napi_enable+0x3b/0x40
Code: 48 89 c2 48 83 e2 f6 80 b9 61 09 00 00 00 74 0d 48 83 bf 60 01 00 00 00 74 03 80 ce 01 f0 4f
RSP: 0018:ffffb6ed83227d48 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff97560cda0828 RCX: 0000000000000029
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff97560cda0a28
RBP: ffffb6ed83227d50 R08: 0000000000000400 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: ffff97560ce3c1a0 R14: 0000000000000000 R15: ffff975613ba0a20
FS:  0000000000000000(0000) GS:ffff975d5f780000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8f734ee200 CR3: 0000000103e50000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
 <TASK>
 ? die+0x33/0x90
 ? do_trap+0xd9/0x100
 ? napi_enable+0x3b/0x40
 ? do_error_trap+0x83/0xb0
 ? napi_enable+0x3b/0x40
 ? napi_enable+0x3b/0x40
 ? exc_invalid_op+0x4e/0x70
 ? napi_enable+0x3b/0x40
 ? asm_exc_invalid_op+0x16/0x20
 ? napi_enable+0x3b/0x40
 ionic_qcq_enable+0xb7/0x180 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_start_queues+0xc4/0x290 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_link_status_check+0x11c/0x170 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 ionic_lif_deferred_work+0x129/0x280 [ionic 59bdfc8a035436e1c4224ff7d10789e3f14643f8]
 process_one_work+0x145/0x360
 worker_thread+0x2bb/0x3d0
 ? __pfx_worker_thread+0x10/0x10
 kthread+0xcc/0x100
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x2d/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30

Fixes: 0f3154e ("ionic: Add Tx and Rx handling")
Signed-off-by: Taehee Yoo <[email protected]>
Reviewed-by: Brett Creeley <[email protected]>
Reviewed-by: Shannon Nelson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Jul 1, 2024
The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
popcornmix pushed a commit that referenced this issue Jul 8, 2024
commit be346c1 upstream.

The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix pushed a commit that referenced this issue Jul 8, 2024
commit be346c1 upstream.

The code in ocfs2_dio_end_io_write() estimates number of necessary
transaction credits using ocfs2_calc_extend_credits().  This however does
not take into account that the IO could be arbitrarily large and can
contain arbitrary number of extents.

Extent tree manipulations do often extend the current transaction but not
in all of the cases.  For example if we have only single block extents in
the tree, ocfs2_mark_extent_written() will end up calling
ocfs2_replace_extent_rec() all the time and we will never extend the
current transaction and eventually exhaust all the transaction credits if
the IO contains many single block extents.  Once that happens a
WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in
jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to
this error.  This was actually triggered by one of our customers on a
heavily fragmented OCFS2 filesystem.

To fix the issue make sure the transaction always has enough credits for
one extent insert before each call of ocfs2_mark_extent_written().

Heming Zhao said:

------
PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error"

PID: xxx  TASK: xxxx  CPU: 5  COMMAND: "SubmitThread-CA"
  #0 machine_kexec at ffffffff8c069932
  #1 __crash_kexec at ffffffff8c1338fa
  #2 panic at ffffffff8c1d69b9
  #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2]
  #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2]
  #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2]
  #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2]
  #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2]
  #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2]
  #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2]
#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2]
#11 dio_complete at ffffffff8c2b9fa7
#12 do_blockdev_direct_IO at ffffffff8c2bc09f
#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2]
#14 generic_file_direct_write at ffffffff8c1dcf14
#15 __generic_file_write_iter at ffffffff8c1dd07b
#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2]
#17 aio_write at ffffffff8c2cc72e
#18 kmem_cache_alloc at ffffffff8c248dde
#19 do_io_submit at ffffffff8c2ccada
#20 do_syscall_64 at ffffffff8c004984
#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
pelwell pushed a commit that referenced this issue Aug 2, 2024
[ Upstream commit 769e6a1 ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Athira Rajeev <[email protected]>
Cc: Ben Gainey <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kajol Jain <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: K Prateek Nayak <[email protected]>
Cc: Li Dong <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Oliver Upton <[email protected]>
Cc: Paran Lee <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ravi Bangoria <[email protected]>
Cc: Sun Haiyong <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: Yanteng Si <[email protected]>
Cc: Yicong Yang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Sep 2, 2024
A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <[email protected]>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>
ncopa pushed a commit to ncopa/linux that referenced this issue Sep 4, 2024
[ Upstream commit a699781 ]

A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  raspberrypi#8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  raspberrypi#9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 raspberrypi#10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 raspberrypi#11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 raspberrypi#12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 raspberrypi#13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 raspberrypi#14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 raspberrypi#15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 raspberrypi#16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 raspberrypi#17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <[email protected]>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Sep 6, 2024
[ Upstream commit a699781 ]

A sysfs reader can race with a device reset or removal, attempting to
read device state when the device is not actually present. eg:

     [exception RIP: qed_get_current_link+17]
  #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede]
  #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3
 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4
 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300
 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c
 #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b
 #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3
 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1
 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f
 #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb

 crash> struct net_device.state ffff9a9d21336000
    state = 5,

state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100).
The device is not present, note lack of __LINK_STATE_PRESENT (0b10).

This is the same sort of panic as observed in commit 4224cfd
("net-sysfs: add check for netdevice being present to speed_show").

There are many other callers of __ethtool_get_link_ksettings() which
don't have a device presence check.

Move this check into ethtool to protect all callers.

Fixes: d519e17 ("net: export device speed and duplex via sysfs")
Fixes: 4224cfd ("net-sysfs: add check for netdevice being present to speed_show")
Signed-off-by: Jamie Bainbridge <[email protected]>
Link: https://patch.msgid.link/8bae218864beaa44ed01628140475b9bf641c5b0.1724393671.git.jamie.bainbridge@gmail.com
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 4, 2024
[ Upstream commit 89a906d ]

Floating point instructions in userspace can crash some arm kernels
built with clang/LLD 17.0.6:

    BUG: unsupported FP instruction in kernel mode
    FPEXC == 0xc0000780
    Internal error: Oops - undefined instruction: 0 [#1] ARM
    CPU: 0 PID: 196 Comm: vfp-reproducer Not tainted 6.10.0 #1
    Hardware name: BCM2835
    PC is at vfp_support_entry+0xc8/0x2cc
    LR is at do_undefinstr+0xa8/0x250
    pc : [<c0101d50>]    lr : [<c010a80c>]    psr: a0000013
    sp : dc8d1f68  ip : 60000013  fp : bedea19c
    r10: ec532b17  r9 : 00000010  r8 : 0044766c
    r7 : c0000780  r6 : ec532b17  r5 : c1c13800  r4 : dc8d1fb0
    r3 : c10072c4  r2 : c0101c88  r1 : ec532b17  r0 : 0044766c
    Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
    Control: 00c5387d  Table: 0251c008  DAC: 00000051
    Register r0 information: non-paged memory
    Register r1 information: vmalloc memory
    Register r2 information: non-slab/vmalloc memory
    Register r3 information: non-slab/vmalloc memory
    Register r4 information: 2-page vmalloc region
    Register r5 information: slab kmalloc-cg-2k
    Register r6 information: vmalloc memory
    Register r7 information: non-slab/vmalloc memory
    Register r8 information: non-paged memory
    Register r9 information: zero-size pointer
    Register r10 information: vmalloc memory
    Register r11 information: non-paged memory
    Register r12 information: non-paged memory
    Process vfp-reproducer (pid: 196, stack limit = 0x61aaaf8b)
    Stack: (0xdc8d1f68 to 0xdc8d2000)
    1f60:                   0000081f b6f69300 0000000f c10073f4 c10072c4 dc8d1fb0
    1f80: ec532b17 0c532b17 0044766c b6f9ccd8 00000000 c010a80c 00447670 60000010
    1fa0: ffffffff c1c13800 00c5387d c0100f10 b6f68af8 00448fc0 00000000 bedea188
    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff 00000000 00000000
    Call trace:
    [<c0101d50>] (vfp_support_entry) from [<c010a80c>] (do_undefinstr+0xa8/0x250)
    [<c010a80c>] (do_undefinstr) from [<c0100f10>] (__und_usr+0x70/0x80)
    Exception stack(0xdc8d1fb0 to 0xdc8d1ff8)
    1fa0:                                     b6f68af8 00448fc0 00000000 bedea188
    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff
    Code: 0a000061 e3877202 e594003c e3a09010 (eef16a10)
    ---[ end trace 0000000000000000 ]---
    Kernel panic - not syncing: Fatal exception in interrupt
    ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

This is a minimal userspace reproducer on a Raspberry Pi Zero W:

    #include <stdio.h>
    #include <math.h>

    int main(void)
    {
            double v = 1.0;
            printf("%fn", NAN + *(volatile double *)&v);
            return 0;
    }

Another way to consistently trigger the oops is:

    calvin@raspberry-pi-zero-w ~$ python -c "import json"

The bug reproduces only when the kernel is built with DYNAMIC_DEBUG=n,
because the pr_debug() calls act as barriers even when not activated.

This is the output from the same kernel source built with the same
compiler and DYNAMIC_DEBUG=y, where the userspace reproducer works as
expected:

    VFP: bounce: trigger ec532b17 fpexc c0000780
    VFP: emulate: INST=0xee377b06 SCR=0x00000000
    VFP: bounce: trigger eef1fa10 fpexc c0000780
    VFP: emulate: INST=0xeeb40b40 SCR=0x00000000
    VFP: raising exceptions 30000000

    calvin@raspberry-pi-zero-w ~$ ./vfp-reproducer
    nan

Crudely grepping for vmsr/vmrs instructions in the otherwise nearly
idential text for vfp_support_entry() makes the problem obvious:

    vmlinux.llvm.good [0xc0101cb8] <+48>:  vmrs   r7, fpexc
    vmlinux.llvm.good [0xc0101cd8] <+80>:  vmsr   fpexc, r0
    vmlinux.llvm.good [0xc0101d20] <+152>: vmsr   fpexc, r7
    vmlinux.llvm.good [0xc0101d38] <+176>: vmrs   r4, fpexc
    vmlinux.llvm.good [0xc0101d6c] <+228>: vmrs   r0, fpscr
    vmlinux.llvm.good [0xc0101dc4] <+316>: vmsr   fpexc, r0
    vmlinux.llvm.good [0xc0101dc8] <+320>: vmrs   r0, fpsid
    vmlinux.llvm.good [0xc0101dcc] <+324>: vmrs   r6, fpscr
    vmlinux.llvm.good [0xc0101e10] <+392>: vmrs   r10, fpinst
    vmlinux.llvm.good [0xc0101eb8] <+560>: vmrs   r10, fpinst2

    vmlinux.llvm.bad  [0xc0101cb8] <+48>:  vmrs   r7, fpexc
    vmlinux.llvm.bad  [0xc0101cd8] <+80>:  vmsr   fpexc, r0
    vmlinux.llvm.bad  [0xc0101d20] <+152>: vmsr   fpexc, r7
    vmlinux.llvm.bad  [0xc0101d30] <+168>: vmrs   r0, fpscr
    vmlinux.llvm.bad  [0xc0101d50] <+200>: vmrs   r6, fpscr  <== BOOM!
    vmlinux.llvm.bad  [0xc0101d6c] <+228>: vmsr   fpexc, r0
    vmlinux.llvm.bad  [0xc0101d70] <+232>: vmrs   r0, fpsid
    vmlinux.llvm.bad  [0xc0101da4] <+284>: vmrs   r10, fpinst
    vmlinux.llvm.bad  [0xc0101df8] <+368>: vmrs   r4, fpexc
    vmlinux.llvm.bad  [0xc0101e5c] <+468>: vmrs   r10, fpinst2

I think LLVM's reordering is valid as the code is currently written: the
compiler doesn't know the instructions have side effects in hardware.

Fix by using "asm volatile" in fmxr() and fmrx(), so they cannot be
reordered with respect to each other. The original compiler now produces
working kernels on my hardware with DYNAMIC_DEBUG=n.

This is the relevant piece of the diff of the vfp_support_entry() text,
from the original oopsing kernel to a working kernel with this patch:

         vmrs r0, fpscr
         tst r0, #4096
         bne 0xc0101d48
         tst r0, #458752
         beq 0xc0101ecc
         orr r7, r7, #536870912
         ldr r0, [r4, #0x3c]
         mov r9, #16
        -vmrs r6, fpscr
         orr r9, r9, #251658240
         add r0, r0, #4
         str r0, [r4, #0x3c]
         mvn r0, #159
         sub r0, r0, #-1207959552
         and r0, r7, r0
         vmsr fpexc, r0
         vmrs r0, fpsid
        +vmrs r6, fpscr
         and r0, r0, #983040
         cmp r0, #65536
         bne 0xc0101d88

Fixes: 4708fb0 ("ARM: vfp: Reimplement VFP exception entry in C code")
Signed-off-by: Calvin Owens <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 10, 2024
[ Upstream commit 89a906d ]

Floating point instructions in userspace can crash some arm kernels
built with clang/LLD 17.0.6:

    BUG: unsupported FP instruction in kernel mode
    FPEXC == 0xc0000780
    Internal error: Oops - undefined instruction: 0 [#1] ARM
    CPU: 0 PID: 196 Comm: vfp-reproducer Not tainted 6.10.0 #1
    Hardware name: BCM2835
    PC is at vfp_support_entry+0xc8/0x2cc
    LR is at do_undefinstr+0xa8/0x250
    pc : [<c0101d50>]    lr : [<c010a80c>]    psr: a0000013
    sp : dc8d1f68  ip : 60000013  fp : bedea19c
    r10: ec532b17  r9 : 00000010  r8 : 0044766c
    r7 : c0000780  r6 : ec532b17  r5 : c1c13800  r4 : dc8d1fb0
    r3 : c10072c4  r2 : c0101c88  r1 : ec532b17  r0 : 0044766c
    Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
    Control: 00c5387d  Table: 0251c008  DAC: 00000051
    Register r0 information: non-paged memory
    Register r1 information: vmalloc memory
    Register r2 information: non-slab/vmalloc memory
    Register r3 information: non-slab/vmalloc memory
    Register r4 information: 2-page vmalloc region
    Register r5 information: slab kmalloc-cg-2k
    Register r6 information: vmalloc memory
    Register r7 information: non-slab/vmalloc memory
    Register r8 information: non-paged memory
    Register r9 information: zero-size pointer
    Register r10 information: vmalloc memory
    Register r11 information: non-paged memory
    Register r12 information: non-paged memory
    Process vfp-reproducer (pid: 196, stack limit = 0x61aaaf8b)
    Stack: (0xdc8d1f68 to 0xdc8d2000)
    1f60:                   0000081f b6f69300 0000000f c10073f4 c10072c4 dc8d1fb0
    1f80: ec532b17 0c532b17 0044766c b6f9ccd8 00000000 c010a80c 00447670 60000010
    1fa0: ffffffff c1c13800 00c5387d c0100f10 b6f68af8 00448fc0 00000000 bedea188
    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff 00000000 00000000
    Call trace:
    [<c0101d50>] (vfp_support_entry) from [<c010a80c>] (do_undefinstr+0xa8/0x250)
    [<c010a80c>] (do_undefinstr) from [<c0100f10>] (__und_usr+0x70/0x80)
    Exception stack(0xdc8d1fb0 to 0xdc8d1ff8)
    1fa0:                                     b6f68af8 00448fc0 00000000 bedea188
    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff
    Code: 0a000061 e3877202 e594003c e3a09010 (eef16a10)
    ---[ end trace 0000000000000000 ]---
    Kernel panic - not syncing: Fatal exception in interrupt
    ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

This is a minimal userspace reproducer on a Raspberry Pi Zero W:

    #include <stdio.h>
    #include <math.h>

    int main(void)
    {
            double v = 1.0;
            printf("%fn", NAN + *(volatile double *)&v);
            return 0;
    }

Another way to consistently trigger the oops is:

    calvin@raspberry-pi-zero-w ~$ python -c "import json"

The bug reproduces only when the kernel is built with DYNAMIC_DEBUG=n,
because the pr_debug() calls act as barriers even when not activated.

This is the output from the same kernel source built with the same
compiler and DYNAMIC_DEBUG=y, where the userspace reproducer works as
expected:

    VFP: bounce: trigger ec532b17 fpexc c0000780
    VFP: emulate: INST=0xee377b06 SCR=0x00000000
    VFP: bounce: trigger eef1fa10 fpexc c0000780
    VFP: emulate: INST=0xeeb40b40 SCR=0x00000000
    VFP: raising exceptions 30000000

    calvin@raspberry-pi-zero-w ~$ ./vfp-reproducer
    nan

Crudely grepping for vmsr/vmrs instructions in the otherwise nearly
idential text for vfp_support_entry() makes the problem obvious:

    vmlinux.llvm.good [0xc0101cb8] <+48>:  vmrs   r7, fpexc
    vmlinux.llvm.good [0xc0101cd8] <+80>:  vmsr   fpexc, r0
    vmlinux.llvm.good [0xc0101d20] <+152>: vmsr   fpexc, r7
    vmlinux.llvm.good [0xc0101d38] <+176>: vmrs   r4, fpexc
    vmlinux.llvm.good [0xc0101d6c] <+228>: vmrs   r0, fpscr
    vmlinux.llvm.good [0xc0101dc4] <+316>: vmsr   fpexc, r0
    vmlinux.llvm.good [0xc0101dc8] <+320>: vmrs   r0, fpsid
    vmlinux.llvm.good [0xc0101dcc] <+324>: vmrs   r6, fpscr
    vmlinux.llvm.good [0xc0101e10] <+392>: vmrs   r10, fpinst
    vmlinux.llvm.good [0xc0101eb8] <+560>: vmrs   r10, fpinst2

    vmlinux.llvm.bad  [0xc0101cb8] <+48>:  vmrs   r7, fpexc
    vmlinux.llvm.bad  [0xc0101cd8] <+80>:  vmsr   fpexc, r0
    vmlinux.llvm.bad  [0xc0101d20] <+152>: vmsr   fpexc, r7
    vmlinux.llvm.bad  [0xc0101d30] <+168>: vmrs   r0, fpscr
    vmlinux.llvm.bad  [0xc0101d50] <+200>: vmrs   r6, fpscr  <== BOOM!
    vmlinux.llvm.bad  [0xc0101d6c] <+228>: vmsr   fpexc, r0
    vmlinux.llvm.bad  [0xc0101d70] <+232>: vmrs   r0, fpsid
    vmlinux.llvm.bad  [0xc0101da4] <+284>: vmrs   r10, fpinst
    vmlinux.llvm.bad  [0xc0101df8] <+368>: vmrs   r4, fpexc
    vmlinux.llvm.bad  [0xc0101e5c] <+468>: vmrs   r10, fpinst2

I think LLVM's reordering is valid as the code is currently written: the
compiler doesn't know the instructions have side effects in hardware.

Fix by using "asm volatile" in fmxr() and fmrx(), so they cannot be
reordered with respect to each other. The original compiler now produces
working kernels on my hardware with DYNAMIC_DEBUG=n.

This is the relevant piece of the diff of the vfp_support_entry() text,
from the original oopsing kernel to a working kernel with this patch:

         vmrs r0, fpscr
         tst r0, #4096
         bne 0xc0101d48
         tst r0, #458752
         beq 0xc0101ecc
         orr r7, r7, #536870912
         ldr r0, [r4, #0x3c]
         mov r9, #16
        -vmrs r6, fpscr
         orr r9, r9, #251658240
         add r0, r0, #4
         str r0, [r4, #0x3c]
         mvn r0, #159
         sub r0, r0, #-1207959552
         and r0, r7, r0
         vmsr fpexc, r0
         vmrs r0, fpsid
        +vmrs r6, fpscr
         and r0, r0, #983040
         cmp r0, #65536
         bne 0xc0101d88

Fixes: 4708fb0 ("ARM: vfp: Reimplement VFP exception entry in C code")
Signed-off-by: Calvin Owens <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 10, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  #6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  #7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  #8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  #9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  #10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  #11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  #12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  #13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  #14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  #15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  #16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  #17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 10, 2024
[ Upstream commit 89a906d ]

Floating point instructions in userspace can crash some arm kernels
built with clang/LLD 17.0.6:

    BUG: unsupported FP instruction in kernel mode
    FPEXC == 0xc0000780
    Internal error: Oops - undefined instruction: 0 [#1] ARM
    CPU: 0 PID: 196 Comm: vfp-reproducer Not tainted 6.10.0 #1
    Hardware name: BCM2835
    PC is at vfp_support_entry+0xc8/0x2cc
    LR is at do_undefinstr+0xa8/0x250
    pc : [<c0101d50>]    lr : [<c010a80c>]    psr: a0000013
    sp : dc8d1f68  ip : 60000013  fp : bedea19c
    r10: ec532b17  r9 : 00000010  r8 : 0044766c
    r7 : c0000780  r6 : ec532b17  r5 : c1c13800  r4 : dc8d1fb0
    r3 : c10072c4  r2 : c0101c88  r1 : ec532b17  r0 : 0044766c
    Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
    Control: 00c5387d  Table: 0251c008  DAC: 00000051
    Register r0 information: non-paged memory
    Register r1 information: vmalloc memory
    Register r2 information: non-slab/vmalloc memory
    Register r3 information: non-slab/vmalloc memory
    Register r4 information: 2-page vmalloc region
    Register r5 information: slab kmalloc-cg-2k
    Register r6 information: vmalloc memory
    Register r7 information: non-slab/vmalloc memory
    Register r8 information: non-paged memory
    Register r9 information: zero-size pointer
    Register r10 information: vmalloc memory
    Register r11 information: non-paged memory
    Register r12 information: non-paged memory
    Process vfp-reproducer (pid: 196, stack limit = 0x61aaaf8b)
    Stack: (0xdc8d1f68 to 0xdc8d2000)
    1f60:                   0000081f b6f69300 0000000f c10073f4 c10072c4 dc8d1fb0
    1f80: ec532b17 0c532b17 0044766c b6f9ccd8 00000000 c010a80c 00447670 60000010
    1fa0: ffffffff c1c13800 00c5387d c0100f10 b6f68af8 00448fc0 00000000 bedea188
    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff 00000000 00000000
    Call trace:
    [<c0101d50>] (vfp_support_entry) from [<c010a80c>] (do_undefinstr+0xa8/0x250)
    [<c010a80c>] (do_undefinstr) from [<c0100f10>] (__und_usr+0x70/0x80)
    Exception stack(0xdc8d1fb0 to 0xdc8d1ff8)
    1fa0:                                     b6f68af8 00448fc0 00000000 bedea188
    1fc0: bedea314 00000001 00448ebc b6f9d000 00447608 b6f9ccd8 00000000 bedea19c
    1fe0: bede9198 bedea188 b6e1061c 0044766c 60000010 ffffffff
    Code: 0a000061 e3877202 e594003c e3a09010 (eef16a10)
    ---[ end trace 0000000000000000 ]---
    Kernel panic - not syncing: Fatal exception in interrupt
    ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

This is a minimal userspace reproducer on a Raspberry Pi Zero W:

    #include <stdio.h>
    #include <math.h>

    int main(void)
    {
            double v = 1.0;
            printf("%fn", NAN + *(volatile double *)&v);
            return 0;
    }

Another way to consistently trigger the oops is:

    calvin@raspberry-pi-zero-w ~$ python -c "import json"

The bug reproduces only when the kernel is built with DYNAMIC_DEBUG=n,
because the pr_debug() calls act as barriers even when not activated.

This is the output from the same kernel source built with the same
compiler and DYNAMIC_DEBUG=y, where the userspace reproducer works as
expected:

    VFP: bounce: trigger ec532b17 fpexc c0000780
    VFP: emulate: INST=0xee377b06 SCR=0x00000000
    VFP: bounce: trigger eef1fa10 fpexc c0000780
    VFP: emulate: INST=0xeeb40b40 SCR=0x00000000
    VFP: raising exceptions 30000000

    calvin@raspberry-pi-zero-w ~$ ./vfp-reproducer
    nan

Crudely grepping for vmsr/vmrs instructions in the otherwise nearly
idential text for vfp_support_entry() makes the problem obvious:

    vmlinux.llvm.good [0xc0101cb8] <+48>:  vmrs   r7, fpexc
    vmlinux.llvm.good [0xc0101cd8] <+80>:  vmsr   fpexc, r0
    vmlinux.llvm.good [0xc0101d20] <+152>: vmsr   fpexc, r7
    vmlinux.llvm.good [0xc0101d38] <+176>: vmrs   r4, fpexc
    vmlinux.llvm.good [0xc0101d6c] <+228>: vmrs   r0, fpscr
    vmlinux.llvm.good [0xc0101dc4] <+316>: vmsr   fpexc, r0
    vmlinux.llvm.good [0xc0101dc8] <+320>: vmrs   r0, fpsid
    vmlinux.llvm.good [0xc0101dcc] <+324>: vmrs   r6, fpscr
    vmlinux.llvm.good [0xc0101e10] <+392>: vmrs   r10, fpinst
    vmlinux.llvm.good [0xc0101eb8] <+560>: vmrs   r10, fpinst2

    vmlinux.llvm.bad  [0xc0101cb8] <+48>:  vmrs   r7, fpexc
    vmlinux.llvm.bad  [0xc0101cd8] <+80>:  vmsr   fpexc, r0
    vmlinux.llvm.bad  [0xc0101d20] <+152>: vmsr   fpexc, r7
    vmlinux.llvm.bad  [0xc0101d30] <+168>: vmrs   r0, fpscr
    vmlinux.llvm.bad  [0xc0101d50] <+200>: vmrs   r6, fpscr  <== BOOM!
    vmlinux.llvm.bad  [0xc0101d6c] <+228>: vmsr   fpexc, r0
    vmlinux.llvm.bad  [0xc0101d70] <+232>: vmrs   r0, fpsid
    vmlinux.llvm.bad  [0xc0101da4] <+284>: vmrs   r10, fpinst
    vmlinux.llvm.bad  [0xc0101df8] <+368>: vmrs   r4, fpexc
    vmlinux.llvm.bad  [0xc0101e5c] <+468>: vmrs   r10, fpinst2

I think LLVM's reordering is valid as the code is currently written: the
compiler doesn't know the instructions have side effects in hardware.

Fix by using "asm volatile" in fmxr() and fmrx(), so they cannot be
reordered with respect to each other. The original compiler now produces
working kernels on my hardware with DYNAMIC_DEBUG=n.

This is the relevant piece of the diff of the vfp_support_entry() text,
from the original oopsing kernel to a working kernel with this patch:

         vmrs r0, fpscr
         tst r0, #4096
         bne 0xc0101d48
         tst r0, #458752
         beq 0xc0101ecc
         orr r7, r7, #536870912
         ldr r0, [r4, #0x3c]
         mov r9, #16
        -vmrs r6, fpscr
         orr r9, r9, #251658240
         add r0, r0, #4
         str r0, [r4, #0x3c]
         mvn r0, #159
         sub r0, r0, #-1207959552
         and r0, r7, r0
         vmsr fpexc, r0
         vmrs r0, fpsid
        +vmrs r6, fpscr
         and r0, r0, #983040
         cmp r0, #65536
         bne 0xc0101d88

Fixes: 4708fb0 ("ARM: vfp: Reimplement VFP exception entry in C code")
Signed-off-by: Calvin Owens <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 10, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  #6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  #7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  #8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  #9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  #10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  #11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  #12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  #13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  #14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  #15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  #16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  #17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 10, 2024
commit 9af2efe upstream.

The fields in the hist_entry are filled on-demand which means they only
have meaningful values when relevant sort keys are used.

So if neither of 'dso' nor 'sym' sort keys are used, the map/symbols in
the hist entry can be garbage.  So it shouldn't access it
unconditionally.

I got a segfault, when I wanted to see cgroup profiles.

  $ sudo perf record -a --all-cgroups --synth=cgroup true

  $ sudo perf report -s cgroup

  Program received signal SIGSEGV, Segmentation fault.
  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  48		return RC_CHK_ACCESS(map)->dso;
  (gdb) bt
  #0  0x00005555557a8d90 in map__dso (map=0x0) at util/map.h:48
  #1  0x00005555557aa39b in map__load (map=0x0) at util/map.c:344
  #2  0x00005555557aa592 in map__find_symbol (map=0x0, addr=140736115941088) at util/map.c:385
  #3  0x00005555557ef000 in hists__findnew_entry (hists=0x555556039d60, entry=0x7fffffffa4c0, al=0x7fffffffa8c0, sample_self=true)
      at util/hist.c:644
  #4  0x00005555557ef61c in __hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      block_info=0x0, sample=0x7fffffffaa90, sample_self=true, ops=0x0) at util/hist.c:761
  #5  0x00005555557ef71f in hists__add_entry (hists=0x555556039d60, al=0x7fffffffa8c0, sym_parent=0x0, bi=0x0, mi=0x0, ki=0x0,
      sample=0x7fffffffaa90, sample_self=true) at util/hist.c:779
  #6  0x00005555557f00fb in iter_add_single_normal_entry (iter=0x7fffffffa900, al=0x7fffffffa8c0) at util/hist.c:1015
  #7  0x00005555557f09a7 in hist_entry_iter__add (iter=0x7fffffffa900, al=0x7fffffffa8c0, max_stack_depth=127, arg=0x7fffffffbce0)
      at util/hist.c:1260
  #8  0x00005555555ba7ce in process_sample_event (tool=0x7fffffffbce0, event=0x7ffff7c14128, sample=0x7fffffffaa90, evsel=0x555556039ad0,
      machine=0x5555560388e8) at builtin-report.c:334
  #9  0x00005555557b30c8 in evlist__deliver_sample (evlist=0x555556039010, tool=0x7fffffffbce0, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, evsel=0x555556039ad0, machine=0x5555560388e8) at util/session.c:1232
  #10 0x00005555557b32bc in machines__deliver_event (machines=0x5555560388e8, evlist=0x555556039010, event=0x7ffff7c14128,
      sample=0x7fffffffaa90, tool=0x7fffffffbce0, file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1271
  #11 0x00005555557b3848 in perf_session__deliver_event (session=0x5555560386d0, event=0x7ffff7c14128, tool=0x7fffffffbce0,
      file_offset=110888, file_path=0x555556038ff0 "perf.data") at util/session.c:1354
  #12 0x00005555557affaf in ordered_events__deliver_event (oe=0x555556038e60, event=0x555556135aa0) at util/session.c:132
  #13 0x00005555557bb605 in do_flush (oe=0x555556038e60, show_progress=false) at util/ordered-events.c:245
  #14 0x00005555557bb95c in __ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND, timestamp=0) at util/ordered-events.c:324
  #15 0x00005555557bba46 in ordered_events__flush (oe=0x555556038e60, how=OE_FLUSH__ROUND) at util/ordered-events.c:342
  #16 0x00005555557b1b3b in perf_event__process_finished_round (tool=0x7fffffffbce0, event=0x7ffff7c15bb8, oe=0x555556038e60)
      at util/session.c:780
  #17 0x00005555557b3b27 in perf_session__process_user_event (session=0x5555560386d0, event=0x7ffff7c15bb8, file_offset=117688,
      file_path=0x555556038ff0 "perf.data") at util/session.c:1406

As you can see the entry->ms.map was NULL even if he->ms.map has a
value.  This is because 'sym' sort key is not given, so it cannot assume
whether he->ms.sym and entry->ms.sym is the same.  I only checked the
'sym' sort key here as it implies 'dso' behavior (so maps are the same).

Fixes: ac01c8c ("perf hist: Update hist symbol when updating maps")
Signed-off-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix pushed a commit that referenced this issue Oct 28, 2024
During the migration of Soundwire runtime stream allocation from
the Qualcomm Soundwire controller to SoC's soundcard drivers the sdm845
soundcard was forgotten.

At this point any playback attempt or audio daemon startup, for instance
on sdm845-db845c (Qualcomm RB3 board), will result in stream pointer
NULL dereference:

 Unable to handle kernel NULL pointer dereference at virtual
 address 0000000000000020
 Mem abort info:
   ESR = 0x0000000096000004
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x04: level 0 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000101ecf000
 [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
 Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
 Modules linked in: ...
 CPU: 5 UID: 0 PID: 1198 Comm: aplay
 Not tainted 6.12.0-rc2-qcomlt-arm64-00059-g9d78f315a362-dirty #18
 Hardware name: Thundercomm Dragonboard 845c (DT)
 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
 lr : sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
 sp : ffff80008a2035c0
 x29: ffff80008a2035c0 x28: ffff80008a203978 x27: 0000000000000000
 x26: 00000000000000c0 x25: 0000000000000000 x24: ffff1676025f4800
 x23: ffff167600ff1cb8 x22: ffff167600ff1c98 x21: 0000000000000003
 x20: ffff167607316000 x19: ffff167604e64e80 x18: 0000000000000000
 x17: 0000000000000000 x16: ffffcec265074160 x15: 0000000000000000
 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff167600ff1cec
 x5 : ffffcec22cfa2010 x4 : 0000000000000000 x3 : 0000000000000003
 x2 : ffff167613f836c0 x1 : 0000000000000000 x0 : ffff16761feb60b8
 Call trace:
  sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
  wsa881x_hw_params+0x68/0x80 [snd_soc_wsa881x]
  snd_soc_dai_hw_params+0x3c/0xa4
  __soc_pcm_hw_params+0x230/0x660
  dpcm_be_dai_hw_params+0x1d0/0x3f8
  dpcm_fe_dai_hw_params+0x98/0x268
  snd_pcm_hw_params+0x124/0x460
  snd_pcm_common_ioctl+0x998/0x16e8
  snd_pcm_ioctl+0x34/0x58
  __arm64_sys_ioctl+0xac/0xf8
  invoke_syscall+0x48/0x104
  el0_svc_common.constprop.0+0x40/0xe0
  do_el0_svc+0x1c/0x28
  el0_svc+0x34/0xe0
  el0t_64_sync_handler+0x120/0x12c
  el0t_64_sync+0x190/0x194
 Code: aa0403fb f9418400 9100e000 9400102f (f8420f22)
 ---[ end trace 0000000000000000 ]---

0000000000006108 <sdw_stream_add_slave>:
    6108:       d503233f        paciasp
    610c:       a9b97bfd        stp     x29, x30, [sp, #-112]!
    6110:       910003fd        mov     x29, sp
    6114:       a90153f3        stp     x19, x20, [sp, #16]
    6118:       a9025bf5        stp     x21, x22, [sp, #32]
    611c:       aa0103f6        mov     x22, x1
    6120:       2a0303f5        mov     w21, w3
    6124:       a90363f7        stp     x23, x24, [sp, #48]
    6128:       aa0003f8        mov     x24, x0
    612c:       aa0203f7        mov     x23, x2
    6130:       a9046bf9        stp     x25, x26, [sp, #64]
    6134:       aa0403f9        mov     x25, x4        <-- x4 copied to x25
    6138:       a90573fb        stp     x27, x28, [sp, #80]
    613c:       aa0403fb        mov     x27, x4
    6140:       f9418400        ldr     x0, [x0, #776]
    6144:       9100e000        add     x0, x0, #0x38
    6148:       94000000        bl      0 <mutex_lock>
    614c:       f8420f22        ldr     x2, [x25, #32]!  <-- offset 0x44
    ^^^
This is 0x6108 + offset 0x44 from the beginning of sdw_stream_add_slave()
where data abort happens.
wsa881x_hw_params() is called with stream = NULL and passes it further
in register x4 (5th argument) to sdw_stream_add_slave() without any checks.
Value from x4 is copied to x25 and finally it aborts on trying to load
a value from address in x25 plus offset 32 (in dec) which corresponds
to master_list member in struct sdw_stream_runtime:

struct sdw_stream_runtime {
        const char  *              name;	/*     0     8 */
        struct sdw_stream_params   params;	/*     8    12 */
        enum sdw_stream_state      state;	/*    20     4 */
        enum sdw_stream_type       type;	/*    24     4 */
        /* XXX 4 bytes hole, try to pack */
 here-> struct list_head           master_list;	/*    32    16 */
        int                        m_rt_count;	/*    48     4 */
        /* size: 56, cachelines: 1, members: 6 */
        /* sum members: 48, holes: 1, sum holes: 4 */
        /* padding: 4 */
        /* last cacheline: 56 bytes */

Fix this by adding required calls to qcom_snd_sdw_startup() and
sdw_release_stream() to startup and shutdown routines which restores
the previous correct behaviour when ->set_stream() method is called to
set a valid stream runtime pointer on playback startup.

Reproduced and then fix was tested on db845c RB3 board.

Reported-by: Dmitry Baryshkov <[email protected]>
Cc: [email protected]
Fixes: 15c7fab ("ASoC: qcom: Move Soundwire runtime stream alloc to soundcards")
Cc: Srinivas Kandagatla <[email protected]>
Cc: Dmitry Baryshkov <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Cc: Pierre-Louis Bossart <[email protected]>
Signed-off-by: Alexey Klimov <[email protected]>
Tested-by: Steev Klimaszewski <[email protected]> # Lenovo Yoga C630
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Srinivas Kandagatla <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
popcornmix pushed a commit that referenced this issue Nov 1, 2024
commit d0e806b upstream.

During the migration of Soundwire runtime stream allocation from
the Qualcomm Soundwire controller to SoC's soundcard drivers the sdm845
soundcard was forgotten.

At this point any playback attempt or audio daemon startup, for instance
on sdm845-db845c (Qualcomm RB3 board), will result in stream pointer
NULL dereference:

 Unable to handle kernel NULL pointer dereference at virtual
 address 0000000000000020
 Mem abort info:
   ESR = 0x0000000096000004
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
   FSC = 0x04: level 0 translation fault
 Data abort info:
   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000101ecf000
 [0000000000000020] pgd=0000000000000000, p4d=0000000000000000
 Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
 Modules linked in: ...
 CPU: 5 UID: 0 PID: 1198 Comm: aplay
 Not tainted 6.12.0-rc2-qcomlt-arm64-00059-g9d78f315a362-dirty #18
 Hardware name: Thundercomm Dragonboard 845c (DT)
 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
 pc : sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
 lr : sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
 sp : ffff80008a2035c0
 x29: ffff80008a2035c0 x28: ffff80008a203978 x27: 0000000000000000
 x26: 00000000000000c0 x25: 0000000000000000 x24: ffff1676025f4800
 x23: ffff167600ff1cb8 x22: ffff167600ff1c98 x21: 0000000000000003
 x20: ffff167607316000 x19: ffff167604e64e80 x18: 0000000000000000
 x17: 0000000000000000 x16: ffffcec265074160 x15: 0000000000000000
 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff167600ff1cec
 x5 : ffffcec22cfa2010 x4 : 0000000000000000 x3 : 0000000000000003
 x2 : ffff167613f836c0 x1 : 0000000000000000 x0 : ffff16761feb60b8
 Call trace:
  sdw_stream_add_slave+0x44/0x380 [soundwire_bus]
  wsa881x_hw_params+0x68/0x80 [snd_soc_wsa881x]
  snd_soc_dai_hw_params+0x3c/0xa4
  __soc_pcm_hw_params+0x230/0x660
  dpcm_be_dai_hw_params+0x1d0/0x3f8
  dpcm_fe_dai_hw_params+0x98/0x268
  snd_pcm_hw_params+0x124/0x460
  snd_pcm_common_ioctl+0x998/0x16e8
  snd_pcm_ioctl+0x34/0x58
  __arm64_sys_ioctl+0xac/0xf8
  invoke_syscall+0x48/0x104
  el0_svc_common.constprop.0+0x40/0xe0
  do_el0_svc+0x1c/0x28
  el0_svc+0x34/0xe0
  el0t_64_sync_handler+0x120/0x12c
  el0t_64_sync+0x190/0x194
 Code: aa0403fb f9418400 9100e000 9400102f (f8420f22)
 ---[ end trace 0000000000000000 ]---

0000000000006108 <sdw_stream_add_slave>:
    6108:       d503233f        paciasp
    610c:       a9b97bfd        stp     x29, x30, [sp, #-112]!
    6110:       910003fd        mov     x29, sp
    6114:       a90153f3        stp     x19, x20, [sp, #16]
    6118:       a9025bf5        stp     x21, x22, [sp, #32]
    611c:       aa0103f6        mov     x22, x1
    6120:       2a0303f5        mov     w21, w3
    6124:       a90363f7        stp     x23, x24, [sp, #48]
    6128:       aa0003f8        mov     x24, x0
    612c:       aa0203f7        mov     x23, x2
    6130:       a9046bf9        stp     x25, x26, [sp, #64]
    6134:       aa0403f9        mov     x25, x4        <-- x4 copied to x25
    6138:       a90573fb        stp     x27, x28, [sp, #80]
    613c:       aa0403fb        mov     x27, x4
    6140:       f9418400        ldr     x0, [x0, #776]
    6144:       9100e000        add     x0, x0, #0x38
    6148:       94000000        bl      0 <mutex_lock>
    614c:       f8420f22        ldr     x2, [x25, #32]!  <-- offset 0x44
    ^^^
This is 0x6108 + offset 0x44 from the beginning of sdw_stream_add_slave()
where data abort happens.
wsa881x_hw_params() is called with stream = NULL and passes it further
in register x4 (5th argument) to sdw_stream_add_slave() without any checks.
Value from x4 is copied to x25 and finally it aborts on trying to load
a value from address in x25 plus offset 32 (in dec) which corresponds
to master_list member in struct sdw_stream_runtime:

struct sdw_stream_runtime {
        const char  *              name;	/*     0     8 */
        struct sdw_stream_params   params;	/*     8    12 */
        enum sdw_stream_state      state;	/*    20     4 */
        enum sdw_stream_type       type;	/*    24     4 */
        /* XXX 4 bytes hole, try to pack */
 here-> struct list_head           master_list;	/*    32    16 */
        int                        m_rt_count;	/*    48     4 */
        /* size: 56, cachelines: 1, members: 6 */
        /* sum members: 48, holes: 1, sum holes: 4 */
        /* padding: 4 */
        /* last cacheline: 56 bytes */

Fix this by adding required calls to qcom_snd_sdw_startup() and
sdw_release_stream() to startup and shutdown routines which restores
the previous correct behaviour when ->set_stream() method is called to
set a valid stream runtime pointer on playback startup.

Reproduced and then fix was tested on db845c RB3 board.

Reported-by: Dmitry Baryshkov <[email protected]>
Cc: [email protected]
Fixes: 15c7fab ("ASoC: qcom: Move Soundwire runtime stream alloc to soundcards")
Cc: Srinivas Kandagatla <[email protected]>
Cc: Dmitry Baryshkov <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Cc: Pierre-Louis Bossart <[email protected]>
Signed-off-by: Alexey Klimov <[email protected]>
Tested-by: Steev Klimaszewski <[email protected]> # Lenovo Yoga C630
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Reviewed-by: Srinivas Kandagatla <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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