Transmitting data on one I2C bus causes garbage to appear on second I2C bus #243
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I'd like to try this but that link is broken. Can you fix it? |
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Closing issue since there has been no activity for more than 2 months. Reopen if needed. |
popcornmix
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Dec 12, 2017
…l calls Provide a different lockdep key for rxrpc_call::user_mutex when the call is made on a kernel socket, such as by the AFS filesystem. The problem is that lockdep registers a false positive between userspace calling the sendmsg syscall on a user socket where call->user_mutex is held whilst userspace memory is accessed whereas the AFS filesystem may perform operations with mmap_sem held by the caller. In such a case, the following warning is produced. ====================================================== WARNING: possible circular locking dependency detected 4.14.0-fscache+ #243 Tainted: G E ------------------------------------------------------ modpost/16701 is trying to acquire lock: (&vnode->io_lock){+.+.}, at: [<ffffffffa000fc40>] afs_begin_vnode_operation+0x33/0x77 [kafs] but task is already holding lock: (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_sem){++++}: __might_fault+0x61/0x89 _copy_from_iter_full+0x40/0x1fa rxrpc_send_data+0x8dc/0xff3 rxrpc_do_sendmsg+0x62f/0x6a1 rxrpc_sendmsg+0x166/0x1b7 sock_sendmsg+0x2d/0x39 ___sys_sendmsg+0x1ad/0x22b __sys_sendmsg+0x41/0x62 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #2 (&call->user_mutex){+.+.}: __mutex_lock+0x86/0x7d2 rxrpc_new_client_call+0x378/0x80e rxrpc_kernel_begin_call+0xf3/0x154 afs_make_call+0x195/0x454 [kafs] afs_vl_get_capabilities+0x193/0x198 [kafs] afs_vl_lookup_vldb+0x5f/0x151 [kafs] afs_create_volume+0x2e/0x2f4 [kafs] afs_mount+0x56a/0x8d7 [kafs] mount_fs+0x6a/0x109 vfs_kern_mount+0x67/0x135 do_mount+0x90b/0xb57 SyS_mount+0x72/0x98 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #1 (k-sk_lock-AF_RXRPC){+.+.}: lock_sock_nested+0x74/0x8a rxrpc_kernel_begin_call+0x8a/0x154 afs_make_call+0x195/0x454 [kafs] afs_fs_get_capabilities+0x17a/0x17f [kafs] afs_probe_fileserver+0xf7/0x2f0 [kafs] afs_select_fileserver+0x83f/0x903 [kafs] afs_fetch_status+0x89/0x11d [kafs] afs_iget+0x16f/0x4f8 [kafs] afs_mount+0x6c6/0x8d7 [kafs] mount_fs+0x6a/0x109 vfs_kern_mount+0x67/0x135 do_mount+0x90b/0xb57 SyS_mount+0x72/0x98 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #0 (&vnode->io_lock){+.+.}: lock_acquire+0x174/0x19f __mutex_lock+0x86/0x7d2 afs_begin_vnode_operation+0x33/0x77 [kafs] afs_fetch_data+0x80/0x12a [kafs] afs_readpages+0x314/0x405 [kafs] __do_page_cache_readahead+0x203/0x2ba filemap_fault+0x179/0x54d __do_fault+0x17/0x60 __handle_mm_fault+0x6d7/0x95c handle_mm_fault+0x24e/0x2a3 __do_page_fault+0x301/0x486 do_page_fault+0x236/0x259 page_fault+0x22/0x30 __clear_user+0x3d/0x60 padzero+0x1c/0x2b load_elf_binary+0x785/0xdc7 search_binary_handler+0x81/0x1ff do_execveat_common.isra.14+0x600/0x888 do_execve+0x1f/0x21 SyS_execve+0x28/0x2f do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 other info that might help us debug this: Chain exists of: &vnode->io_lock --> &call->user_mutex --> &mm->mmap_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(&call->user_mutex); lock(&mm->mmap_sem); lock(&vnode->io_lock); *** DEADLOCK *** 1 lock held by modpost/16701: #0: (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486 stack backtrace: CPU: 0 PID: 16701 Comm: modpost Tainted: G E 4.14.0-fscache+ #243 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Call Trace: dump_stack+0x67/0x8e print_circular_bug+0x341/0x34f check_prev_add+0x11f/0x5d4 ? add_lock_to_list.isra.12+0x8b/0x8b ? add_lock_to_list.isra.12+0x8b/0x8b ? __lock_acquire+0xf77/0x10b4 __lock_acquire+0xf77/0x10b4 lock_acquire+0x174/0x19f ? afs_begin_vnode_operation+0x33/0x77 [kafs] __mutex_lock+0x86/0x7d2 ? afs_begin_vnode_operation+0x33/0x77 [kafs] ? afs_begin_vnode_operation+0x33/0x77 [kafs] ? afs_begin_vnode_operation+0x33/0x77 [kafs] afs_begin_vnode_operation+0x33/0x77 [kafs] afs_fetch_data+0x80/0x12a [kafs] afs_readpages+0x314/0x405 [kafs] __do_page_cache_readahead+0x203/0x2ba ? filemap_fault+0x179/0x54d filemap_fault+0x179/0x54d __do_fault+0x17/0x60 __handle_mm_fault+0x6d7/0x95c handle_mm_fault+0x24e/0x2a3 __do_page_fault+0x301/0x486 do_page_fault+0x236/0x259 page_fault+0x22/0x30 RIP: 0010:__clear_user+0x3d/0x60 RSP: 0018:ffff880071e93da0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000011c RCX: 000000000000011c RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000060f720 RBP: 000000000060f720 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff8800b5459b68 R12: ffff8800ce150e00 R13: 000000000060f720 R14: 00000000006127a8 R15: 0000000000000000 padzero+0x1c/0x2b load_elf_binary+0x785/0xdc7 search_binary_handler+0x81/0x1ff do_execveat_common.isra.14+0x600/0x888 do_execve+0x1f/0x21 SyS_execve+0x28/0x2f do_syscall_64+0x89/0x1be entry_SYSCALL64_slow_path+0x25/0x25 RIP: 0033:0x7fdb6009ee07 RSP: 002b:00007fff566d9728 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000055ba57280900 RCX: 00007fdb6009ee07 RDX: 000055ba5727f270 RSI: 000055ba5727cac0 RDI: 000055ba57280900 RBP: 000055ba57280900 R08: 00007fff566d9700 R09: 0000000000000000 R10: 000055ba5727cac0 R11: 0000000000000246 R12: 0000000000000000 R13: 000055ba5727cac0 R14: 000055ba5727f270 R15: 0000000000000000 Signed-off-by: David Howells <[email protected]>
popcornmix
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Feb 5, 2018
…l calls [ Upstream commit 9faaff5 ] Provide a different lockdep key for rxrpc_call::user_mutex when the call is made on a kernel socket, such as by the AFS filesystem. The problem is that lockdep registers a false positive between userspace calling the sendmsg syscall on a user socket where call->user_mutex is held whilst userspace memory is accessed whereas the AFS filesystem may perform operations with mmap_sem held by the caller. In such a case, the following warning is produced. ====================================================== WARNING: possible circular locking dependency detected 4.14.0-fscache+ #243 Tainted: G E ------------------------------------------------------ modpost/16701 is trying to acquire lock: (&vnode->io_lock){+.+.}, at: [<ffffffffa000fc40>] afs_begin_vnode_operation+0x33/0x77 [kafs] but task is already holding lock: (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_sem){++++}: __might_fault+0x61/0x89 _copy_from_iter_full+0x40/0x1fa rxrpc_send_data+0x8dc/0xff3 rxrpc_do_sendmsg+0x62f/0x6a1 rxrpc_sendmsg+0x166/0x1b7 sock_sendmsg+0x2d/0x39 ___sys_sendmsg+0x1ad/0x22b __sys_sendmsg+0x41/0x62 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #2 (&call->user_mutex){+.+.}: __mutex_lock+0x86/0x7d2 rxrpc_new_client_call+0x378/0x80e rxrpc_kernel_begin_call+0xf3/0x154 afs_make_call+0x195/0x454 [kafs] afs_vl_get_capabilities+0x193/0x198 [kafs] afs_vl_lookup_vldb+0x5f/0x151 [kafs] afs_create_volume+0x2e/0x2f4 [kafs] afs_mount+0x56a/0x8d7 [kafs] mount_fs+0x6a/0x109 vfs_kern_mount+0x67/0x135 do_mount+0x90b/0xb57 SyS_mount+0x72/0x98 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #1 (k-sk_lock-AF_RXRPC){+.+.}: lock_sock_nested+0x74/0x8a rxrpc_kernel_begin_call+0x8a/0x154 afs_make_call+0x195/0x454 [kafs] afs_fs_get_capabilities+0x17a/0x17f [kafs] afs_probe_fileserver+0xf7/0x2f0 [kafs] afs_select_fileserver+0x83f/0x903 [kafs] afs_fetch_status+0x89/0x11d [kafs] afs_iget+0x16f/0x4f8 [kafs] afs_mount+0x6c6/0x8d7 [kafs] mount_fs+0x6a/0x109 vfs_kern_mount+0x67/0x135 do_mount+0x90b/0xb57 SyS_mount+0x72/0x98 do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 -> #0 (&vnode->io_lock){+.+.}: lock_acquire+0x174/0x19f __mutex_lock+0x86/0x7d2 afs_begin_vnode_operation+0x33/0x77 [kafs] afs_fetch_data+0x80/0x12a [kafs] afs_readpages+0x314/0x405 [kafs] __do_page_cache_readahead+0x203/0x2ba filemap_fault+0x179/0x54d __do_fault+0x17/0x60 __handle_mm_fault+0x6d7/0x95c handle_mm_fault+0x24e/0x2a3 __do_page_fault+0x301/0x486 do_page_fault+0x236/0x259 page_fault+0x22/0x30 __clear_user+0x3d/0x60 padzero+0x1c/0x2b load_elf_binary+0x785/0xdc7 search_binary_handler+0x81/0x1ff do_execveat_common.isra.14+0x600/0x888 do_execve+0x1f/0x21 SyS_execve+0x28/0x2f do_syscall_64+0x89/0x1be return_from_SYSCALL_64+0x0/0x75 other info that might help us debug this: Chain exists of: &vnode->io_lock --> &call->user_mutex --> &mm->mmap_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(&call->user_mutex); lock(&mm->mmap_sem); lock(&vnode->io_lock); *** DEADLOCK *** 1 lock held by modpost/16701: #0: (&mm->mmap_sem){++++}, at: [<ffffffff8104376a>] __do_page_fault+0x1ef/0x486 stack backtrace: CPU: 0 PID: 16701 Comm: modpost Tainted: G E 4.14.0-fscache+ #243 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Call Trace: dump_stack+0x67/0x8e print_circular_bug+0x341/0x34f check_prev_add+0x11f/0x5d4 ? add_lock_to_list.isra.12+0x8b/0x8b ? add_lock_to_list.isra.12+0x8b/0x8b ? __lock_acquire+0xf77/0x10b4 __lock_acquire+0xf77/0x10b4 lock_acquire+0x174/0x19f ? afs_begin_vnode_operation+0x33/0x77 [kafs] __mutex_lock+0x86/0x7d2 ? afs_begin_vnode_operation+0x33/0x77 [kafs] ? afs_begin_vnode_operation+0x33/0x77 [kafs] ? afs_begin_vnode_operation+0x33/0x77 [kafs] afs_begin_vnode_operation+0x33/0x77 [kafs] afs_fetch_data+0x80/0x12a [kafs] afs_readpages+0x314/0x405 [kafs] __do_page_cache_readahead+0x203/0x2ba ? filemap_fault+0x179/0x54d filemap_fault+0x179/0x54d __do_fault+0x17/0x60 __handle_mm_fault+0x6d7/0x95c handle_mm_fault+0x24e/0x2a3 __do_page_fault+0x301/0x486 do_page_fault+0x236/0x259 page_fault+0x22/0x30 RIP: 0010:__clear_user+0x3d/0x60 RSP: 0018:ffff880071e93da0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000011c RCX: 000000000000011c RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000060f720 RBP: 000000000060f720 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff8800b5459b68 R12: ffff8800ce150e00 R13: 000000000060f720 R14: 00000000006127a8 R15: 0000000000000000 padzero+0x1c/0x2b load_elf_binary+0x785/0xdc7 search_binary_handler+0x81/0x1ff do_execveat_common.isra.14+0x600/0x888 do_execve+0x1f/0x21 SyS_execve+0x28/0x2f do_syscall_64+0x89/0x1be entry_SYSCALL64_slow_path+0x25/0x25 RIP: 0033:0x7fdb6009ee07 RSP: 002b:00007fff566d9728 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000055ba57280900 RCX: 00007fdb6009ee07 RDX: 000055ba5727f270 RSI: 000055ba5727cac0 RDI: 000055ba57280900 RBP: 000055ba57280900 R08: 00007fff566d9700 R09: 0000000000000000 R10: 000055ba5727cac0 R11: 0000000000000246 R12: 0000000000000000 R13: 000055ba5727cac0 R14: 000055ba5727f270 R15: 0000000000000000 Signed-off-by: David Howells <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix
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Apr 3, 2018
The ipv4 nf_ct code currently skips the nf_conntrak_in() call for fragmented packets. As a results later matches/target can end up manipulating template ct entry instead of 'real' ones. Exploiting the above, syzbot found a way to trigger the following splat: WARNING: CPU: 1 PID: 4242 at net/netfilter/xt_cluster.c:55 xt_cluster_mt+0x6c1/0x840 net/netfilter/xt_cluster.c:127 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 4242 Comm: syzkaller027971 Not tainted 4.16.0-rc2+ #243 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 panic+0x1e4/0x41c kernel/panic.c:183 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x211/0x2d0 lib/bug.c:184 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/kernel/traps.c:247 [inline] do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x58/0x80 arch/x86/entry/entry_64.S:957 RIP: 0010:xt_cluster_hash net/netfilter/xt_cluster.c:55 [inline] RIP: 0010:xt_cluster_mt+0x6c1/0x840 net/netfilter/xt_cluster.c:127 RSP: 0018:ffff8801d2f6f2d0 EFLAGS: 00010293 RAX: ffff8801af700540 RBX: 0000000000000000 RCX: ffffffff84a2d1e1 RDX: 0000000000000000 RSI: ffff8801d2f6f478 RDI: ffff8801cafd336a RBP: ffff8801d2f6f2e8 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801b03b3d18 R13: ffff8801cafd3300 R14: dffffc0000000000 R15: ffff8801d2f6f478 ipt_do_table+0xa91/0x19b0 net/ipv4/netfilter/ip_tables.c:296 iptable_filter_hook+0x65/0x80 net/ipv4/netfilter/iptable_filter.c:41 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 nf_hook include/linux/netfilter.h:243 [inline] NF_HOOK include/linux/netfilter.h:286 [inline] raw_send_hdrinc.isra.17+0xf39/0x1880 net/ipv4/raw.c:432 raw_sendmsg+0x14cd/0x26b0 net/ipv4/raw.c:669 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xca/0x110 net/socket.c:639 SYSC_sendto+0x361/0x5c0 net/socket.c:1748 SyS_sendto+0x40/0x50 net/socket.c:1716 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441b49 RSP: 002b:00007ffff5ca8b18 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441b49 RDX: 0000000000000030 RSI: 0000000020ff7000 RDI: 0000000000000003 RBP: 00000000006cc018 R08: 000000002066354c R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000403470 R13: 0000000000403500 R14: 0000000000000000 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. Instead of adding checks for template ct on every target/match manipulating skb->_nfct, simply drop the template ct when skipping nf_conntrack_in(). Fixes: 7b4fdf7 ("netfilter: don't track fragmented packets") Reported-and-tested-by: [email protected] Signed-off-by: Paolo Abeni <[email protected]> Acked-by: Florian Westphal <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]>
nathanchance
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Apr 8, 2018
commit aebfa52 upstream. The ipv4 nf_ct code currently skips the nf_conntrak_in() call for fragmented packets. As a results later matches/target can end up manipulating template ct entry instead of 'real' ones. Exploiting the above, syzbot found a way to trigger the following splat: WARNING: CPU: 1 PID: 4242 at net/netfilter/xt_cluster.c:55 xt_cluster_mt+0x6c1/0x840 net/netfilter/xt_cluster.c:127 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 4242 Comm: syzkaller027971 Not tainted 4.16.0-rc2+ raspberrypi#243 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 panic+0x1e4/0x41c kernel/panic.c:183 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x211/0x2d0 lib/bug.c:184 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/kernel/traps.c:247 [inline] do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x58/0x80 arch/x86/entry/entry_64.S:957 RIP: 0010:xt_cluster_hash net/netfilter/xt_cluster.c:55 [inline] RIP: 0010:xt_cluster_mt+0x6c1/0x840 net/netfilter/xt_cluster.c:127 RSP: 0018:ffff8801d2f6f2d0 EFLAGS: 00010293 RAX: ffff8801af700540 RBX: 0000000000000000 RCX: ffffffff84a2d1e1 RDX: 0000000000000000 RSI: ffff8801d2f6f478 RDI: ffff8801cafd336a RBP: ffff8801d2f6f2e8 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801b03b3d18 R13: ffff8801cafd3300 R14: dffffc0000000000 R15: ffff8801d2f6f478 ipt_do_table+0xa91/0x19b0 net/ipv4/netfilter/ip_tables.c:296 iptable_filter_hook+0x65/0x80 net/ipv4/netfilter/iptable_filter.c:41 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 nf_hook include/linux/netfilter.h:243 [inline] NF_HOOK include/linux/netfilter.h:286 [inline] raw_send_hdrinc.isra.17+0xf39/0x1880 net/ipv4/raw.c:432 raw_sendmsg+0x14cd/0x26b0 net/ipv4/raw.c:669 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xca/0x110 net/socket.c:639 SYSC_sendto+0x361/0x5c0 net/socket.c:1748 SyS_sendto+0x40/0x50 net/socket.c:1716 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441b49 RSP: 002b:00007ffff5ca8b18 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441b49 RDX: 0000000000000030 RSI: 0000000020ff7000 RDI: 0000000000000003 RBP: 00000000006cc018 R08: 000000002066354c R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000403470 R13: 0000000000403500 R14: 0000000000000000 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. Instead of adding checks for template ct on every target/match manipulating skb->_nfct, simply drop the template ct when skipping nf_conntrack_in(). Fixes: 7b4fdf7 ("netfilter: don't track fragmented packets") Reported-and-tested-by: [email protected] Signed-off-by: Paolo Abeni <[email protected]> Acked-by: Florian Westphal <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
popcornmix
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this issue
Apr 9, 2018
commit aebfa52 upstream. The ipv4 nf_ct code currently skips the nf_conntrak_in() call for fragmented packets. As a results later matches/target can end up manipulating template ct entry instead of 'real' ones. Exploiting the above, syzbot found a way to trigger the following splat: WARNING: CPU: 1 PID: 4242 at net/netfilter/xt_cluster.c:55 xt_cluster_mt+0x6c1/0x840 net/netfilter/xt_cluster.c:127 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 4242 Comm: syzkaller027971 Not tainted 4.16.0-rc2+ #243 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x24d lib/dump_stack.c:53 panic+0x1e4/0x41c kernel/panic.c:183 __warn+0x1dc/0x200 kernel/panic.c:547 report_bug+0x211/0x2d0 lib/bug.c:184 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178 fixup_bug arch/x86/kernel/traps.c:247 [inline] do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315 invalid_op+0x58/0x80 arch/x86/entry/entry_64.S:957 RIP: 0010:xt_cluster_hash net/netfilter/xt_cluster.c:55 [inline] RIP: 0010:xt_cluster_mt+0x6c1/0x840 net/netfilter/xt_cluster.c:127 RSP: 0018:ffff8801d2f6f2d0 EFLAGS: 00010293 RAX: ffff8801af700540 RBX: 0000000000000000 RCX: ffffffff84a2d1e1 RDX: 0000000000000000 RSI: ffff8801d2f6f478 RDI: ffff8801cafd336a RBP: ffff8801d2f6f2e8 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801b03b3d18 R13: ffff8801cafd3300 R14: dffffc0000000000 R15: ffff8801d2f6f478 ipt_do_table+0xa91/0x19b0 net/ipv4/netfilter/ip_tables.c:296 iptable_filter_hook+0x65/0x80 net/ipv4/netfilter/iptable_filter.c:41 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 nf_hook include/linux/netfilter.h:243 [inline] NF_HOOK include/linux/netfilter.h:286 [inline] raw_send_hdrinc.isra.17+0xf39/0x1880 net/ipv4/raw.c:432 raw_sendmsg+0x14cd/0x26b0 net/ipv4/raw.c:669 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xca/0x110 net/socket.c:639 SYSC_sendto+0x361/0x5c0 net/socket.c:1748 SyS_sendto+0x40/0x50 net/socket.c:1716 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x441b49 RSP: 002b:00007ffff5ca8b18 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000441b49 RDX: 0000000000000030 RSI: 0000000020ff7000 RDI: 0000000000000003 RBP: 00000000006cc018 R08: 000000002066354c R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000403470 R13: 0000000000403500 R14: 0000000000000000 R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. Instead of adding checks for template ct on every target/match manipulating skb->_nfct, simply drop the template ct when skipping nf_conntrack_in(). Fixes: 7b4fdf7 ("netfilter: don't track fragmented packets") Reported-and-tested-by: [email protected] Signed-off-by: Paolo Abeni <[email protected]> Acked-by: Florian Westphal <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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Feb 4, 2019
In a previous commit we switched from a d_alloc_name() + d_lookup() combination to setup a new dentry and find potential duplicates to the more idiomatic lookup_one_len(). As far as I understand, this also means we need to switch from d_add() to d_instantiate() since lookup_one_len() will create a new dentry when it doesn't find an existing one and add the new dentry to the hash queues. So we only need to call d_instantiate() to connect the dentry to the inode and turn it into a positive dentry. If we were to use d_add() we sure see stack traces like the following indicating that adding the same dentry twice over the same inode: [ 744.441889] CPU: 4 PID: 2849 Comm: landscape-sysin Not tainted 5.0.0-rc1-brauner-binderfs #243 [ 744.441889] Hardware name: Dell DCS XS24-SC2 /XS24-SC2 , BIOS S59_3C20 04/07/2011 [ 744.441889] RIP: 0010:__d_lookup_rcu+0x76/0x190 [ 744.441889] Code: 89 75 c0 49 c1 e9 20 49 89 fd 45 89 ce 41 83 e6 07 42 8d 04 f5 00 00 00 00 89 45 c8 eb 0c 48 8b 1b 48 85 db 0f 84 81 00 00 00 <44> 8b 63 fc 4c 3b 6b 10 75 ea 48 83 7b 08 00 74 e3 41 83 e4 fe 41 [ 744.441889] RSP: 0018:ffffb8c984e27ad0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 [ 744.441889] RAX: 0000000000000038 RBX: ffff9407ef770c08 RCX: ffffb8c980011000 [ 744.441889] RDX: ffffb8c984e27b54 RSI: ffffb8c984e27ce0 RDI: ffff9407e6689600 [ 744.441889] RBP: ffffb8c984e27b28 R08: ffffb8c984e27ba4 R09: 0000000000000007 [ 744.441889] R10: ffff9407e5c4f05c R11: 973f3eb9d84a94e5 R12: 0000000000000002 [ 744.441889] R13: ffff9407e6689600 R14: 0000000000000007 R15: 00000007bfef7a13 [ 744.441889] FS: 00007f0db13bb740(0000) GS:ffff9407f3b00000(0000) knlGS:0000000000000000 [ 744.441889] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 744.441889] CR2: 00007f0dacc51024 CR3: 000000032961a000 CR4: 00000000000006e0 [ 744.441889] Call Trace: [ 744.441889] lookup_fast+0x53/0x300 [ 744.441889] walk_component+0x49/0x350 [ 744.441889] ? inode_permission+0x63/0x1a0 [ 744.441889] link_path_walk.part.33+0x1bc/0x5a0 [ 744.441889] ? path_init+0x190/0x310 [ 744.441889] path_lookupat+0x95/0x210 [ 744.441889] filename_lookup+0xb6/0x190 [ 744.441889] ? __check_object_size+0xb8/0x1b0 [ 744.441889] ? strncpy_from_user+0x50/0x1a0 [ 744.441889] user_path_at_empty+0x36/0x40 [ 744.441889] ? user_path_at_empty+0x36/0x40 [ 744.441889] vfs_statx+0x76/0xe0 [ 744.441889] __do_sys_newstat+0x3d/0x70 [ 744.441889] __x64_sys_newstat+0x16/0x20 [ 744.441889] do_syscall_64+0x5a/0x120 [ 744.441889] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 744.441889] RIP: 0033:0x7f0db0ec2775 [ 744.441889] Code: 00 00 00 75 05 48 83 c4 18 c3 e8 26 55 02 00 66 0f 1f 44 00 00 83 ff 01 48 89 f0 77 30 48 89 c7 48 89 d6 b8 04 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 03 f3 c3 90 48 8b 15 e1 b6 2d 00 f7 d8 64 89 [ 744.441889] RSP: 002b:00007ffc36bc9388 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 [ 744.441889] RAX: ffffffffffffffda RBX: 00007ffc36bc9300 RCX: 00007f0db0ec2775 [ 744.441889] RDX: 00007ffc36bc9400 RSI: 00007ffc36bc9400 RDI: 00007f0dad26f050 [ 744.441889] RBP: 0000000000c0bc60 R08: 0000000000000000 R09: 0000000000000001 [ 744.441889] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc36bc9400 [ 744.441889] R13: 0000000000000001 R14: 00000000ffffff9c R15: 0000000000c0bc60 Cc: Al Viro <[email protected]> Signed-off-by: Christian Brauner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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This is from a fresh raspbian install with the latest image.
Make sure the I2C module isn't blacklisted
modprobe i2c-dev
Compile and run this: http://shiranui.lt3m.com/i2cspam.c
like: ./i2cspam /dev/i2c-0
Then do i2cdetect -a -y 1
Random addresses will show as present on whichever I2C bus you're /not/ transmitting on. This also causes confusion and deadlocks when you try to transmit on both I2C buses at once.
I have probed around on the board with a scope and there does not seem to be any kind of noise appearing on the I2C bus external to the chip, so this is either a driver bug or a board layout issue that is way harder to detect.
This test works at the default baud rate, and it works even if nothing is connected to either I2C bus.
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