BUG: stack guard page was hit in cmp_ex_search

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f4d51dff Linux 5.9-rc4
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1406fe59900000
kernel config: https://syzkaller.appspot.com/x/.config?x=a9075b36a6ae26c9
dashboard link: https://syzkaller.appspot.com/bug?extid=04580ec96df132228289
compiler: gcc (GCC) 10.1.0-syz 20200507
CC: [ak...@linux-foundation.org and...@fb.com a...@kernel.org b...@vger.kernel.org dan...@iogearbox.net john.fa...@gmail.com jo...@kernel.org ka...@fb.com kps...@chromium.org linux-...@vger.kernel.org natecha...@gmail.com net...@vger.kernel.org songliu...@fb.com y...@fb.com]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+04580e...@syzkaller.appspotmail.com

BUG: stack guard page was hit at 000000004bb8d970 (stack is 0000000036dee0a2..0000000023253a65)
kernel stack overflow (double-fault): 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 335 Comm: kworker/u4:6 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:cmp_ex_search+0x2/0xb0 lib/extable.c:96
Code: 41 f7 dc e8 20 32 c2 fd 44 89 e0 5b 5d 41 5c c3 48 89 df e8 00 38 02 fe eb b0 48 89 ef e8 f6 37 02 fe e9 76 ff ff ff 90 41 54 <55> 48 89 fd 53 48 89 f3 e8 f1 31 c2 fd 48 89 ea 48 b8 00 00 00 00
RSP: 0018:ffffc90002090000 EFLAGS: 00010082
RAX: 0000000000000000 RBX: fffff5200041200b RCX: ffffffff839a886f
RDX: ffffffff83b21b80 RSI: ffffffff89921cc4 RDI: ffffc90002090078
RBP: 00000000000004f6 R08: ffffffff83b21b80 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89921cc4
R13: 000000000000027b R14: ffffffff8991ff00 R15: ffffc90002090078
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc9000208fff8 CR3: 0000000093005000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__inline_bsearch include/linux/bsearch.h:15 [inline]
bsearch+0x57/0xb0 lib/bsearch.c:33
search_extable+0x7f/0xb0 lib/extable.c:120
search_kernel_exception_table kernel/extable.c:48 [inline]
search_exception_tables+0x33/0x50 kernel/extable.c:57
fixup_exception+0x4b/0xca arch/x86/mm/extable.c:161
no_context+0xe7/0x9f0 arch/x86/mm/fault.c:645
__bad_area_nosemaphore+0xa9/0x4f0 arch/x86/mm/fault.c:835
do_user_addr_fault+0x760/0xbf0 arch/x86/mm/fault.c:1248
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0xa8/0x190 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0010:preempt_schedule_notrace_thunk+0x5/0x31 arch/x86/entry/thunk_64.S:41
Code: 00 48 8d a0 58 ff ff ff e8 e9 04 46 00 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 b5 f5 06 eb 18 55 48 89 e5 57 <00> 00 00 00 41 50 41 51 41 52 41 53 e8 eb b5 f5 06 eb 00 41 5b 41
RSP: 0018:ffffc900020903d0 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff1308b21
RDX: dffffc0000000000 RSI: ffffffff89bd6980 RDI: 0000000000000082
RBP: ffffc900020903d8 R08: 0000000000000000 R09: ffffffff8ab26b8f
R10: fffffbfff1564d71 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
rcu_read_unlock_sched_notrace include/linux/rcupdate.h:772 [inline]
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3f0/0xae0 kernel/locking/lockdep.c:4980
rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
rcu_read_lock include/linux/rcupdate.h:634 [inline]
search_bpf_extables+0x3a/0x2e0 kernel/bpf/core.c:725
fixup_exception+0x4b/0xca arch/x86/mm/extable.c:161
no_context+0xe7/0x9f0 arch/x86/mm/fault.c:645
__bad_area_nosemaphore+0xa9/0x4f0 arch/x86/mm/fault.c:835
do_user_addr_fault+0x760/0xbf0 arch/x86/mm/fault.c:1248
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0xa8/0x190 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0010:preempt_schedule_notrace_thunk+0x5/0x31 arch/x86/entry/thunk_64.S:41
Code: 00 48 8d a0 58 ff ff ff e8 e9 04 46 00 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 b5 f5 06 eb 18 55 48 89 e5 57 <00> 00 00 00 41 50 41 51 41 52 41 53 e8 eb b5 f5 06 eb 00 41 5b 41
RSP: 0018:ffffc900020907f0 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff1308b21
RDX: dffffc0000000000 RSI: ffffffff89bd6980 RDI: 0000000000000082
RBP: ffffc900020907f8 R08: 0000000000000000 R09: ffffffff8ab26b8f
R10: fffffbfff1564d71 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
rcu_read_unlock_sched_notrace include/linux/rcupdate.h:772 [inline]
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3f0/0xae0 kernel/locking/lockdep.c:4980
rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
rcu_read_lock include/linux/rcupdate.h:634 [inline]
search_bpf_extables+0x3a/0x2e0 kernel/bpf/core.c:725
fixup_exception+0x4b/0xca arch/x86/mm/extable.c:161
no_context+0xe7/0x9f0 arch/x86/mm/fault.c:645
__bad_area_nosemaphore+0xa9/0x4f0 arch/x86/mm/fault.c:835
do_user_addr_fault+0x760/0xbf0 arch/x86/mm/fault.c:1248
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0xa8/0x190 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0010:preempt_schedule_notrace_thunk+0x5/0x31 arch/x86/entry/thunk_64.S:41
Code: 00 48 8d a0 58 ff ff ff e8 e9 04 46 00 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 b5 f5 06 eb 18 55 48 89 e5 57 <00> 00 00 00 41 50 41 51 41 52 41 53 e8 eb b5 f5 06 eb 00 41 5b 41
RSP: 0018:ffffc90002090c10 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff1308b21
RDX: dffffc0000000000 RSI: ffffffff89bd6980 RDI: 0000000000000082
RBP: ffffc90002090c18 R08: 0000000000000000 R09: ffffffff8ab26b8f
R10: fffffbfff1564d71 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
rcu_read_unlock_sched_notrace include/linux/rcupdate.h:772 [inline]
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3f0/0xae0 kernel/locking/lockdep.c:4980
rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
rcu_read_lock include/linux/rcupdate.h:634 [inline]
search_bpf_extables+0x3a/0x2e0 kernel/bpf/core.c:725
fixup_exception+0x4b/0xca arch/x86/mm/extable.c:161
no_context+0xe7/0x9f0 arch/x86/mm/fault.c:645
__bad_area_nosemaphore+0xa9/0x4f0 arch/x86/mm/fault.c:835
do_user_addr_fault+0x760/0xbf0 arch/x86/mm/fault.c:1248
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0xa8/0x190 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0010:preempt_schedule_notrace_thunk+0x5/0x31 arch/x86/entry/thunk_64.S:41
Code: 00 48 8d a0 58 ff ff ff e8 e9 04 46 00 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 b5 f5 06 eb 18 55 48 89 e5 57 <00> 00 00 00 41 50 41 51 41 52 41 53 e8 eb b5 f5 06 eb 00 41 5b 41
RSP: 0018:ffffc90002091030 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff1308b21
RDX: dffffc0000000000 RSI: ffffffff89bd6980 RDI: 0000000000000082
RBP: ffffc90002091038 R08: 0000000000000000 R09: ffffffff8ab26b8f
R10: fffffbfff1564d71 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
rcu_read_unlock_sched_notrace include/linux/rcupdate.h:772 [inline]
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3f0/0xae0 kernel/locking/lockdep.c:4980
rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
rcu_read_lock include/linux/rcupdate.h:634 [inline]
search_bpf_extables+0x3a/0x2e0 kernel/bpf/core.c:725
fixup_exception+0x4b/0xca arch/x86/mm/extable.c:161
no_context+0xe7/0x9f0 arch/x86/mm/fault.c:645
__bad_area_nosemaphore+0xa9/0x4f0 arch/x86/mm/fault.c:835
do_user_addr_fault+0x760/0xbf0 arch/x86/mm/fault.c:1248
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0xa8/0x190 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0010:preempt_schedule_notrace_thunk+0x5/0x31 arch/x86/entry/thunk_64.S:41
Code: 00 48 8d a0 58 ff ff ff e8 e9 04 46 00 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 b5 f5 06 eb 18 55 48 89 e5 57 <00> 00 00 00 41 50 41 51 41 52 41 53 e8 eb b5 f5 06 eb 00 41 5b 41
RSP: 0018:ffffc90002091450 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff1308b21
RDX: dffffc0000000000 RSI: ffffffff89bd6980 RDI: 0000000000000082
RBP: ffffc90002091458 R08: 0000000000000000 R09: ffffffff8ab26b8f
R10: fffffbfff1564d71 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
rcu_read_unlock_sched_notrace include/linux/rcupdate.h:772 [inline]
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3f0/0xae0 kernel/locking/lockdep.c:4980
rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
rcu_read_lock include/linux/rcupdate.h:634 [inline]
search_bpf_extables+0x3a/0x2e0 kernel/bpf/core.c:725
fixup_exception+0x4b/0xca arch/x86/mm/extable.c:161
no_context+0xe7/0x9f0 arch/x86/mm/fault.c:645
__bad_area_nosemaphore+0xa9/0x4f0 arch/x86/mm/fault.c:835
do_user_addr_fault+0x760/0xbf0 arch/x86/mm/fault.c:1248
handle_page_fault arch/x86/mm/fault.c:1429 [inline]
exc_page_fault+0xa8/0x190 arch/x86/mm/fault.c:1482
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:538
RIP: 0010:preempt_schedule_notrace_thunk+0x5/0x31 arch/x86/entry/thunk_64.S:41
Code: 00 48 8d a0 58 ff ff ff e8 e9 04 46 00 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 b5 f5 06 eb 18 55 48 89 e5 57 <00> 00 00 00 41 50 41 51 41 52 41 53 e8 eb b5 f5 06 eb 00 41 5b 41
RSP: 0018:ffffc90002091870 EFLAGS: 00010046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 1ffffffff1308b21
RDX: dffffc0000000000 RSI: ffffffff89bd6980 RDI: 0000000000000082
RBP: ffffc90002091878 R08
Lost 705 message(s)!
---[ end trace 9e6b1b6c2b87a920 ]---
RIP: 0010:cmp_ex_search+0x2/0xb0 lib/extable.c:96
Code: 41 f7 dc e8 20 32 c2 fd 44 89 e0 5b 5d 41 5c c3 48 89 df e8 00 38 02 fe eb b0 48 89 ef e8 f6 37 02 fe e9 76 ff ff ff 90 41 54 <55> 48 89 fd 53 48 89 f3 e8 f1 31 c2 fd 48 89 ea 48 b8 00 00 00 00
RSP: 0018:ffffc90002090000 EFLAGS: 00010082
RAX: 0000000000000000 RBX: fffff5200041200b RCX: ffffffff839a886f
RDX: ffffffff83b21b80 RSI: ffffffff89921cc4 RDI: ffffc90002090078
RBP: 00000000000004f6 R08: ffffffff83b21b80 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff89921cc4
R13: 000000000000027b R14: ffffffff8991ff00 R15: ffffc90002090078
FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc9000208fff8 CR3: 0000000093005000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.