BUG: unable to handle kernel paging request in validate_mm

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 96d454cd Merge tag 'arm64-fixes' of git://git.kernel.org/p..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17ccdf49900000
kernel config: https://syzkaller.appspot.com/x/.config?x=978db74cb30aa994
dashboard link: https://syzkaller.appspot.com/bug?extid=6bcd74cd645896f7589c
compiler: gcc (GCC) 10.1.0-syz 20200507
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

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+6bcd74...@syzkaller.appspotmail.com

BUG: unable to handle page fault for address: fffffbfff2af75e1
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 21ffe5067 P4D 21ffe5067 PUD 21ffe4067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 31422 Comm: syz-executor.3 Not tainted 5.9.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:91 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:108 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:134 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:165 [inline]
RIP: 0010:check_memory_region_inline mm/kasan/generic.c:183 [inline]
RIP: 0010:check_memory_region+0xdb/0x180 mm/kasan/generic.c:192
Code: 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 48 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 <80> 38 00 74 f2 eb d4 41 bc 08 00 00 00 48 89 ea 45 29 dc 4d 8d 1c
RSP: 0018:ffffc900057e7920 EFLAGS: 00010086
RAX: fffffbfff2af75e1 RBX: fffffbfff2af75e2 RCX: ffffffff815a0dee
RDX: fffffbfff2af75e2 RSI: 0000000000000008 RDI: ffffffff957baf08
RBP: fffffbfff2af75e1 R08: 0000000000000000 R09: ffffffff957baf0f
R10: fffffbfff2af75e1 R11: 00000000001033b8 R12: 0000000000000000
R13: ffff888050516c32 R14: ffff888050516300 R15: 0000000000000000
FS: 00000000027f2940(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffbfff2af75e1 CR3: 000000020feb8000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read include/linux/instrumented.h:56 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
__lock_acquire+0xfbe/0x5640 kernel/locking/lockdep.c:4396
lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:5005
down_read+0x96/0x420 kernel/locking/rwsem.c:1492
anon_vma_lock_read include/linux/rmap.h:130 [inline]
validate_mm+0xd3/0x800 mm/mmap.c:402
mmap_region+0x10ce/0x1780 mm/mmap.c:1815
do_mmap+0xcf9/0x11d0 mm/mmap.c:1545
vm_mmap_pgoff+0x195/0x200 mm/util.c:506
ksys_mmap_pgoff+0xde/0x560 mm/mmap.c:1596
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d60a
Code: 89 f5 41 54 49 89 fc 55 53 74 35 49 63 e8 48 63 da 4d 89 f9 49 89 e8 4d 63 d6 48 89 da 4c 89 ee 4c 89 e7 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 4e 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 00
RSP: 002b:000000000169fac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045d60a
RDX: 0000000000000003 RSI: 0000000000021000 RDI: 0000000000000000
RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000020022 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000021000 R14: 0000000000020022 R15: 0000000000000000
Modules linked in:
CR2: fffffbfff2af75e1
---[ end trace 2ecd674403f84a33 ]---
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:91 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:108 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:134 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:165 [inline]
RIP: 0010:check_memory_region_inline mm/kasan/generic.c:183 [inline]
RIP: 0010:check_memory_region+0xdb/0x180 mm/kasan/generic.c:192
Code: 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 48 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 <80> 38 00 74 f2 eb d4 41 bc 08 00 00 00 48 89 ea 45 29 dc 4d 8d 1c
RSP: 0018:ffffc900057e7920 EFLAGS: 00010086
RAX: fffffbfff2af75e1 RBX: fffffbfff2af75e2 RCX: ffffffff815a0dee
RDX: fffffbfff2af75e2 RSI: 0000000000000008 RDI: ffffffff957baf08
RBP: fffffbfff2af75e1 R08: 0000000000000000 R09: ffffffff957baf0f
R10: fffffbfff2af75e1 R11: 00000000001033b8 R12: 0000000000000000
R13: ffff888050516c32 R14: ffff888050516300 R15: 0000000000000000
FS: 00000000027f2940(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffbfff2af75e1 CR3: 000000020feb8000 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.