BUG: unable to handle kernel NULL pointer dereference in syscall_trace_enter

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 399849e4 Linux 4.19.131
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13ad3ccb100000
kernel config: https://syzkaller.appspot.com/x/.config?x=eada6d424d8bae1d
dashboard link: https://syzkaller.appspot.com/bug?extid=ead7a3b7525ca598b2ac
compiler: gcc (GCC) 10.1.0-syz 20200507

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+ead7a3...@syzkaller.appspotmail.com

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 9187 Comm: systemd-udevd Not tainted 4.19.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:syscall_trace_enter+0xdf/0xd60 arch/x86/entry/common.c:82
Code: 00 fc ff df 65 4c 8b 2c 25 40 ee 01 00 4c 89 ea 81 c5 03 00 00 40 48 c1 ea 03 80 3c 02 00 0f 85 fc 0a 00 00 4d 8b 6d 00 31 ff <45> 00 00 00 00 e6 40 44 89 f6 e8 72 26 69 00 45 85 f6 0f 85 e7 05
RSP: 0018:ffff88804f397e30 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88804f397f58 RCX: ffffffff810082ef
RDX: 1ffff110094b20a8 RSI: ffffffff810082f9 RDI: 0000000000000000
RBP: 00000000c000003e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 1ffff11009e72fca
R13: 0000000000000100 R14: 0000000000000000 R15: 0000000000000000
FS: 00007fb2ce0728c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000009b22d000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_syscall_64+0x486/0x620 arch/x86/entry/common.c:283
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fb2ccee56f0
Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d 19 30 2c 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe 9d 01 00 48 89 04 24
RSP: 002b:00007ffd9a11e7e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000557f80efdd50 RCX: 00007fb2ccee56f0
RDX: 00000000000001b6 RSI: 0000000000080000 RDI: 00007ffd9a11e940
RBP: 0000000000000008 R08: 0000000000000008 R09: 0000000000000001
R10: 0000000000080000 R11: 0000000000000246 R12: 00007fb2cda418c9
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
CR2: 0000000000000000
BUG: unable to handle kernel NULL pointer dereference at 000000000000006e
PGD 9fd37067 P4D 9fd37067 PUD a3994067 PMD 0
Oops: 0002 [#2] PREEMPT SMP KASAN
CPU: 0 PID: 17160 Comm: syz-executor.0 Tainted: G D 4.19.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:trace_hardirqs_on_thunk+0x16/0x1c
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 7d 6e 00 eb 64 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41
RSP: 0018:ffff888043477290 EFLAGS: 00010086
RAX: ffff888043477298 RBX: 0000000000000000 RCX: ffffffff8158cbd3
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888049eb0d54
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffed1015cc473a
R10: ffff8880ae6239d3 R11: ffffffff8ad1f01b R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f7527477700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000006e CR3: 000000009f370000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
Modules linked in:
CR2: 000000000000006e
---[ end trace c27a2503e59ed721 ]---
BUG: unable to handle kernel NULL pointer dereference at 000000000000006e
RIP: 0010:syscall_trace_enter+0xdf/0xd60 arch/x86/entry/common.c:82
PGD 9fd37067 P4D 9fd37067 PUD a3994067 PMD 0
Code: 00 fc ff df 65 4c 8b 2c 25 40 ee 01 00 4c 89 ea 81 c5 03 00 00 40 48 c1 ea 03 80 3c 02 00 0f 85 fc 0a 00 00 4d 8b 6d 00 31 ff <45> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Oops: 0002 [#3] PREEMPT SMP KASAN
RSP: 0018:ffff88804f397e30 EFLAGS: 00010246
CPU: 1 PID: 17150 Comm: syz-executor.0 Tainted: G D 4.19.131-syzkaller #0
RAX: dffffc0000000000 RBX: ffff88804f397f58 RCX: ffffffff810082ef
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RDX: 1ffff110094b20a8 RSI: ffffffff810082f9 RDI: 0000000000000000
RIP: 0010:trace_hardirqs_on_thunk+0x16/0x1c
RBP: 00000000c000003e R08: 0000000000000000 R09: 0000000000000000
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 7d 6e 00 eb 64 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41
R10: 0000000000000005 R11: 0000000000000000 R12: 1ffff11009e72fca
RSP: 0018:ffff888056e67f50 EFLAGS: 00010086
R13: 0000000000000100 R14: 0000000000000000 R15: 0000000000000000
RAX: ffff888093a60540 RBX: 0000000000000000 RCX: ffffffff81009b36
FS: 00007f7527477700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
RDX: 0000000000000000 RSI: ffffffff8740008d RDI: ffff888093a60548
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000006e CR3: 000000009f370000 CR4: 00000000001426f0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
R10: 0000000000000005 R11: 0000000000000007 R12: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000


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[syzbot]

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