general protection fault in __skb_try_recv_from_queue

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3dbdb38e2869 Merge branch 'for-5.14' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1538e772300000
kernel config: https://syzkaller.appspot.com/x/.config?x=a1fcf15a09815757
dashboard link: https://syzkaller.appspot.com/bug?extid=0fedf2c4893c8cf06c54
CC: [da...@davemloft.net edum...@google.com ktk...@virtuozzo.com ku...@kernel.org linux-...@vger.kernel.org mchehab...@kernel.org net...@vger.kernel.org wil...@google.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+0fedf2...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 4878 Comm: systemd-udevd Tainted: G W 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__skb_unlink include/linux/skbuff.h:2093 [inline]
RIP: 0010:__skb_try_recv_from_queue+0x663/0x820 net/core/datagram.c:199
Code: 8d 7d 08 49 8b 5c 24 08 48 b8 00 00 00 00 00 fc ff df 49 c7 44 24 08 00 00 00 00 48 89 fa 49 c7 04 24 00 00 00 00 48 c1 ea 03 <80> 3c 02 00 0f 85 f5 00 00 00 48 89 da 48 89 5d 08 48 b8 00 00 00
RSP: 0018:ffffc9000161f720 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: ffff88802ca801b0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff870ea98b RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffc9000161f8a0
R10: ffffffff870ea413 R11: 0000000000000000 R12: ffff888000101dc0
R13: ffff888032b5f3c0 R14: 0000000000000000 R15: 0000000000000293
FS: 00007f6a9a3068c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f04fe350000 CR3: 0000000017586000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__skb_try_recv_datagram+0x159/0x4e0 net/core/datagram.c:265
__skb_recv_datagram+0x1a1/0x220 net/core/datagram.c:297
skb_recv_datagram+0xa7/0xe0 net/core/datagram.c:317
netlink_recvmsg+0xe1/0xeb0 net/netlink/af_netlink.c:1952
sock_recvmsg_nosec net/socket.c:936 [inline]
sock_recvmsg net/socket.c:954 [inline]
sock_recvmsg net/socket.c:950 [inline]
____sys_recvmsg+0x2c4/0x600 net/socket.c:2604
___sys_recvmsg+0x127/0x200 net/socket.c:2646
__sys_recvmsg+0xe2/0x1a0 net/socket.c:2676
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f6a9944cdc7
Code: 89 01 b8 ff ff ff ff eb d8 66 2e 0f 1f 84 00 00 00 00 00 8b 05 0a b6 20 00 85 c0 75 2e 48 63 ff 48 63 d2 b8 2f 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 b1 71 20 00 f7 d8 64 89 02 48
RSP: 002b:00007ffdf650a398 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007ffdf650c5b0 RCX: 00007f6a9944cdc7
RDX: 0000000000000000 RSI: 00007ffdf650a430 RDI: 0000000000000003
RBP: 00007ffdf650c5a8 R08: 0000000000000008 R09: 000055a343c7e198
R10: 0000000000000004 R11: 0000000000000246 R12: 000055a343c7b930
R13: 000055a343c8d400 R14: 00007ffdf650a510 R15: 0000000000000001
Modules linked in:
---[ end trace ee85d48a1bb81f6c ]---
RIP: 0010:__skb_unlink include/linux/skbuff.h:2093 [inline]
RIP: 0010:__skb_try_recv_from_queue+0x663/0x820 net/core/datagram.c:199
Code: 8d 7d 08 49 8b 5c 24 08 48 b8 00 00 00 00 00 fc ff df 49 c7 44 24 08 00 00 00 00 48 89 fa 49 c7 04 24 00 00 00 00 48 c1 ea 03 <80> 3c 02 00 0f 85 f5 00 00 00 48 89 da 48 89 5d 08 48 b8 00 00 00
RSP: 0018:ffffc9000161f720 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: ffff88802ca801b0 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff870ea98b RDI: 0000000000000008
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffc9000161f8a0
R10: ffffffff870ea413 R11: 0000000000000000 R12: ffff888000101dc0
R13: ffff888032b5f3c0 R14: 0000000000000000 R15: 0000000000000293
FS: 00007f6a9a3068c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f04fe350000 CR3: 0000000017586000 CR4: 00000000001526f0
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.