syzbot


general protection fault in dropmon_net_event

Status: auto-closed as invalid on 2022/04/24 10:34
Reported-by: syzbot+1748c3a6354247cbbd9d@syzkaller.appspotmail.com
First crash: 1074d, last: 1074d

Sample crash report:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 853 Comm: kworker/u4:3 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:dropmon_net_event+0xd1/0x470 net/core/drop_monitor.c:341
Code: 00 00 e8 b2 02 df fa 49 bc 00 00 00 00 00 fc ff df 44 8b 35 d1 0c 54 07 eb 36 e8 9a 02 df fa 4c 8d 7b 10 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 d7 02 00 00 48 8b 43 10 48 89 dd 48 83 e8 10
RSP: 0018:ffff8880b3dc7920 EFLAGS: 00010a02
RAX: 1fe01ad80d18cd02 RBX: ff00d6c068c66800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff868382d6 RDI: 0000000000000001
RBP: ffff88800015f400 R08: 0000000000000000 R09: fffffbfff15c8ff4
R10: ffffffff8ae47fa7 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880952e0340 R14: 0000000000000001 R15: ff00d6c068c66810
FS:  0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c02cead000 CR3: 000000003f3f2000 CR4: 00000000003426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93
 call_netdevice_notifiers net/core/dev.c:1762 [inline]
 rollback_registered_many+0x83e/0xe70 net/core/dev.c:8196
 unregister_netdevice_many.part.0+0x1a/0x300 net/core/dev.c:9324
 unregister_netdevice_many+0x36/0x50 net/core/dev.c:9323
 sit_exit_batch_net+0x543/0x700 net/ipv6/sit.c:1893
 ops_exit_list+0xf9/0x150 net/core/net_namespace.c:156
 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:554
 process_one_work+0x864/0x1570 kernel/workqueue.c:2153
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace 8a1ef184a2ffeed4 ]---
RIP: 0010:dropmon_net_event+0xd1/0x470 net/core/drop_monitor.c:341
Code: 00 00 e8 b2 02 df fa 49 bc 00 00 00 00 00 fc ff df 44 8b 35 d1 0c 54 07 eb 36 e8 9a 02 df fa 4c 8d 7b 10 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 d7 02 00 00 48 8b 43 10 48 89 dd 48 83 e8 10
RSP: 0018:ffff8880b3dc7920 EFLAGS: 00010a02
RAX: 1fe01ad80d18cd02 RBX: ff00d6c068c66800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff868382d6 RDI: 0000000000000001
RBP: ffff88800015f400 R08: 0000000000000000 R09: fffffbfff15c8ff4
R10: ffffffff8ae47fa7 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880952e0340 R14: 0000000000000001 R15: ff00d6c068c66810
FS:  0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c02cead000 CR3: 000000003f3f2000 CR4: 00000000003426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	e8 b2 02 df fa       	callq  0xfadf02b9
   7:	49 bc 00 00 00 00 00 	movabs $0xdffffc0000000000,%r12
   e:	fc ff df
  11:	44 8b 35 d1 0c 54 07 	mov    0x7540cd1(%rip),%r14d        # 0x7540ce9
  18:	eb 36                	jmp    0x50
  1a:	e8 9a 02 df fa       	callq  0xfadf02b9
  1f:	4c 8d 7b 10          	lea    0x10(%rbx),%r15
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	0f 85 d7 02 00 00    	jne    0x30c
  35:	48 8b 43 10          	mov    0x10(%rbx),%rax
  39:	48 89 dd             	mov    %rbx,%rbp
  3c:	48 83 e8 10          	sub    $0x10,%rax

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/25 10:34 linux-4.19.y 3f8a27f9e27b 6caa12e4 .config console log report info ci2-linux-4-19 general protection fault in dropmon_net_event
* Struck through repros no longer work on HEAD.