syzbot


general protection fault in arp_create

Status: upstream: reported on 2024/12/23 22:52
Reported-by: syzbot+a1f7695e8a0ba60b2e2d@syzkaller.appspotmail.com
First crash: 50d, last: 50d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in arp_create (2) net 1 75d 75d 0/28 closed as invalid on 2025/01/02 16:12
linux-5.15 general protection fault in arp_create 1 147d 147d 0/3 auto-obsoleted due to no activity on 2024/12/27 05:27
upstream general protection fault in arp_create net 3 208d 296d 0/28 auto-obsoleted due to no activity on 2024/10/17 18:02
upstream general protection fault in arp_create (3) net 2 4d11h 2d03h 0/28 upstream: reported on 2025/02/10 18:11

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc000000001b: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000d8-0x00000000000000df]
CPU: 0 PID: 7023 Comm: kworker/u4:9 Tainted: G        W          6.1.121-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: bat_events batadv_bla_periodic_work
RIP: 0010:arp_create+0x42/0x920 net/ipv4/arp.c:553
Code: 49 89 ce 89 54 24 3c 89 74 24 30 89 fb 49 bd 00 00 00 00 00 fc ff df e8 5c 8c 4a f8 49 8d be de 00 00 00 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 f0 05 00 00 45 0f b7 a6 de 00 00 00 49
RSP: 0018:ffffc90004daf9b0 EFLAGS: 00010207
RAX: 000000000000001b RBX: 0000000000000002 RCX: ffff88807fa0bb80
RDX: 0000000000000000 RSI: 0000000000000806 RDI: 00000000000000de
RBP: ffffc90004dafb30 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000002
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8691996000 CR3: 000000005a6da000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 batadv_bla_send_claim+0x163/0xe30 net/batman-adv/bridge_loop_avoidance.c:361
 batadv_bla_send_announce net/batman-adv/bridge_loop_avoidance.c:675 [inline]
 batadv_bla_periodic_work+0x5d8/0xae0 net/batman-adv/bridge_loop_avoidance.c:1481
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arp_create+0x42/0x920 net/ipv4/arp.c:553
Code: 49 89 ce 89 54 24 3c 89 74 24 30 89 fb 49 bd 00 00 00 00 00 fc ff df e8 5c 8c 4a f8 49 8d be de 00 00 00 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 f0 05 00 00 45 0f b7 a6 de 00 00 00 49
RSP: 0018:ffffc90004daf9b0 EFLAGS: 00010207
RAX: 000000000000001b RBX: 0000000000000002 RCX: ffff88807fa0bb80
RDX: 0000000000000000 RSI: 0000000000000806 RDI: 00000000000000de
RBP: ffffc90004dafb30 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000002
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c71b547950 CR3: 0000000018bc7000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	49 89 ce             	mov    %rcx,%r14
   3:	89 54 24 3c          	mov    %edx,0x3c(%rsp)
   7:	89 74 24 30          	mov    %esi,0x30(%rsp)
   b:	89 fb                	mov    %edi,%ebx
   d:	49 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%r13
  14:	fc ff df
  17:	e8 5c 8c 4a f8       	call   0xf84a8c78
  1c:	49 8d be de 00 00 00 	lea    0xde(%r14),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 f0 05 00 00    	jne    0x627
  37:	45 0f b7 a6 de 00 00 	movzwl 0xde(%r14),%r12d
  3e:	00
  3f:	49                   	rex.WB

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/23 22:52 linux-6.1.y 29f02ec58a94 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan general protection fault in arp_create
* Struck through repros no longer work on HEAD.