syzbot


BUG: unable to handle kernel NULL pointer dereference in dev_queue_xmit_nit

Status: upstream: reported C repro on 2023/12/17 17:53
Bug presence: origin:downstream
[Documentation on labels]
Reported-by: syzbot+f12ebc85232014b522b7@syzkaller.appspotmail.com
First crash: 208d, last: 78d
Fix bisection the fix commit could be any of (bisect log):
  8ddf523a1542 Revert "ip6_tunnel: make sure to pull inner header in __ip6_tnl_rcv()"
  e9ab1fe686bd Revert "serial: 8250_exar: Set missing rs485_supported flag"
  fcfe0289203a Merge 5.15.149 into android13-5.15-lts
  5b4517f7074b Revert "serial: 8250_exar: Fill in rs485_supported"
  
Bug presence (3)
Date Name Commit Repro Result
2023/12/17 android13-5.15-lts (ToT) 05ef4ccb5774 C [report] BUG: unable to handle kernel NULL pointer dereference in dev_queue_xmit_nit
2023/12/17 lts (merge base) 2a910f4af54d C Didn't crash
2023/12/17 upstream (ToT) 0e389834672c C Didn't crash
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 KASAN: use-after-free Read in dev_queue_xmit_nit C error 90 524d 1725d 0/1 upstream: reported C repro on 2019/10/22 19:23
linux-4.14 KASAN: use-after-free Read in dev_queue_xmit_nit (2) syz error 18 711d 1502d 0/1 upstream: reported syz repro on 2020/06/02 08:57
Fix bisection attempts (5)
Created Duration User Patch Repo Result
2024/05/27 04:17 1h51m bisect fix android13-5.15-lts OK (4) job log
2024/04/25 15:47 1h44m bisect fix android13-5.15-lts OK (0) job log log
2024/03/25 12:28 34m bisect fix android13-5.15-lts OK (0) job log log
2024/02/24 09:38 33m bisect fix android13-5.15-lts OK (0) job log log
2024/01/18 00:40 1h03m bisect fix android13-5.15-lts OK (0) job log log

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 0 
P4D 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 287 Comm: sshd Not tainted 5.15.139-syzkaller-00529-g05ef4ccb5774 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0000:ffffc900009d76c0 EFLAGS: 00010246
RAX: 1ffff11023e1d251 RBX: 0000000000000000 RCX: ffff88811df84000
RDX: ffff88810a164780 RSI: ffff88811df84000 RDI: ffff88811f1d6c80
RBP: ffffc900009d7760 R08: ffffffff83e41457 R09: ffffed10214ea755
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88810a164780 R14: ffff88811f1d6d54 R15: ffff88810a164780
FS:  00007fc63e54c800(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000011db6b000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dev_queue_xmit_nit+0x9a4/0xa40 net/core/dev.c:2349
 xmit_one net/core/dev.c:3616 [inline]
 dev_hard_start_xmit+0x149/0x620 net/core/dev.c:3637
 __dev_queue_xmit+0x18b4/0x2e70 net/core/dev.c:4252
 dev_queue_xmit+0x17/0x20 net/core/dev.c:4285
 tipc_l2_send_msg+0x296/0x320 net/tipc/bearer.c:514
 tipc_bearer_xmit_skb+0x2b1/0x3b0 net/tipc/bearer.c:560
 tipc_disc_timeout+0x6fa/0x8b0 net/tipc/discover.c:338
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1427
 expire_timers kernel/time/timer.c:1472 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1743
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1756
 __do_softirq+0x26d/0x5bf kernel/softirq.c:565
 invoke_softirq kernel/softirq.c:425 [inline]
 __irq_exit_rcu+0x50/0xf0 kernel/softirq.c:648
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:660
 common_interrupt+0x59/0xd0 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x27/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0033:0x7fc63e624773
Code: 00 f3 a5 48 8d 74 24 88 48 b9 ff ff ff 7f fe ff ff ff 48 21 c8 48 89 44 24 88 41 ba 08 00 00 00 44 89 c7 b8 0e 00 00 00 0f 05 <45> 31 c0 3d 00 f0 ff ff 76 06 41 89 c0 41 f7 d8 44 89 c0 5a c3 41
RSP: 002b:00007ffd7d7629f0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fc63e624773
RDX: 00007ffd7d762ad8 RSI: 00007ffd7d762a58 RDI: 0000000000000000
RBP: 00005615541ef5e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 000056155323eaa4
R13: 0000000000000016 R14: 000056155323f3e8 R15: 00007ffd7d762a58
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace df2f22ee8c63e4d6 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0000:ffffc900009d76c0 EFLAGS: 00010246
RAX: 1ffff11023e1d251 RBX: 0000000000000000 RCX: ffff88811df84000
RDX: ffff88810a164780 RSI: ffff88811df84000 RDI: ffff88811f1d6c80
RBP: ffffc900009d7760 R08: ffffffff83e41457 R09: ffffed10214ea755
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88810a164780 R14: ffff88811f1d6d54 R15: ffff88810a164780
FS:  00007fc63e54c800(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 000000011db6b000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/17 17:51 android13-5.15-lts 05ef4ccb5774 3222d10c .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: unable to handle kernel NULL pointer dereference in dev_queue_xmit_nit
* Struck through repros no longer work on HEAD.