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general protection fault in netdev_core_pick_tx

Status: closed as invalid on 2025/03/30 10:14
Subsystems: net
[Documentation on labels]
First crash: 172d, last: 172d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in netdev_core_pick_tx block 19 C inconclusive done 6 856d 1010d 0/29 auto-obsoleted due to no activity on 2023/08/16 20:53
upstream KASAN: slab-use-after-free Read in netdev_core_pick_tx block 19 1 657d 657d 0/29 auto-obsoleted due to no activity on 2024/02/01 19:31

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 1037 Comm: kworker/u4:7 Not tainted 6.14.0-rc4-syzkaller-00282-g1973160c90d7 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:netdev_core_pick_tx+0xe5/0x320 net/core/dev.c:4524
Code: 00 00 49 8d 5d 08 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 a9 83 5e f8 48 8b 1b 48 83 c3 30 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 8c 83 5e f8 48 89 2c 24 48 8b 1b
RSP: 0018:ffffc900025bec78 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff888035cba440
RDX: ffff888035cba440 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff888044416028 R08: ffffffff89ca769c R09: 1ffffffff28a9318
R10: dffffc0000000000 R11: fffffbfff28a9319 R12: dffffc0000000000
R13: ffff888044416000 R14: ffff888033d34c80 R15: 1ffff11008882c05
FS:  0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffce1fd0f8 CR3: 00000000444e2000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __dev_queue_xmit+0x8d9/0x3f50 net/core/dev.c:4609
 dev_queue_xmit include/linux/netdevice.h:3313 [inline]
 vlan_dev_hard_start_xmit+0x36c/0x5f0 net/8021q/vlan_dev.c:125
 __netdev_start_xmit include/linux/netdevice.h:5151 [inline]
 netdev_start_xmit include/linux/netdevice.h:5160 [inline]
 xmit_one net/core/dev.c:3800 [inline]
 dev_hard_start_xmit+0x27a/0x7d0 net/core/dev.c:3816
 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4649
 neigh_output include/net/neighbour.h:539 [inline]
 ip6_finish_output2+0x12bc/0x17c0 net/ipv6/ip6_output.c:141
 ip6_finish_output+0x41e/0x840 net/ipv6/ip6_output.c:226
 NF_HOOK+0x9e/0x430 include/linux/netfilter.h:314
 mld_sendpack+0x843/0xdb0 net/ipv6/mcast.c:1868
 ipv6_mc_dad_complete+0x88/0x490 net/ipv6/mcast.c:2293
 addrconf_dad_completed+0x712/0xcd0 net/ipv6/addrconf.c:4336
 addrconf_dad_work+0xdbc/0x16a0
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:netdev_core_pick_tx+0xe5/0x320 net/core/dev.c:4524
Code: 00 00 49 8d 5d 08 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 a9 83 5e f8 48 8b 1b 48 83 c3 30 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 74 08 48 89 df e8 8c 83 5e f8 48 89 2c 24 48 8b 1b
RSP: 0018:ffffc900025bec78 EFLAGS: 00010206
RAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff888035cba440
RDX: ffff888035cba440 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff888044416028 R08: ffffffff89ca769c R09: 1ffffffff28a9318
R10: dffffc0000000000 R11: fffffbfff28a9319 R12: dffffc0000000000
R13: ffff888044416000 R14: ffff888033d34c80 R15: 1ffff11008882c05
FS:  0000000000000000(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffce1fd0f8 CR3: 00000000444e2000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	49 8d 5d 08          	lea    0x8(%r13),%rbx
   6:	48 89 d8             	mov    %rbx,%rax
   9:	48 c1 e8 03          	shr    $0x3,%rax
   d:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  12:	74 08                	je     0x1c
  14:	48 89 df             	mov    %rbx,%rdi
  17:	e8 a9 83 5e f8       	call   0xf85e83c5
  1c:	48 8b 1b             	mov    (%rbx),%rbx
  1f:	48 83 c3 30          	add    $0x30,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 8c 83 5e f8       	call   0xf85e83c5
  39:	48 89 2c 24          	mov    %rbp,(%rsp)
  3d:	48 8b 1b             	mov    (%rbx),%rbx

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/03 07:09 upstream 1973160c90d7 c3901742 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in netdev_core_pick_tx
* Struck through repros no longer work on HEAD.