syzbot


general protection fault in netlink_broadcast_filtered

Status: closed as invalid on 2025/07/02 15:51
Subsystems: net
[Documentation on labels]
First crash: 106d, last: 86d

Sample crash report:
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 0 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.15.0-rc6-syzkaller-00051-g405e6c37c89e #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: netns cleanup_net
RIP: 0010:read_pnet include/net/net_namespace.h:409 [inline]
RIP: 0010:sock_net include/net/sock.h:664 [inline]
RIP: 0010:netlink_broadcast_filtered+0x54/0x1140 net/netlink/af_netlink.c:1497
Code: 49 89 fe 49 bc 00 00 00 00 00 fc ff df e8 a4 5c 42 f8 4c 89 b4 24 80 00 00 00 49 83 c6 30 e8 f3 b8 d8 01 4c 89 f0 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 f7 e8 2d 55 a4 f8 4c 8b ac 24 80 00 00
RSP: 0018:ffffc90000be74d0 EFLAGS: 00010216
RAX: 0000000000000006 RBX: ffff8880308b0dc0 RCX: ffff88801af38000
RDX: 0000000000000000 RSI: ffff8880308b0dc0 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000cc0 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10022f06ec R12: dffffc0000000000
R13: 0000000000000018 R14: 0000000000000030 R15: 0000000000000018
FS:  0000000000000000(0000) GS:ffff8881260c7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f44f9bb7bac CR3: 000000006d60d000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 nlmsg_multicast_filtered include/net/netlink.h:1129 [inline]
 nlmsg_multicast include/net/netlink.h:1148 [inline]
 nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2577
 __devinet_sysctl_unregister net/ipv4/devinet.c:2705 [inline]
 devinet_sysctl_unregister net/ipv4/devinet.c:2729 [inline]
 inetdev_destroy net/ipv4/devinet.c:334 [inline]
 inetdev_event+0x77f/0x15b0 net/ipv4/devinet.c:1656
 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
 call_netdevice_notifiers net/core/dev.c:2228 [inline]
 unregister_netdevice_many_notify+0x15d8/0x2330 net/core/dev.c:11970
 unregister_netdevice_many net/core/dev.c:12034 [inline]
 default_device_exit_batch+0x819/0x890 net/core/dev.c:12528
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x7ac/0xbd0 net/core/net_namespace.c:654
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:read_pnet include/net/net_namespace.h:409 [inline]
RIP: 0010:sock_net include/net/sock.h:664 [inline]
RIP: 0010:netlink_broadcast_filtered+0x54/0x1140 net/netlink/af_netlink.c:1497
Code: 49 89 fe 49 bc 00 00 00 00 00 fc ff df e8 a4 5c 42 f8 4c 89 b4 24 80 00 00 00 49 83 c6 30 e8 f3 b8 d8 01 4c 89 f0 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 f7 e8 2d 55 a4 f8 4c 8b ac 24 80 00 00
RSP: 0018:ffffc90000be74d0 EFLAGS: 00010216
RAX: 0000000000000006 RBX: ffff8880308b0dc0 RCX: ffff88801af38000
RDX: 0000000000000000 RSI: ffff8880308b0dc0 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000cc0 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10022f06ec R12: dffffc0000000000
R13: 0000000000000018 R14: 0000000000000030 R15: 0000000000000018
FS:  0000000000000000(0000) GS:ffff8881260c7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2fe9e8 CR3: 0000000031110000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	49 89 fe             	mov    %rdi,%r14
   3:	49 bc 00 00 00 00 00 	movabs $0xdffffc0000000000,%r12
   a:	fc ff df
   d:	e8 a4 5c 42 f8       	call   0xf8425cb6
  12:	4c 89 b4 24 80 00 00 	mov    %r14,0x80(%rsp)
  19:	00
  1a:	49 83 c6 30          	add    $0x30,%r14
  1e:	e8 f3 b8 d8 01       	call   0x1d8b916
  23:	4c 89 f0             	mov    %r14,%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:	4c 89 f7             	mov    %r14,%rdi
  34:	e8 2d 55 a4 f8       	call   0xf8a45566
  39:	4c                   	rex.WR
  3a:	8b                   	.byte 0x8b
  3b:	ac                   	lods   %ds:(%rsi),%al
  3c:	24 80                	and    $0x80,%al

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/14 06:08 upstream 405e6c37c89e 7344edeb .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in netlink_broadcast_filtered
2025/06/03 17:44 upstream 546b1c9e93c2 a30356b7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in netlink_broadcast_filtered
* Struck through repros no longer work on HEAD.