syzbot


WARNING: bad unlock balance in do_setlink

Status: upstream: reported C repro on 2025/04/07 05:57
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+45016fe295243a7882d3@syzkaller.appspotmail.com
First crash: 3d23h, last: 40m
Cause bisection: introduced by (bisect log) :
commit dbfc99495d960134bfe1a4f13849fb0d5373b42c
Author: Stanislav Fomichev <sdf@fomichev.me>
Date: Tue Apr 1 16:34:47 2025 +0000

  net: dummy: request ops lock

Crash: WARNING: bad unlock balance in do_setlink (log)
Repro: C syz .config
  
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [net?] WARNING: bad unlock balance in do_setlink 4 (6) 2025/04/08 08:11
[PATCH v1 net] rtnetlink: Fix bad unlock balance in do_setlink(). 2 (2) 2025/04/07 16:57
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/04/07 06:37 1h11m kuniyu@amazon.com patch net report log

Sample crash report:
=====================================
WARNING: bad unlock balance detected!
6.14.0-syzkaller-12504-g8bc251e5d874 #0 Not tainted
-------------------------------------
syz-executor814/5834 is trying to release lock (&dev_instance_lock_key) at:
[<ffffffff89f41f56>] netdev_unlock include/linux/netdevice.h:2756 [inline]
[<ffffffff89f41f56>] netdev_unlock_ops include/net/netdev_lock.h:48 [inline]
[<ffffffff89f41f56>] do_setlink+0xc26/0x43a0 net/core/rtnetlink.c:3406
but there are no more locks to release!

other info that might help us debug this:
1 lock held by syz-executor814/5834:
 #0: ffffffff900fc408 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff900fc408 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff900fc408 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4064

stack backtrace:
CPU: 0 UID: 0 PID: 5834 Comm: syz-executor814 Not tainted 6.14.0-syzkaller-12504-g8bc251e5d874 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_unlock_imbalance_bug+0x185/0x1a0 kernel/locking/lockdep.c:5296
 __lock_release kernel/locking/lockdep.c:5535 [inline]
 lock_release+0x1ed/0x3e0 kernel/locking/lockdep.c:5887
 __mutex_unlock_slowpath+0xee/0x800 kernel/locking/mutex.c:907
 netdev_unlock include/linux/netdevice.h:2756 [inline]
 netdev_unlock_ops include/net/netdev_lock.h:48 [inline]
 do_setlink+0xc26/0x43a0 net/core/rtnetlink.c:3406
 rtnl_group_changelink net/core/rtnetlink.c:3783 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3937 [inline]
 rtnl_newlink+0x1619/0x1fe0 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x80f/0xd70 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8c3/0xcd0 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:727
 ____sys_sendmsg+0x523/0x860 net/socket.c:2566
 ___sys_sendmsg net/socket.c:2620 [inline]
 __sys_sendmsg+0x271/0x360 net/socket.c:2652
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8427b614a9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff9b59f3a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fff9b59f578 RCX: 00007f8427b614a9
RDX: 0000000000000000 RSI: 0000200000000300 RDI: 0000000000000004
RBP: 00007f8427bd4610 R08: 000000000000000c R09: 00007fff9b59f578
R10: 000000000000001b R11: 0000000000000246 R12: 0000000000000001
R13:

Crashes (289):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/04 12:33 net 8bc251e5d874 d7ae3a11 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 17:42 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING: bad unlock balance in do_setlink
2025/04/07 08:12 upstream 0af2f6be1b42 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 08:11 upstream 0af2f6be1b42 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 22:12 upstream 16cd1c265776 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 19:21 upstream 16cd1c265776 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 15:46 upstream f4d2ef48250a 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING: bad unlock balance in do_setlink
2025/04/06 07:42 upstream f4d2ef48250a 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 01:47 upstream a8662bcd2ff1 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING: bad unlock balance in do_setlink
2025/04/05 20:12 upstream a8662bcd2ff1 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/05 15:27 upstream a8662bcd2ff1 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING: bad unlock balance in do_setlink
2025/04/08 04:39 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING: bad unlock balance in do_setlink
2025/04/08 01:20 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING: bad unlock balance in do_setlink
2025/04/08 00:27 upstream 0af2f6be1b42 a2ada0e7 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING: bad unlock balance in do_setlink
2025/04/07 17:58 upstream 0af2f6be1b42 2f0c9720 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING: bad unlock balance in do_setlink
2025/04/07 15:36 upstream 0af2f6be1b42 2f0c9720 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING: bad unlock balance in do_setlink
2025/04/07 11:06 upstream 0af2f6be1b42 2f0c9720 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING: bad unlock balance in do_setlink
2025/04/07 03:09 upstream dda888789496 1c65791e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING: bad unlock balance in do_setlink
2025/04/06 18:03 upstream f4d2ef48250a 1c65791e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING: bad unlock balance in do_setlink
2025/04/06 00:38 upstream 56f944529ec2 1c65791e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING: bad unlock balance in do_setlink
2025/04/05 22:29 upstream 56f944529ec2 1c65791e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING: bad unlock balance in do_setlink
2025/04/07 19:09 upstream 0af2f6be1b42 2f0c9720 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING: bad unlock balance in do_setlink
2025/04/08 10:02 net 69ae94725f4f a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/08 08:24 net 04efcee6ef8d a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/08 03:30 net 04efcee6ef8d a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/08 02:25 net 04efcee6ef8d a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 22:53 net 04efcee6ef8d a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 20:23 net 04efcee6ef8d a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 16:41 net 61f96e684edd a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 14:44 net 61f96e684edd a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 13:35 net 61f96e684edd a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 12:11 net 61f96e684edd a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 07:09 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 05:43 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 04:32 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 01:45 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 01:43 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 00:42 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 20:21 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 16:49 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 14:28 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 12:56 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 11:04 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 06:12 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 05:03 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 03:43 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/05 16:59 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/05 15:44 net 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/08 05:04 net-next 61f96e684edd a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/07 09:48 net-next 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/06 15:34 net-next 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/05 23:33 net-next 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/05 18:39 net-next 61f96e684edd 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING: bad unlock balance in do_setlink
2025/04/08 06:33 linux-next 7702d0130dc0 a2ada0e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: bad unlock balance in do_setlink
* Struck through repros no longer work on HEAD.