Re: [moderation/CI] Re: vsock/virtio: fix memory leak in virtio_transport_recv_listen

#syz upstream


On Sat, Jun 6, 2026 at 3:33 AM syzbot ci
<[email protected]> wrote:
>
> syzbot ci has tested the following series
>
> [v1] vsock/virtio: fix memory leak in virtio_transport_recv_listen
> https://lore.kernel.org/all/[email protected]
> * [PATCH] vsock/virtio: fix memory leak in virtio_transport_recv_listen
>
> and found the following issue:
> possible deadlock in virtio_transport_recv_listen
>
> Full report is available here:
> https://ci.syzbot.org/series/76f40e62-5a21-46d4-a636-10f0ec9c5040
>
> ***
>
> possible deadlock in virtio_transport_recv_listen
>
> tree:      net-next
> URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/netdev/net-next.git
> base:      bfa3d89cc15c09f7d1581c834a5ed725189ec19f
> arch:      amd64
> compiler:  Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
> config:    https://ci.syzbot.org/builds/5a94a424-94b1-4b1e-8b06-74d59933368f/config
> syz repro: https://ci.syzbot.org/findings/a8224003-11b3-4232-a635-6755ad892149/syz_repro
>
> ============================================
> WARNING: possible recursive locking detected
> syzkaller #0 Not tainted
> --------------------------------------------
> kworker/0:3/5740 is trying to acquire lock:
> ffff88810efb62a0 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
> ffff88810efb62a0 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: virtio_transport_recv_listen+0x964/0x2120 net/vmw_vsock/virtio_transport_common.c:1577
>
> but task is already holding lock:
> ffff88810efb62a0 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
> ffff88810efb62a0 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: virtio_transport_recv_pkt+0xa26/0x2800 net/vmw_vsock/virtio_transport_common.c:1668
>
> other info that might help us debug this:
>  Possible unsafe locking scenario:
>
>        CPU0
>        ----
>   lock(sk_lock-AF_VSOCK);
>   lock(sk_lock-AF_VSOCK);
>
>  *** DEADLOCK ***
>
>  May be due to missing lock nesting notation
>
> 4 locks held by kworker/0:3/5740:
>  #0: ffff8881150d3540 ((wq_completion)vsock-loopback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
>  #0: ffff8881150d3540 ((wq_completion)vsock-loopback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
>  #1: ffffc90003fafc40 ((work_completion)(&vsock->pkt_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
>  #1: ffffc90003fafc40 ((work_completion)(&vsock->pkt_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
>  #2: ffff88810efb62a0 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
>  #2: ffff88810efb62a0 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: virtio_transport_recv_pkt+0xa26/0x2800 net/vmw_vsock/virtio_transport_common.c:1668
>  #3: ffff88810efb5120 (sk_lock-AF_VSOCK/1){+.+.}-{0:0}, at: virtio_transport_recv_listen+0x83f/0x2120 net/vmw_vsock/virtio_transport_common.c:1564
>
> stack backtrace:
> CPU: 0 UID: 0 PID: 5740 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full)
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
> Workqueue: vsock-loopback vsock_loopback_work
> Call Trace:
>  <TASK>
>  dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
>  print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041
>  check_deadlock kernel/locking/lockdep.c:3093 [inline]
>  validate_chain kernel/locking/lockdep.c:3895 [inline]
>  __lock_acquire+0x253f/0x2cf0 kernel/locking/lockdep.c:5237
>  lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
>  lock_sock_nested+0x41/0x100 net/core/sock.c:3790
>  lock_sock include/net/sock.h:1713 [inline]
>  virtio_transport_recv_listen+0x964/0x2120 net/vmw_vsock/virtio_transport_common.c:1577
>  virtio_transport_recv_pkt+0x1570/0x2800 net/vmw_vsock/virtio_transport_common.c:1692
>  vsock_loopback_work+0x32c/0x3f0 net/vmw_vsock/vsock_loopback.c:142
>  process_one_work kernel/workqueue.c:3314 [inline]
>  process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397
>  worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478
>  kthread+0x389/0x470 kernel/kthread.c:436
>  ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
>  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
>  </TASK>
>
>
> ***
>
> If these findings have caused you to resend the series or submit a
> separate fix, please add the following tag to your commit message:
>   Tested-by: [email protected]
>
> ---
> This report is generated by a bot. It may contain errors.
> syzbot ci engineers can be reached at [email protected].
>
> To test a patch for this bug, please reply with `#syz test`
> (should be on a separate line).
>
> The patch should be attached to the email.
> Note: arguments like custom git repos and branches are not supported.
>
> The email will later be sent to:
> [[email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected] [email protected]]
>
> If the report looks fine to you, reply with:
> #syz upstream
>
> If the report is a false positive, reply with
> #syz invalid
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-upstream-moderation" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
> To view this discussion visit https://groups.google.com/d/msgid/syzkaller-upstream-moderation/6a236acc.c25708ab.1b19ef.0000.GAE%40google.com.