IPv6: ADDRCONF(NETDEV_CHANGE): macvtap0: link becomes ready
batman_adv: batadv0: Interface activated: batadv_slave_1
IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready
======================================================
WARNING: possible circular locking dependency detected
4.14.285-syzkaller #0 Not tainted
------------------------------------------------------
kworker/u4:0/5 is trying to acquire lock:
(sk_lock-AF_INET){+.+.}, at: [<ffffffff8681de3e>] do_strp_work net/strparser/strparser.c:415 [inline]
(sk_lock-AF_INET){+.+.}, at: [<ffffffff8681de3e>] strp_work+0x3e/0x100 net/strparser/strparser.c:434
but task is already holding lock:
((&strp->work)){+.+.}, at: [<ffffffff81364f26>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 ((&strp->work)){+.+.}:
flush_work+0xad/0x770 kernel/workqueue.c:2890
__cancel_work_timer+0x321/0x460 kernel/workqueue.c:2965
strp_done+0x53/0xd0 net/strparser/strparser.c:519
kcm_attach net/kcm/kcmsock.c:1429 [inline]
kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline]
kcm_ioctl+0x828/0xfb0 net/kcm/kcmsock.c:1701
sock_do_ioctl net/socket.c:974 [inline]
sock_ioctl+0x2cc/0x4c0 net/socket.c:1071
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:500 [inline]
do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
-> #0 (sk_lock-AF_INET){+.+.}:
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
lock_sock_nested+0xb7/0x100 net/core/sock.c:2813
do_strp_work net/strparser/strparser.c:415 [inline]
strp_work+0x3e/0x100 net/strparser/strparser.c:434
process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock((&strp->work));
lock(sk_lock-AF_INET);
lock((&strp->work));
lock(sk_lock-AF_INET);
*** DEADLOCK ***
2 locks held by kworker/u4:0/5:
#0: ("%s""kstrp"){+.+.}, at: [<ffffffff81364ef0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088
#1: ((&strp->work)){+.+.}, at: [<ffffffff81364f26>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092
stack backtrace:
CPU: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.285-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/18/2022
Workqueue: kstrp strp_work
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258
check_prev_add kernel/locking/lockdep.c:1905 [inline]
check_prevs_add kernel/locking/lockdep.c:2022 [inline]
validate_chain kernel/locking/lockdep.c:2464 [inline]
__lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
lock_sock_nested+0xb7/0x100 net/core/sock.c:2813
do_strp_work net/strparser/strparser.c:415 [inline]
strp_work+0x3e/0x100 net/strparser/strparser.c:434
process_one_work+0x793/0x14a0 kernel/workqueue.c:2117