4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx> commit e8e3437762ad938880dd48a3c52d702e7cf3c124 upstream. We might have never enabled (started) the psock's parser, in which case it will not get stopped when destroying the psock. This leads to a warning when trying to cancel parser's work from psock's deferred destructor: [ 405.325769] WARNING: CPU: 1 PID: 3216 at net/strparser/strparser.c:526 strp_done+0x3c/0x40 [ 405.326712] Modules linked in: [last unloaded: test_bpf] [ 405.327359] CPU: 1 PID: 3216 Comm: kworker/1:164 Tainted: G W 5.0.0 #42 [ 405.328294] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20180531_142017-buildhw-08.phx2.fedoraproject.org-1.fc28 04/01/2014 [ 405.329712] Workqueue: events sk_psock_destroy_deferred [ 405.330254] RIP: 0010:strp_done+0x3c/0x40 [ 405.330706] Code: 28 e8 b8 d5 6b ff 48 8d bb 80 00 00 00 e8 9c d5 6b ff 48 8b 7b 18 48 85 ff 74 0d e8 1e a5 e8 ff 48 c7 43 18 00 00 00 00 5b c3 <0f> 0b eb cf 66 66 66 66 90 55 89 f5 53 48 89 fb 48 83 c7 28 e8 0b [ 405.332862] RSP: 0018:ffffc900026bbe50 EFLAGS: 00010246 [ 405.333482] RAX: ffffffff819323e0 RBX: ffff88812cb83640 RCX: ffff88812cb829e8 [ 405.334228] RDX: 0000000000000001 RSI: ffff88812cb837e8 RDI: ffff88812cb83640 [ 405.335366] RBP: ffff88813fd22680 R08: 0000000000000000 R09: 000073746e657665 [ 405.336472] R10: 8080808080808080 R11: 0000000000000001 R12: ffff88812cb83600 [ 405.337760] R13: 0000000000000000 R14: ffff88811f401780 R15: ffff88812cb837e8 [ 405.338777] FS: 0000000000000000(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000 [ 405.339903] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 405.340821] CR2: 00007fb11489a6b8 CR3: 000000012d4d6000 CR4: 00000000000406e0 [ 405.341981] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 405.343131] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 405.344415] Call Trace: [ 405.344821] sk_psock_destroy_deferred+0x23/0x1b0 [ 405.345585] process_one_work+0x1ae/0x3e0 [ 405.346110] worker_thread+0x3c/0x3b0 [ 405.346576] ? pwq_unbound_release_workfn+0xd0/0xd0 [ 405.347187] kthread+0x11d/0x140 [ 405.347601] ? __kthread_parkme+0x80/0x80 [ 405.348108] ret_from_fork+0x35/0x40 [ 405.348566] ---[ end trace a4a3af4026a327d4 ]--- Stop psock's parser just before canceling its work. Fixes: 1d79895aef18 ("sk_msg: Always cancel strp work before freeing the psock") Reported-by: kernel test robot <rong.a.chen@xxxxxxxxx> Signed-off-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/core/skmsg.c | 1 + 1 file changed, 1 insertion(+) --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -545,6 +545,7 @@ static void sk_psock_destroy_deferred(st struct sk_psock *psock = container_of(gc, struct sk_psock, gc); /* No sk_callback_lock since already detached. */ + strp_stop(&psock->parser.strp); strp_done(&psock->parser.strp); cancel_work_sync(&psock->work);