Hello, syzbot found the following issue on: HEAD commit: 8755ae45a9e8 Add linux-next specific files for 20220819 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=10d3e2d3080000 kernel config: https://syzkaller.appspot.com/x/.config?x=ead6107a3bbe3c62 dashboard link: https://syzkaller.appspot.com/bug?extid=9fc084a4348493ef65d2 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1136b1a5080000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10bb167b080000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9fc084a4348493ef65d2@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.0.0-rc1-next-20220819-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:2/38 is trying to acquire lock: ffff888026598d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: do_strp_work net/strparser/strparser.c:398 [inline] ffff888026598d30 (sk_lock-AF_INET){+.+.}-{0:0}, at: strp_work+0x40/0x130 net/strparser/strparser.c:415 but task is already holding lock: ffffc90000af7da8 ((work_completion)(&strp->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 ((work_completion)(&strp->work)){+.+.}-{0:0}: __flush_work+0x105/0xae0 kernel/workqueue.c:3069 __cancel_work_timer+0x3f9/0x570 kernel/workqueue.c:3160 strp_done+0x64/0xf0 net/strparser/strparser.c:513 kcm_attach net/kcm/kcmsock.c:1429 [inline] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] kcm_ioctl+0x913/0x1180 net/kcm/kcmsock.c:1696 sock_do_ioctl+0xcc/0x230 net/socket.c:1169 sock_ioctl+0x2f1/0x640 net/socket.c:1286 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (sk_lock-AF_INET){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 lock_sock_nested+0x36/0xf0 net/core/sock.c:3391 do_strp_work net/strparser/strparser.c:398 [inline] strp_work+0x40/0x130 net/strparser/strparser.c:415 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((work_completion)(&strp->work)); lock(sk_lock-AF_INET); lock((work_completion)(&strp->work)); lock(sk_lock-AF_INET); *** DEADLOCK *** 2 locks held by kworker/u4:2/38: #0: ffff88802642d138 ((wq_completion)kstrp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88802642d138 ((wq_completion)kstrp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff88802642d138 ((wq_completion)kstrp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff88802642d138 ((wq_completion)kstrp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff88802642d138 ((wq_completion)kstrp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff88802642d138 ((wq_completion)kstrp){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc90000af7da8 ((work_completion)(&strp->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 stack backtrace: CPU: 1 PID: 38 Comm: kworker/u4:2 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0 kworker/u4:2[38] cmdline: ��a����� Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: kstrp strp_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:122 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 lock_sock_nested+0x36/0xf0 net/core/sock.c:3391 do_strp_work net/strparser/strparser.c:398 [inline] strp_work+0x40/0x130 net/strparser/strparser.c:415 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> --- This report is generated by a bot. 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