audit: type=1800 audit(1648116092.542:59): pid=15058 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="sda1" ino=14503 res=0 BTRFS: device fsid f90cac8b-044b-4fa8-8bee-4b8d3da88dc2 devid 1 transid 7 /dev/loop2 ====================================================== WARNING: possible circular locking dependency detected 4.14.273-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:1/22 is trying to acquire lock: (sk_lock-AF_INET){+.+.}, at: [] do_strp_work net/strparser/strparser.c:415 [inline] (sk_lock-AF_INET){+.+.}, at: [] strp_work+0x3e/0x100 net/strparser/strparser.c:434 but task is already holding lock: ((&strp->work)){+.+.}, at: [] 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:2816 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/u4:1/22: #0: ("%s""kstrp"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: ((&strp->work)){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 stack backtrace: CPU: 0 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.273-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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:2816 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 BTRFS info (device loop2): disk space caching is enabled BTRFS info (device loop2): has skinny extents audit: type=1800 audit(1648116093.472:60): pid=15125 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="sda1" ino=14501 res=0 audit: type=1800 audit(1648116094.392:61): pid=15143 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="sda1" ino=14097 res=0 BTRFS info (device loop2): disk space caching is enabled BTRFS info (device loop2): has skinny extents audit: type=1804 audit(1648116096.122:62): pid=15243 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/193/file0/bus" dev="ramfs" ino=43909 res=1 audit: type=1800 audit(1648116096.132:63): pid=15245 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="sda1" ino=14543 res=0 audit: type=1804 audit(1648116096.142:64): pid=15243 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/193/file0/bus" dev="ramfs" ino=43909 res=1 BTRFS info (device loop1): disk space caching is enabled BTRFS info (device loop1): has skinny extents audit: type=1804 audit(1648116096.382:65): pid=15269 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/194/file0/bus" dev="ramfs" ino=44579 res=1 audit: type=1804 audit(1648116096.412:66): pid=15269 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/194/file0/bus" dev="ramfs" ino=44579 res=1 audit: type=1804 audit(1648116096.602:67): pid=15296 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/188/file0/bus" dev="ramfs" ino=44597 res=1 audit: type=1804 audit(1648116096.642:68): pid=15296 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/188/file0/bus" dev="ramfs" ino=44597 res=1 kauditd_printk_skb: 3 callbacks suppressed audit: type=1804 audit(1648116097.552:72): pid=15324 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/195/file0/bus" dev="ramfs" ino=43987 res=1 audit: type=1804 audit(1648116097.682:73): pid=15328 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/189/file0/bus" dev="ramfs" ino=43990 res=1 audit: type=1804 audit(1648116097.762:74): pid=15328 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/189/file0/bus" dev="ramfs" ino=43990 res=1 audit: type=1804 audit(1648116098.352:75): pid=15335 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir3020540517/syzkaller.roAbas/171/file0/bus" dev="ramfs" ino=43998 res=1 audit: type=1804 audit(1648116098.432:76): pid=15335 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir3020540517/syzkaller.roAbas/171/file0/bus" dev="ramfs" ino=43998 res=1 audit: type=1804 audit(1648116098.532:77): pid=15344 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/196/file0/bus" dev="ramfs" ino=44008 res=1 audit: type=1804 audit(1648116098.562:78): pid=15344 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir3494147439/syzkaller.kjjFao/196/file0/bus" dev="ramfs" ino=44008 res=1 audit: type=1804 audit(1648116098.762:79): pid=15355 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/190/file0/bus" dev="ramfs" ino=44020 res=1 audit: type=1804 audit(1648116098.812:80): pid=15355 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/190/file0/bus" dev="ramfs" ino=44020 res=1 audit: type=1804 audit(1648116100.522:81): pid=15378 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir150887463/syzkaller.JvPWRa/191/file0/bus" dev="ramfs" ino=45077 res=1 BTRFS info (device loop5): disk space caching is enabled BTRFS info (device loop5): has skinny extents