./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor4052610006 <...> forked to background, child pid 3178 [ 27.733072][ T3179] 8021q: adding VLAN 0 to HW filter on device bond0 [ 27.744609][ T3179] eql: remember to turn off Van-Jacobson compression on your slave devices [ 27.995532][ T3263] ssh-keygen (3263) used greatest stack depth: 22432 bytes left Starting sshd: OK syzkaller Warning: Permanently added '10.128.1.12' (ECDSA) to the list of known hosts. execve("./syz-executor4052610006", ["./syz-executor4052610006"], 0x7fffe4051c20 /* 10 vars */) = 0 brk(NULL) = 0x555556427000 brk(0x555556427c40) = 0x555556427c40 arch_prctl(ARCH_SET_FS, 0x555556427300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 set_tid_address(0x5555564275d0) = 3607 set_robust_list(0x5555564275e0, 24) = 0 rt_sigaction(SIGRTMIN, {sa_handler=0x7f44469ffc30, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f4446a00300}, NULL, 8) = 0 rt_sigaction(SIGRT_1, {sa_handler=0x7f44469ffcd0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f4446a00300}, NULL, 8) = 0 rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0 prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0 readlink("/proc/self/exe", "/root/syz-executor4052610006", 4096) = 28 brk(0x555556448c40) = 0x555556448c40 brk(0x555556449000) = 0x555556449000 mprotect(0x7f4446ac0000, 16384, PROT_READ) = 0 mmap(0x1ffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x1ffff000 mmap(0x20000000, 16777216, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000 mmap(0x21000000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x21000000 futex(0x7f4446ac640c, FUTEX_WAKE_PRIVATE, 1000000) = 0 mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f44469d0000 mprotect(0x7f44469d1000, 131072, PROT_READ|PROT_WRITE) = 0 clone(child_stack=0x7f44469f03f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[3608], tls=0x7f44469f0700, child_tidptr=0x7f44469f09d0) = 3608 ./strace-static-x86_64: Process 3608 attached [pid 3607] futex(0x7f4446ac6408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3607] futex(0x7f4446ac640c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3608] set_robust_list(0x7f44469f09e0, 24) = 0 [pid 3608] pipe([3, 4]) = 0 [pid 3608] futex(0x7f4446ac640c, FUTEX_WAKE_PRIVATE, 1000000) = 1 [pid 3607] <... futex resumed>) = 0 [pid 3607] futex(0x7f4446ac6408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3607] futex(0x7f4446ac640c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3608] pipe2([5, 6], O_EXCL) = 0 [pid 3608] futex(0x7f4446ac640c, FUTEX_WAKE_PRIVATE, 1000000) = 1 [pid 3607] <... futex resumed>) = 0 [pid 3607] futex(0x7f4446ac6408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3607] futex(0x7f4446ac640c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3608] splice(3, NULL, 6, NULL, 511, 0 [pid 3607] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out) [pid 3607] futex(0x7f4446ac641c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3607] mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f44469af000 [pid 3607] mprotect(0x7f44469b0000, 131072, PROT_READ|PROT_WRITE) = 0 [pid 3607] clone(child_stack=0x7f44469cf3f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID./strace-static-x86_64: Process 3609 attached , parent_tid=[3609], tls=0x7f44469cf700, child_tidptr=0x7f44469cf9d0) = 3609 [pid 3607] futex(0x7f4446ac6418, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3607] futex(0x7f4446ac641c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3609] set_robust_list(0x7f44469cf9e0, 24) = 0 [pid 3609] vmsplice(4, [{iov_base="\xb5", iov_len=1}], 1, 0) = 1 [pid 3609] futex(0x7f4446ac641c, FUTEX_WAKE_PRIVATE, 1000000) = 1 [pid 3607] <... futex resumed>) = 0 syzkaller login: [ 51.357531][ T3608] [ 51.359885][ T3608] ============================================ [ 51.366013][ T3608] WARNING: possible recursive locking detected [ 51.372143][ T3608] 5.19.0-rc4-next-20220628-syzkaller #0 Not tainted [ 51.378707][ T3608] -------------------------------------------- [ 51.384832][ T3608] syz-executor405/3608 is trying to acquire lock: [ 51.392191][ T3608] ffff88807d166068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x132/0x1bf0 [ 51.400964][ T3608] [ 51.400964][ T3608] but task is already holding lock: [ 51.408307][ T3608] ffff88807d166468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 51.417686][ T3608] [ 51.417686][ T3608] other info that might help us debug this: [ 51.425745][ T3608] Possible unsafe locking scenario: [ 51.425745][ T3608] [ 51.433178][ T3608] CPU0 [ 51.436454][ T3608] ---- [ 51.439716][ T3608] lock(&pipe->mutex/1); [ 51.444033][ T3608] lock(&pipe->mutex/1); [ 51.448350][ T3608] [ 51.448350][ T3608] *** DEADLOCK *** [ 51.448350][ T3608] [ 51.456473][ T3608] May be due to missing lock nesting notation [ 51.456473][ T3608] [ 51.464774][ T3608] 1 lock held by syz-executor405/3608: [ 51.470212][ T3608] #0: ffff88807d166468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 51.480066][ T3608] [ 51.480066][ T3608] stack backtrace: [ 51.485932][ T3608] CPU: 0 PID: 3608 Comm: syz-executor405 Not tainted 5.19.0-rc4-next-20220628-syzkaller #0 [ 51.495888][ T3608] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 [ 51.505925][ T3608] Call Trace: [ 51.509195][ T3608] [ 51.512112][ T3608] dump_stack_lvl+0xcd/0x134 [ 51.516705][ T3608] __lock_acquire.cold+0x1f5/0x3b4 [ 51.521807][ T3608] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 51.527776][ T3608] lock_acquire+0x1ab/0x570 [ 51.532263][ T3608] ? pipe_write+0x132/0x1bf0 [ 51.536845][ T3608] ? lock_release+0x780/0x780 [ 51.541509][ T3608] __mutex_lock+0x12f/0x1350 [ 51.546086][ T3608] ? pipe_write+0x132/0x1bf0 [ 51.550662][ T3608] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 51.556627][ T3608] ? pipe_write+0x132/0x1bf0 [ 51.561202][ T3608] ? mutex_lock_io_nested+0x1190/0x1190 [ 51.566734][ T3608] ? find_held_lock+0x2d/0x110 [ 51.571492][ T3608] ? aa_file_perm+0x56b/0x1230 [ 51.576244][ T3608] ? lock_downgrade+0x6e0/0x6e0 [ 51.581079][ T3608] pipe_write+0x132/0x1bf0 [ 51.585488][ T3608] ? aa_file_perm+0x595/0x1230 [ 51.590240][ T3608] ? do_proc_dopipe_max_size_conv+0x1c0/0x1c0 [ 51.596292][ T3608] ? aa_path_link+0x2f0/0x2f0 [ 51.600957][ T3608] ? mutex_lock_io_nested+0x1190/0x1190 [ 51.606492][ T3608] ? pipe_wait_readable+0x336/0x420 [ 51.611675][ T3608] ? lock_downgrade+0x6e0/0x6e0 [ 51.616513][ T3608] do_iter_readv_writev+0x360/0x5c0 [ 51.621716][ T3608] ? ksys_lseek+0x1b0/0x1b0 [ 51.626205][ T3608] ? bpf_lsm_file_permission+0x5/0x10 [ 51.631565][ T3608] ? security_file_permission+0xab/0xd0 [ 51.637098][ T3608] do_iter_write+0x182/0x700 [ 51.641677][ T3608] vfs_iter_write+0x70/0xa0 [ 51.646163][ T3608] iter_file_splice_write+0x723/0xc70 [ 51.651526][ T3608] ? page_cache_pipe_buf_confirm+0x5b0/0x5b0 [ 51.657496][ T3608] ? __lock_acquire+0xbca/0x5660 [ 51.662422][ T3608] ? bpf_lsm_file_permission+0x5/0x10 [ 51.667786][ T3608] ? security_file_permission+0xab/0xd0 [ 51.673320][ T3608] ? page_cache_pipe_buf_confirm+0x5b0/0x5b0 [ 51.679298][ T3608] do_splice+0xb57/0x1920 [ 51.683608][ T3608] ? find_held_lock+0x2d/0x110 [ 51.688365][ T3608] ? splice_file_to_pipe+0x120/0x120 [ 51.693633][ T3608] ? lock_downgrade+0x6e0/0x6e0 [ 51.698470][ T3608] __do_splice+0x134/0x250 [ 51.702871][ T3608] ? do_splice+0x1920/0x1920 [ 51.707450][ T3608] __x64_sys_splice+0x198/0x250 [ 51.712288][ T3608] do_syscall_64+0x35/0xb0 [ 51.716703][ T3608] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 51.722597][ T3608] RIP: 0033:0x7f4446a3dc99 [ 51.727080][ T3608] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [ 51.746671][ T3608] RSP: 002b:00007f44469f0308 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [pid 3609] futex(0x7f4446ac6418, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3608] <... splice resumed>) = -1 EXDEV (Invalid cross-device link) [pid 3608] futex(0x7f4446ac640c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3608] futex(0x7f4446ac6408, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3607] exit_group(0) = ? [pid 3609] <... futex resumed>) = ? [pid 3609] +++ exited with 0 +++ [pid 3608] <... futex resumed>) = ? [pid 3608] +++ exited with 0 +++ +++ exited with 0 +++ [ 51.755063][ T3608] RAX: ffffffffffffffda RBX: