./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor1834049347 <...> [ 29.764853][ T3186] 8021q: adding VLAN 0 to HW filter on device bond0 [ 29.778601][ T3186] eql: remember to turn off Van-Jacobson compression on your slave devices Starting sshd: OK syzkaller syzkaller login: [ 40.788111][ T27] kauditd_printk_skb: 37 callbacks suppressed [ 40.788122][ T27] audit: type=1400 audit(1660833964.323:73): avc: denied { transition } for pid=3422 comm="sshd" path="/bin/sh" dev="sda1" ino=73 scontext=system_u:system_r:initrc_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [ 40.822399][ T27] audit: type=1400 audit(1660833964.353:74): avc: denied { write } for pid=3422 comm="sh" path="pipe:[28857]" dev="pipefs" ino=28857 scontext=root:sysadm_r:sysadm_t tcontext=system_u:system_r:initrc_t tclass=fifo_file permissive=1 Warning: Permanently added '10.128.0.124' (ECDSA) to the list of known hosts. execve("./syz-executor1834049347", ["./syz-executor1834049347"], 0x7ffcdf929a00 /* 10 vars */) = 0 brk(NULL) = 0x555555e10000 brk(0x555555e10c40) = 0x555555e10c40 arch_prctl(ARCH_SET_FS, 0x555555e10300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 set_tid_address(0x555555e105d0) = 3614 set_robust_list(0x555555e105e0, 24) = 0 rt_sigaction(SIGRTMIN, {sa_handler=0x7f19d7c03c30, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f19d7c04300}, NULL, 8) = 0 rt_sigaction(SIGRT_1, {sa_handler=0x7f19d7c03cd0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f19d7c04300}, 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-executor1834049347", 4096) = 28 brk(0x555555e31c40) = 0x555555e31c40 brk(0x555555e32000) = 0x555555e32000 mprotect(0x7f19d7cc4000, 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(0x7f19d7cca40c, FUTEX_WAKE_PRIVATE, 1000000) = 0 mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f19d7bd4000 mprotect(0x7f19d7bd5000, 131072, PROT_READ|PROT_WRITE) = 0 clone(child_stack=0x7f19d7bf43f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[3615], tls=0x7f19d7bf4700, child_tidptr=0x7f19d7bf49d0) = 3615 futex(0x7f19d7cca408, FUTEX_WAKE_PRIVATE, 1000000) = 0 futex(0x7f19d7cca40c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000}./strace-static-x86_64: Process 3615 attached [pid 3615] set_robust_list(0x7f19d7bf49e0, 24) = 0 [pid 3615] pipe([3, 4]) = 0 [pid 3615] futex(0x7f19d7cca40c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3614] <... futex resumed>) = 0 [pid 3614] futex(0x7f19d7cca408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3614] futex(0x7f19d7cca40c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3615] <... futex resumed>) = 1 [pid 3615] pipe2([5, 6], O_EXCL) = 0 [pid 3615] futex(0x7f19d7cca40c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3614] <... futex resumed>) = 0 [pid 3614] futex(0x7f19d7cca408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3614] futex(0x7f19d7cca40c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3615] <... futex resumed>) = 1 [ 52.011254][ T27] audit: type=1400 audit(1660833975.543:75): avc: denied { execmem } for pid=3614 comm="syz-executor183" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [pid 3615] splice(3, NULL, 6, NULL, 511, 0 [pid 3614] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out) [pid 3614] futex(0x7f19d7cca41c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3614] mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f19d7bb3000 [pid 3614] mprotect(0x7f19d7bb4000, 131072, PROT_READ|PROT_WRITE) = 0 [pid 3614] clone(child_stack=0x7f19d7bd33f0, 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 3616 attached , parent_tid=[3616], tls=0x7f19d7bd3700, child_tidptr=0x7f19d7bd39d0) = 3616 [pid 3614] futex(0x7f19d7cca418, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3614] futex(0x7f19d7cca41c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3616] set_robust_list(0x7f19d7bd39e0, 24) = 0 [pid 3616] vmsplice(4, [{iov_base="\xb5", iov_len=1}], 1, 0) = 1 [pid 3616] futex(0x7f19d7cca41c, FUTEX_WAKE_PRIVATE, 1000000) = 1 [pid 3616] futex(0x7f19d7cca418, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3614] <... futex resumed>) = 0 [ 52.074525][ T3615] [ 52.076887][ T3615] ============================================ [ 52.083018][ T3615] WARNING: possible recursive locking detected [ 52.089149][ T3615] 6.0.0-rc1-syzkaller-00025-g274a2eebf80c #0 Not tainted [ 52.096156][ T3615] -------------------------------------------- [ 52.102293][ T3615] syz-executor183/3615 is trying to acquire lock: [ 52.108701][ T3615] ffff888077d08068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x132/0x1be0 [ 52.117481][ T3615] [ 52.117481][ T3615] but task is already holding lock: [ 52.124824][ T3615] ffff88801dc0c068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 52.134203][ T3615] [ 52.134203][ T3615] other info that might help us debug this: [ 52.142241][ T3615] Possible unsafe locking scenario: [ 52.142241][ T3615] [ 52.149668][ T3615] CPU0 [ 52.152926][ T3615] ---- [ 52.156186][ T3615] lock(&pipe->mutex/1); [ 52.160502][ T3615] lock(&pipe->mutex/1); [ 52.164834][ T3615] [ 52.164834][ T3615] *** DEADLOCK *** [ 52.164834][ T3615] [pid 3614] exit_group(0) = ? [pid 3616] <... futex resumed>) = ? [pid 3616] +++ exited with 0 +++ [ 52.172975][ T3615] May be due to missing lock nesting notation [ 52.172975][ T3615] [ 52.181291][ T3615] 1 lock held by syz-executor183/3615: [ 52.186747][ T3615] #0: ffff88801dc0c068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 52.196594][ T3615] [ 52.196594][ T3615] stack backtrace: [ 52.202467][ T3615] CPU: 0 PID: 3615 Comm: syz-executor183 Not tainted 6.0.0-rc1-syzkaller-00025-g274a2eebf80c #0 [ 52.212867][ T3615] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 [ 52.222906][ T3615] Call Trace: [ 52.226170][ T3615] [ 52.229171][ T3615] dump_stack_lvl+0xcd/0x134 [ 52.233773][ T3615] __lock_acquire.cold+0x116/0x3a7 [ 52.238867][ T3615] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 52.244919][ T3615] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 52.250887][ T3615] lock_acquire+0x1ab/0x570 [ 52.255374][ T3615] ? pipe_write+0x132/0x1be0 [ 52.259954][ T3615] ? lock_release+0x780/0x780 [ 52.264614][ T3615] __mutex_lock+0x12f/0x1350 [ 52.269203][ T3615] ? pipe_write+0x132/0x1be0 [ 52.273779][ T3615] ? avc_has_perm_noaudit+0x1f0/0x390 [ 52.279147][ T3615] ? pipe_write+0x132/0x1be0 [ 52.283720][ T3615] ? mutex_lock_io_nested+0x1190/0x1190 [ 52.289269][ T3615] ? lock_release+0x780/0x780 [ 52.293970][ T3615] pipe_write+0x132/0x1be0 [ 52.298371][ T3615] ? avc_has_perm_noaudit+0x390/0x390 [ 52.303727][ T3615] ? trace_contention_end+0xea/0x150 [ 52.309087][ T3615] ? __mutex_lock+0x231/0x1350 [ 52.313921][ T3615] ? do_proc_dopipe_max_size_conv+0x1c0/0x1c0 [ 52.320010][ T3615] ? file_has_perm+0x25a/0x340 [ 52.324771][ T3615] ? selinux_bprm_committing_creds+0x6f0/0x6f0 [ 52.331098][ T3615] do_iter_readv_writev+0x20b/0x3b0 [ 52.336290][ T3615] ? generic_copy_file_range+0xd0/0xd0 [ 52.341736][ T3615] ? security_file_permission+0xab/0xd0 [ 52.347366][ T3615] do_iter_write+0x182/0x700 [ 52.351960][ T3615] ? rcu_read_lock_sched_held+0x3a/0x70 [ 52.357489][ T3615] vfs_iter_write+0x70/0xa0 [ 52.361986][ T3615] iter_file_splice_write+0x718/0xc30 [ 52.367371][ T3615] ? splice_from_pipe_next.part.0+0x520/0x520 [ 52.373436][ T3615] ? security_file_permission+0xab/0xd0 [ 52.379062][ T3615] ? splice_from_pipe_next.part.0+0x520/0x520 [ 52.385146][ T3615] do_splice+0xb57/0x1920 [ 52.389477][ T3615] ? find_held_lock+0x2d/0x110 [ 52.394259][ T3615] ? splice_file_to_pipe+0x120/0x120 [ 52.399549][ T3615] ? lock_downgrade+0x6e0/0x6e0 [ 52.404396][ T3615] __do_splice+0x134/0x250 [ 52.408904][ T3615] ? do_splice+0x1920/0x1920 [ 52.413500][ T3615] __x64_sys_splice+0x198/0x250 [ 52.418345][ T3615] do_syscall_64+0x35/0xb0 [ 52.422770][ T3615] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 52.428663][ T3615] RIP: 0033:0x7f19d7c41c99 [ 52.433172][ T3615] 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 [ 52.452778][ T3615] RSP: 002b:00007f19d7bf4308 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 52.461702][ T3615] RAX: ffffffffffffffda RBX: 00007f19d7cca408 RCX: 00007f19d7c41c99 [pid 3615] <... splice resumed>) = ? [pid 3615] +++ exited with 0 +++ +++ exited with 0 +++ [ 52.469771][ T3615] RDX: 0000000000000006 RSI: 0000000000000000 RDI: 00