./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor1250694568 <...> Warning: Permanently added '10.128.1.76' (ECDSA) to the list of known hosts. execve("./syz-executor1250694568", ["./syz-executor1250694568"], 0x7ffd49e54a60 /* 10 vars */) = 0 brk(NULL) = 0x555555c67000 brk(0x555555c67c40) = 0x555555c67c40 arch_prctl(ARCH_SET_FS, 0x555555c67300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 set_tid_address(0x555555c675d0) = 3601 set_robust_list(0x555555c675e0, 24) = 0 rt_sigaction(SIGRTMIN, {sa_handler=0x7f78cdfacc30, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f78cdfad300}, NULL, 8) = 0 rt_sigaction(SIGRT_1, {sa_handler=0x7f78cdfaccd0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f78cdfad300}, 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-executor1250694568", 4096) = 28 brk(0x555555c88c40) = 0x555555c88c40 brk(0x555555c89000) = 0x555555c89000 mprotect(0x7f78ce06d000, 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(0x7f78ce07340c, FUTEX_WAKE_PRIVATE, 1000000) = 0 mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f78cdf7d000 mprotect(0x7f78cdf7e000, 131072, PROT_READ|PROT_WRITE) = 0 clone(child_stack=0x7f78cdf9d3f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[3602], tls=0x7f78cdf9d700, child_tidptr=0x7f78cdf9d9d0) = 3602 futex(0x7f78ce073408, FUTEX_WAKE_PRIVATE, 1000000) = 0 futex(0x7f78ce07340c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000}./strace-static-x86_64: Process 3602 attached [pid 3602] set_robust_list(0x7f78cdf9d9e0, 24) = 0 [pid 3602] pipe([3, 4]) = 0 [pid 3602] futex(0x7f78ce07340c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3601] <... futex resumed>) = 0 [pid 3601] futex(0x7f78ce073408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3601] futex(0x7f78ce07340c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3602] <... futex resumed>) = 1 [pid 3602] pipe2([5, 6], O_EXCL) = 0 [pid 3602] futex(0x7f78ce07340c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3601] <... futex resumed>) = 0 [pid 3601] futex(0x7f78ce073408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3601] futex(0x7f78ce07340c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3602] <... futex resumed>) = 1 [pid 3602] splice(3, NULL, 6, NULL, 511, 0 [pid 3601] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out) [pid 3601] futex(0x7f78ce07341c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3601] mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f78cdf5c000 [pid 3601] mprotect(0x7f78cdf5d000, 131072, PROT_READ|PROT_WRITE) = 0 [pid 3601] clone(child_stack=0x7f78cdf7c3f0, 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 3603 attached , parent_tid=[3603], tls=0x7f78cdf7c700, child_tidptr=0x7f78cdf7c9d0) = 3603 [pid 3601] futex(0x7f78ce073418, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3601] futex(0x7f78ce07341c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3603] set_robust_list(0x7f78cdf7c9e0, 24) = 0 [pid 3603] vmsplice(4, [{iov_base="\xb5", iov_len=1}], 1, 0) = 1 [pid 3603] futex(0x7f78ce07341c, FUTEX_WAKE_PRIVATE, 1000000) = 1 [pid 3603] futex(0x7f78ce073418, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3601] <... futex resumed>) = 0 syzkaller login: [ 51.510350][ T3602] [ 51.512715][ T3602] ============================================ [ 51.518864][ T3602] WARNING: possible recursive locking detected [ 51.525092][ T3602] 5.19.0-rc4-next-20220628-syzkaller #0 Not tainted [ 51.531674][ T3602] -------------------------------------------- [ 51.537999][ T3602] syz-executor125/3602 is trying to acquire lock: [ 51.544407][ T3602] ffff8880783e8468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x132/0x1bf0 [ 51.553191][ T3602] [ 51.553191][ T3602] but task is already holding lock: [ 51.560544][ T3602] ffff8880783e8868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 51.569941][ T3602] [ 51.569941][ T3602] other info that might help us debug this: [ 51.577996][ T3602] Possible unsafe locking scenario: [ 51.577996][ T3602] [ 51.585438][ T3602] CPU0 [ 51.588711][ T3602] ---- [ 51.591988][ T3602] lock(&pipe->mutex/1); [ 51.596323][ T3602] lock(&pipe->mutex/1); [ 51.600652][ T3602] [ 51.600652][ T3602] *** DEADLOCK *** [ 51.600652][ T3602] [ 51.608785][ T3602] May be due to missing lock nesting notation [ 51.608785][ T3602] [ 51.617091][ T3602] 1 lock held by syz-executor125/3602: [ 51.622538][ T3602] #0: ffff8880783e8868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 51.632379][ T3602] [ 51.632379][ T3602] stack backtrace: [ 51.638255][ T3602] CPU: 1 PID: 3602 Comm: syz-executor125 Not tainted 5.19.0-rc4-next-20220628-syzkaller #0 [ 51.648240][ T3602] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 [ 51.658288][ T3602] Call Trace: [ 51.661563][ T3602] [ 51.664493][ T3602] dump_stack_lvl+0xcd/0x134 [ 51.669114][ T3602] __lock_acquire.cold+0x1f5/0x3b4 [ 51.674230][ T3602] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 51.680229][ T3602] lock_acquire+0x1ab/0x570 [ 51.684727][ T3602] ? pipe_write+0x132/0x1bf0 [ 51.689318][ T3602] ? lock_release+0x780/0x780 [ 51.694003][ T3602] __mutex_lock+0x12f/0x1350 [ 51.698595][ T3602] ? pipe_write+0x132/0x1bf0 [ 51.703183][ T3602] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 51.709250][ T3602] ? pipe_write+0x132/0x1bf0 [ 51.713839][ T3602] ? mutex_lock_io_nested+0x1190/0x1190 [ 51.719390][ T3602] ? find_held_lock+0x2d/0x110 [ 51.724169][ T3602] ? aa_file_perm+0x56b/0x1230 [ 51.728937][ T3602] ? lock_downgrade+0x6e0/0x6e0 [ 51.733791][ T3602] pipe_write+0x132/0x1bf0 [ 51.738208][ T3602] ? aa_file_perm+0x595/0x1230 [ 51.742980][ T3602] ? do_proc_dopipe_max_size_conv+0x1c0/0x1c0 [ 51.749047][ T3602] ? aa_path_link+0x2f0/0x2f0 [ 51.753729][ T3602] ? mutex_lock_io_nested+0x1190/0x1190 [ 51.759288][ T3602] ? pipe_wait_readable+0x336/0x420 [ 51.764509][ T3602] ? lock_downgrade+0x6e0/0x6e0 [ 51.769373][ T3602] do_iter_readv_writev+0x360/0x5c0 [ 51.774572][ T3602] ? ksys_lseek+0x1b0/0x1b0 [ 51.779073][ T3602] ? bpf_lsm_file_permission+0x5/0x10 [ 51.784486][ T3602] ? security_file_permission+0xab/0xd0 [ 51.790036][ T3602] do_iter_write+0x182/0x700 [ 51.794662][ T3602] vfs_iter_write+0x70/0xa0 [ 51.799160][ T3602] iter_file_splice_write+0x723/0xc70 [ 51.804542][ T3602] ? page_cache_pipe_buf_confirm+0x5b0/0x5b0 [ 51.810528][ T3602] ? __lock_acquire+0xbca/0x5660 [ 51.815468][ T3602] ? bpf_lsm_file_permission+0x5/0x10 [ 51.820846][ T3602] ? security_file_permission+0xab/0xd0 [ 51.826396][ T3602] ? page_cache_pipe_buf_confirm+0x5b0/0x5b0 [ 51.832384][ T3602] do_splice+0xb57/0x1920 [ 51.836715][ T3602] ? find_held_lock+0x2d/0x110 [ 51.841485][ T3602] ? splice_file_to_pipe+0x120/0x120 [ 51.846766][ T3602] ? lock_downgrade+0x6e0/0x6e0 [ 51.851616][ T3602] __do_splice+0x134/0x250 [ 51.856042][ T3602] ? do_splice+0x1920/0x1920 [ 51.860629][ T3602] __x64_sys_splice+0x198/0x250 [ 51.865476][ T3602] do_syscall_64+0x35/0xb0 [ 51.869894][ T3602] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 51.875787][ T3602] RIP: 0033:0x7f78cdfeac99 [ 51.880199][ T3602] 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 [ 51.899801][ T3602] RSP: 002b:00007f78cdf9d308 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [pid 3602] <... splice resumed>) = -1 EXDEV (Invalid cross-device link) [pid 3602] futex(0x7f78ce07340c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3602] futex(0x7f78ce073408, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3601] exit_group(0) = ? [pid 3602] <... futex resumed>) = ? [pid 3603] <... futex resumed>) = ? [pid 3603] +++ exited with 0 +++ [pid 3602] +++ exited with 0 +++ +++ exited with 0 +++ [ 51.908210][ T3602] RAX: ffffffffffffffda