./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor3929375974 <...> Warning: Permanently added '10.128.1.37' (ECDSA) to the list of known hosts. execve("./syz-executor3929375974", ["./syz-executor3929375974"], 0x7ffc6866f530 /* 10 vars */) = 0 brk(NULL) = 0x5555555f4000 brk(0x5555555f4c40) = 0x5555555f4c40 arch_prctl(ARCH_SET_FS, 0x5555555f4300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 set_tid_address(0x5555555f45d0) = 3613 set_robust_list(0x5555555f45e0, 24) = 0 rt_sigaction(SIGRTMIN, {sa_handler=0x7f9fefd72c30, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f9fefd73300}, NULL, 8) = 0 rt_sigaction(SIGRT_1, {sa_handler=0x7f9fefd72cd0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f9fefd73300}, 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-executor3929375974", 4096) = 28 brk(0x555555615c40) = 0x555555615c40 brk(0x555555616000) = 0x555555616000 mprotect(0x7f9fefe33000, 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(0x7f9fefe3940c, FUTEX_WAKE_PRIVATE, 1000000) = 0 mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f9fefd43000 mprotect(0x7f9fefd44000, 131072, PROT_READ|PROT_WRITE) = 0 clone(child_stack=0x7f9fefd633f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[3614], tls=0x7f9fefd63700, child_tidptr=0x7f9fefd639d0) = 3614 futex(0x7f9fefe39408, FUTEX_WAKE_PRIVATE, 1000000) = 0 futex(0x7f9fefe3940c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000}./strace-static-x86_64: Process 3614 attached [pid 3614] set_robust_list(0x7f9fefd639e0, 24) = 0 [pid 3614] pipe([3, 4]) = 0 [pid 3614] futex(0x7f9fefe3940c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3613] <... futex resumed>) = 0 [pid 3613] futex(0x7f9fefe39408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3613] futex(0x7f9fefe3940c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3614] <... futex resumed>) = 1 [pid 3614] pipe2([5, 6], O_EXCL) = 0 [pid 3614] futex(0x7f9fefe3940c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3613] <... futex resumed>) = 0 [pid 3613] futex(0x7f9fefe39408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3613] futex(0x7f9fefe3940c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3614] <... futex resumed>) = 1 [pid 3614] splice(3, NULL, 6, NULL, 511, 0 [pid 3613] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out) [pid 3613] futex(0x7f9fefe3941c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3613] mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f9fefd22000 [pid 3613] mprotect(0x7f9fefd23000, 131072, PROT_READ|PROT_WRITE) = 0 [pid 3613] clone(child_stack=0x7f9fefd423f0, 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 3615 attached , parent_tid=[3615], tls=0x7f9fefd42700, child_tidptr=0x7f9fefd429d0) = 3615 [pid 3613] futex(0x7f9fefe39418, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3613] futex(0x7f9fefe3941c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3615] set_robust_list(0x7f9fefd429e0, 24) = 0 [pid 3615] vmsplice(4, [{iov_base="\xb5", iov_len=1}], 1, 0) = 1 [ 51.382121][ T27] audit: type=1400 audit(1660837184.604:75): avc: denied { execmem } for pid=3613 comm="syz-executor392" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [pid 3615] futex(0x7f9fefe3941c, FUTEX_WAKE_PRIVATE, 1000000) = 1 [pid 3615] futex(0x7f9fefe39418, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3613] <... futex resumed>) = 0 [ 51.439305][ T3614] [ 51.441687][ T3614] ============================================ [ 51.447840][ T3614] WARNING: possible recursive locking detected [ 51.453994][ T3614] 6.0.0-rc1-syzkaller-00025-g274a2eebf80c #0 Not tainted [ 51.461001][ T3614] -------------------------------------------- [ 51.467139][ T3614] syz-executor392/3614 is trying to acquire lock: [ 51.473544][ T3614] ffff888028310868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x132/0x1be0 [ 51.482358][ T3614] [ 51.482358][ T3614] but task is already holding lock: [ 51.489720][ T3614] ffff888028310468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 51.499122][ T3614] [ 51.499122][ T3614] other info that might help us debug this: [ 51.507171][ T3614] Possible unsafe locking scenario: [ 51.507171][ T3614] [ 51.514609][ T3614] CPU0 [ 51.517887][ T3614] ---- [ 51.521155][ T3614] lock(&pipe->mutex/1); [ 51.525484][ T3614] lock(&pipe->mutex/1); [ 51.529815][ T3614] [ 51.529815][ T3614] *** DEADLOCK *** [ 51.529815][ T3614] [ 51.537957][ T3614] May be due to missing lock nesting notation [ 51.537957][ T3614] [ 51.546267][ T3614] 1 lock held by syz-executor392/3614: [ 51.551719][ T3614] #0: ffff888028310468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x39b/0x420 [ 51.561674][ T3614] [ 51.561674][ T3614] stack backtrace: [ 51.567578][ T3614] CPU: 1 PID: 3614 Comm: syz-executor392 Not tainted 6.0.0-rc1-syzkaller-00025-g274a2eebf80c #0 [ 51.577986][ T3614] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 [ 51.588037][ T3614] Call Trace: [ 51.591321][ T3614] [ 51.594269][ T3614] dump_stack_lvl+0xcd/0x134 [ 51.598967][ T3614] __lock_acquire.cold+0x116/0x3a7 [ 51.604087][ T3614] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 51.610071][ T3614] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 51.616052][ T3614] lock_acquire+0x1ab/0x570 [ 51.620558][ T3614] ? pipe_write+0x132/0x1be0 [ 51.625148][ T3614] ? lock_release+0x780/0x780 [ 51.629821][ T3614] __mutex_lock+0x12f/0x1350 [ 51.634424][ T3614] ? pipe_write+0x132/0x1be0 [ 51.639023][ T3614] ? avc_has_perm_noaudit+0x1f0/0x390 [ 51.644396][ T3614] ? pipe_write+0x132/0x1be0 [ 51.648991][ T3614] ? mutex_lock_io_nested+0x1190/0x1190 [ 51.654540][ T3614] ? lock_release+0x780/0x780 [ 51.659218][ T3614] pipe_write+0x132/0x1be0 [ 51.663649][ T3614] ? avc_has_perm_noaudit+0x390/0x390 [ 51.669019][ T3614] ? trace_contention_end+0xea/0x150 [ 51.674311][ T3614] ? __mutex_lock+0x231/0x1350 [ 51.679078][ T3614] ? do_proc_dopipe_max_size_conv+0x1c0/0x1c0 [ 51.685163][ T3614] ? file_has_perm+0x25a/0x340 [ 51.689928][ T3614] ? selinux_bprm_committing_creds+0x6f0/0x6f0 [ 51.696083][ T3614] do_iter_readv_writev+0x20b/0x3b0 [ 51.701285][ T3614] ? generic_copy_file_range+0xd0/0xd0 [ 51.706747][ T3614] ? security_file_permission+0xab/0xd0 [ 51.712291][ T3614] do_iter_write+0x182/0x700 [ 51.716885][ T3614] ? rcu_read_lock_sched_held+0x3a/0x70 [ 51.722441][ T3614] vfs_iter_write+0x70/0xa0 [ 51.726944][ T3614] iter_file_splice_write+0x718/0xc30 [ 51.732513][ T3614] ? splice_from_pipe_next.part.0+0x520/0x520 [ 51.738594][ T3614] ? security_file_permission+0xab/0xd0 [ 51.744422][ T3614] ? splice_from_pipe_next.part.0+0x520/0x520 [ 51.750492][ T3614] do_splice+0xb57/0x1920 [ 51.754827][ T3614] ? find_held_lock+0x2d/0x110 [ 51.759593][ T3614] ? splice_file_to_pipe+0x120/0x120 [ 51.764879][ T3614] ? lock_downgrade+0x6e0/0x6e0 [ 51.769730][ T3614] __do_splice+0x134/0x250 [ 51.774147][ T3614] ? do_splice+0x1920/0x1920 [ 51.778739][ T3614] __x64_sys_splice+0x198/0x250 [ 51.783613][ T3614] do_syscall_64+0x35/0xb0 [ 51.788035][ T3614] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 51.793935][ T3614] RIP: 0033:0x7f9fefdb0c99 [ 51.798363][ T3614] 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 [ 51.817969][ T3614] RSP: 002b:00007f9fefd63308 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 51.826382][ T3614] RAX: ffffffffffffffda RBX: 00007f9fefe39408 RCX: 00007f9fefdb0c99 [pid 3614] <... splice resumed>) = -1 EXDEV (Invalid cross-device link) [pid 3614] futex(0x7f9fefe3940c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3614] futex(0x7f9fefe39408, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3613] exit_group(0) = ? [pid 3615] <... futex resumed>) = ? [pid 3615] +++ exited with 0 +++ [pid 3614] <... futex resumed>) = ? [pid 3614] +++ exited with 0 +++ +++ exited with 0 +++ [ 51.834349][ T3614] RDX: 0000000000000006 RSI: 0000000000000000 RDI: 00000000