./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor1425050901 <...> forked to background, child pid 3184 no interfaces have a carrier [ 23.094326][ T3185] 8021q: adding VLAN 0 to HW filter on device bond0 [ 23.108366][ T3185] eql: remember to turn off Van-Jacobson compression on your slave devices Starting sshd: OK syzkaller Warning: Permanently added '10.128.0.71' (ECDSA) to the list of known hosts. execve("./syz-executor1425050901", ["./syz-executor1425050901"], 0x7ffcfd178500 /* 10 vars */) = 0 brk(NULL) = 0x5555572d7000 brk(0x5555572d7c40) = 0x5555572d7c40 arch_prctl(ARCH_SET_FS, 0x5555572d7300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 set_tid_address(0x5555572d75d0) = 3605 set_robust_list(0x5555572d75e0, 24) = 0 rt_sigaction(SIGRTMIN, {sa_handler=0x7f0f6c6d5c10, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f0f6c6d62e0}, NULL, 8) = 0 rt_sigaction(SIGRT_1, {sa_handler=0x7f0f6c6d5cb0, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f0f6c6d62e0}, 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-executor1425050901", 4096) = 28 brk(0x5555572f8c40) = 0x5555572f8c40 brk(0x5555572f9000) = 0x5555572f9000 mprotect(0x7f0f6c796000, 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(0x7f0f6c79c40c, FUTEX_WAKE_PRIVATE, 1000000) = 0 mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f0f6c6a6000 mprotect(0x7f0f6c6a7000, 131072, PROT_READ|PROT_WRITE) = 0 clone(child_stack=0x7f0f6c6c63f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[3606], tls=0x7f0f6c6c6700, child_tidptr=0x7f0f6c6c69d0) = 3606 futex(0x7f0f6c79c408, FUTEX_WAKE_PRIVATE, 1000000) = 0 futex(0x7f0f6c79c40c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000}./strace-static-x86_64: Process 3606 attached [pid 3606] set_robust_list(0x7f0f6c6c69e0, 24) = 0 [pid 3606] pipe([3, 4]) = 0 [pid 3606] futex(0x7f0f6c79c40c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3605] <... futex resumed>) = 0 [pid 3605] futex(0x7f0f6c79c408, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3605] futex(0x7f0f6c79c40c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3606] <... futex resumed>) = 1 [pid 3606] write(4, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"..., 4294966988 [pid 3605] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out) [pid 3605] futex(0x7f0f6c79c41c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3605] mmap(NULL, 135168, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_STACK, -1, 0) = 0x7f0f6c685000 [pid 3605] mprotect(0x7f0f6c686000, 131072, PROT_READ|PROT_WRITE) = 0 [pid 3605] clone(child_stack=0x7f0f6c6a53f0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tid=[3607], tls=0x7f0f6c6a5700, child_tidptr=0x7f0f6c6a59d0) = 3607 [pid 3605] futex(0x7f0f6c79c418, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3605] futex(0x7f0f6c79c41c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000}./strace-static-x86_64: Process 3607 attached [pid 3607] set_robust_list(0x7f0f6c6a59e0, 24) = 0 [pid 3607] pipe2([5, 6], O_EXCL) = 0 [pid 3607] futex(0x7f0f6c79c41c, FUTEX_WAKE_PRIVATE, 1000000 [pid 3605] <... futex resumed>) = 0 [pid 3605] futex(0x7f0f6c79c418, FUTEX_WAKE_PRIVATE, 1000000) = 0 [pid 3605] futex(0x7f0f6c79c41c, FUTEX_WAIT_PRIVATE, 0, {tv_sec=0, tv_nsec=50000000} [pid 3607] <... futex resumed>) = 1 syzkaller login: [ 39.481399][ T3607] [ 39.483785][ T3607] ============================================ [ 39.490109][ T3607] WARNING: possible recursive locking detected [ 39.496323][ T3607] 5.19.0-rc7-syzkaller-00007-g353f7988dd84 #0 Not tainted [ 39.503432][ T3607] -------------------------------------------- [ 39.509560][ T3607] syz-executor142/3607 is trying to acquire lock: [ 39.515958][ T3607] ffff88807d365c68 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x132/0x1bf0 [ 39.524743][ T3607] [ 39.524743][ T3607] but task is already holding lock: [ 39.532285][ T3607] ffff88807d366068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x5a/0x70 [ 39.540738][ T3607] [ 39.540738][ T3607] other info that might help us debug this: [ 39.548790][ T3607] Possible unsafe locking scenario: [ 39.548790][ T3607] [ 39.556228][ T3607] CPU0 [ 39.559589][ T3607] ---- [ 39.562856][ T3607] lock(&pipe->mutex/1); [ 39.567187][ T3607] lock(&pipe->mutex/1); [ 39.571512][ T3607] [ 39.571512][ T3607] *** DEADLOCK *** [ 39.571512][ T3607] [ 39.579729][ T3607] May be due to missing lock nesting notation [ 39.579729][ T3607] [ 39.588036][ T3607] 1 lock held by syz-executor142/3607: [ 39.593780][ T3607] #0: ffff88807d366068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x5a/0x70 [ 39.602752][ T3607] [ 39.602752][ T3607] stack backtrace: [ 39.608640][ T3607] CPU: 0 PID: 3607 Comm: syz-executor142 Not tainted 5.19.0-rc7-syzkaller-00007-g353f7988dd84 #0 [ 39.619319][ T3607] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 [ 39.629725][ T3607] Call Trace: [ 39.632997][ T3607] [ 39.635938][ T3607] dump_stack_lvl+0xcd/0x134 [ 39.640923][ T3607] __lock_acquire.cold+0x1f5/0x3b4 [ 39.646048][ T3607] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 39.652040][ T3607] ? __lock_acquire+0xbca/0x5660 [ 39.657073][ T3607] lock_acquire+0x1ab/0x570 [ 39.661576][ T3607] ? pipe_write+0x132/0x1bf0 [ 39.666428][ T3607] ? lock_release+0x780/0x780 [ 39.671127][ T3607] __mutex_lock+0x12f/0x1350 [ 39.675725][ T3607] ? pipe_write+0x132/0x1bf0 [ 39.680665][ T3607] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 39.686645][ T3607] ? lock_downgrade+0x6e0/0x6e0 [ 39.691497][ T3607] ? pipe_write+0x132/0x1bf0 [ 39.696262][ T3607] ? mutex_lock_io_nested+0x1190/0x1190 [ 39.701812][ T3607] ? find_held_lock+0x2d/0x110 [ 39.706582][ T3607] ? aa_file_perm+0x56b/0x1230 [ 39.711354][ T3607] ? lock_downgrade+0x6e0/0x6e0 [ 39.716233][ T3607] pipe_write+0x132/0x1bf0 [ 39.720661][ T3607] ? aa_file_perm+0x595/0x1230 [ 39.725421][ T3607] ? do_proc_dopipe_max_size_conv+0x1c0/0x1c0 [ 39.731485][ T3607] ? aa_path_link+0x2f0/0x2f0 [ 39.736156][ T3607] ? lock_release+0x780/0x780 [ 39.740818][ T3607] ? __kasan_kmalloc+0xa9/0xd0 [ 39.745579][ T3607] ? iter_file_splice_write+0x168/0xc70 [ 39.751116][ T3607] ? do_splice+0xb57/0x1920 [ 39.755790][ T3607] ? __do_splice+0x134/0x250 [ 39.760401][ T3607] do_iter_readv_writev+0x3d1/0x640 [ 39.765601][ T3607] ? new_sync_write+0x560/0x560 [ 39.770450][ T3607] ? bpf_lsm_file_permission+0x5/0x10 [ 39.775938][ T3607] ? security_file_permission+0xab/0xd0 [ 39.781778][ T3607] do_iter_write+0x182/0x700 [ 39.786378][ T3607] ? rcu_read_lock_sched_held+0x3a/0x70 [ 39.791931][ T3607] vfs_iter_write+0x70/0xa0 [ 39.796614][ T3607] iter_file_splice_write+0x723/0xc70 [ 39.801997][ T3607] ? page_cache_pipe_buf_confirm+0x5a0/0x5a0 [ 39.807980][ T3607] ? __lock_acquire+0xbca/0x5660 [ 39.812919][ T3607] ? bpf_lsm_file_permission+0x5/0x10 [ 39.818287][ T3607] ? security_file_permission+0xab/0xd0 [ 39.823857][ T3607] ? page_cache_pipe_buf_confirm+0x5a0/0x5a0 [ 39.829837][ T3607] do_splice+0xb57/0x1920 [ 39.834164][ T3607] ? find_held_lock+0x2d/0x110 [ 39.838926][ T3607] ? splice_file_to_pipe+0x120/0x120 [ 39.844224][ T3607] ? lock_downgrade+0x6e0/0x6e0 [ 39.849088][ T3607] __do_splice+0x134/0x250 [ 39.853505][ T3607] ? do_splice+0x1920/0x1920 [ 39.858095][ T3607] __x64_sys_splice+0x198/0x250 [ 39.862955][ T3607] do_syscall_64+0x35/0xb0 [ 39.867478][ T3607] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 39.873370][ T3607] RIP: 0033:0x7f0f6c713c79 [ 39.877800][ T3607] 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 [ 39.897504][ T3607] RSP: 002b:00007f0f6c6a5308 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 39.905914][ T3607] RAX: ffffffffffffffda RBX: 00007f0f6c79c418 RCX: 00007f0f6c713c79 [ 39.913900][ T3607] RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000003 [ 39.921868][ T3607] RBP: 00007f0f6c79c410 R08: 0000002000002001 R09: 0000000000000000 [pid 3607] splice(3, NULL, 6, NULL, 137438961665, 0 [pid 3605] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out) [pid 3607] <... splice resumed>) = -1 EXDEV (Invalid cross-device link) [pid 3607] futex(0x7f0f6c79c41c, FUTEX_WAKE_PRIVATE, 1000000) = 0 [ 39.929922][ T3607] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0f6c79c41c [ 39.938058][ T3607] R13: 00007fff26b411bf R14: 00007f0f6c6a5400 R15: 0000000000022000 [ 39.946024][ T3607] [pid 3607] futex(0x7f0f6c79c418, FUTEX_WAIT_PRIVATE, 0, NULL [pid 3605] exit_group(0) = ? [pid 3607] <... futex resumed>) = ? [pid 3606] <... write resumed>) = ? [pid 3607] +++ exited with 0 +++ [pid 3606] +++ exited with 0 +++ +++ exited with 0 +++