./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor3331825121 <...> DUID 00:04:e6:d8:3e:4c:c1:15:84:42:dc:00:60:8c:e3:5f:26:b4 forked to background, child pid 4645 [ 38.105690][ T4646] 8021q: adding VLAN 0 to HW filter on device bond0 [ 38.122546][ T4646] eql: remember to turn off Van-Jacobson compression on your slave devices Starting sshd: OK syzkaller Warning: Permanently added '10.128.0.253' (ECDSA) to the list of known hosts. execve("./syz-executor3331825121", ["./syz-executor3331825121"], 0x7fff126430e0 /* 10 vars */) = 0 brk(NULL) = 0x555555870000 brk(0x555555870c40) = 0x555555870c40 arch_prctl(ARCH_SET_FS, 0x555555870300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 readlink("/proc/self/exe", "/root/syz-executor3331825121", 4096) = 28 brk(0x555555891c40) = 0x555555891c40 brk(0x555555892000) = 0x555555892000 mprotect(0x7fd5196f0000, 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 unshare(CLONE_NEWPID) = 0 clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD./strace-static-x86_64: Process 5071 attached , child_tidptr=0x5555558705d0) = 5071 [pid 5071] mount(NULL, "/sys/fs/fuse/connections", "fusectl", 0, NULL) = -1 EBUSY (Device or resource busy) [pid 5071] prctl(PR_SET_PDEATHSIG, SIGKILL) = 0 [pid 5071] setsid() = 1 [pid 5071] prlimit64(0, RLIMIT_AS, {rlim_cur=204800*1024, rlim_max=204800*1024}, NULL) = 0 [pid 5071] prlimit64(0, RLIMIT_MEMLOCK, {rlim_cur=32768*1024, rlim_max=32768*1024}, NULL) = 0 [pid 5071] prlimit64(0, RLIMIT_FSIZE, {rlim_cur=139264*1024, rlim_max=139264*1024}, NULL) = 0 [pid 5071] prlimit64(0, RLIMIT_STACK, {rlim_cur=1024*1024, rlim_max=1024*1024}, NULL) = 0 [pid 5071] prlimit64(0, RLIMIT_CORE, {rlim_cur=131072*1024, rlim_max=131072*1024}, NULL) = 0 [pid 5071] prlimit64(0, RLIMIT_NOFILE, {rlim_cur=256, rlim_max=256}, NULL) = 0 [pid 5071] unshare(CLONE_NEWNS) = 0 [pid 5071] mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) = 0 [pid 5071] unshare(CLONE_NEWIPC) = 0 [pid 5071] unshare(CLONE_NEWCGROUP) = 0 [pid 5071] unshare(CLONE_NEWUTS) = 0 [pid 5071] unshare(CLONE_SYSVSEM) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/shmmax", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "16777216", 8) = 8 [pid 5071] close(3) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/shmall", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "536870912", 9) = 9 [pid 5071] close(3) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/shmmni", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "1024", 4) = 4 [pid 5071] close(3) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/msgmax", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "8192", 4) = 4 [pid 5071] close(3) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/msgmni", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "1024", 4) = 4 [pid 5071] close(3) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/msgmnb", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "1024", 4) = 4 [pid 5071] close(3) = 0 [pid 5071] openat(AT_FDCWD, "/proc/sys/kernel/sem", O_WRONLY|O_CLOEXEC) = 3 [pid 5071] write(3, "1024 1048576 500 1024", 21) = 21 [pid 5071] close(3) = 0 [pid 5071] getpid() = 1 [pid 5071] capget({version=_LINUX_CAPABILITY_VERSION_3, pid=1}, {effective=1<tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0 [ 57.899823][ T11] [ 57.899823][ T11] but task is already holding lock: [ 57.907190][ T11] ffff88807d3c40b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0 [ 57.917033][ T11] [ 57.917033][ T11] other info that might help us debug this: [ 57.925083][ T11] Possible unsafe locking scenario: [ 57.925083][ T11] [ 57.932558][ T11] CPU0 [ 57.935847][ T11] ---- [ 57.939120][ T11] lock(&tree->tree_lock/1); [ 57.943802][ T11] lock(&tree->tree_lock/1); [ 57.948482][ T11] [ 57.948482][ T11] *** DEADLOCK *** [ 57.948482][ T11] [ 57.956618][ T11] May be due to missing lock nesting notation [ 57.956618][ T11] [ 57.964927][ T11] 5 locks held by kworker/u4:1/11: [ 57.970028][ T11] #0: ffff888017813138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 [ 57.980650][ T11] #1: ffffc90000107d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 [ 57.992486][ T11] #2: ffff888027380108 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x8e/0x1f0 [ 58.003124][ T11] #3: ffff88807d3c40b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x14a/0x1c0 [ 58.013229][ T11] #4: ffff8880768b8108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1d6/0x1b10 [ 58.024740][ T11] [ 58.024740][ T11] stack backtrace: [ 58.030639][ T11] CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted 6.3.0-rc4-syzkaller-00199-g7b50567bdcad #0 [ 58.040609][ T11] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 [ 58.050751][ T11] Workqueue: writeback wb_workfn (flush-7:0) [ 58.056748][ T11] Call Trace: [ 58.060026][ T11] [ 58.062961][ T11] dump_stack_lvl+0x1e7/0x2d0 [ 58.067659][ T11] ? nf_tcp_handle_invalid+0x650/0x650 [ 58.073124][ T11] ? panic+0x770/0x770 [ 58.077202][ T11] validate_chain+0x472a/0x58e0 [ 58.082059][ T11] ? reacquire_held_locks+0x660/0x660 [ 58.087529][ T11] ? mark_lock+0x9a/0x340 [ 58.091859][ T11] ? lockdep_hardirqs_on_prepare+0x43c/0x7a0 [ 58.097836][ T11] ? mark_lock+0x9a/0x340 [ 58.102172][ T11] __lock_acquire+0x125b/0x1f80 [ 58.107029][ T11] lock_acquire+0x1e1/0x520 [ 58.111532][ T11] ? hfsplus_find_init+0x14a/0x1c0 [ 58.116651][ T11] ? read_lock_is_recursive+0x20/0x20 [ 58.122020][ T11] ? hfsplus_bmap_reserve+0x105/0x4e0 [ 58.127393][ T11] ? __hfsplus_ext_write_extent+0x2a4/0x5b0 [ 58.133293][ T11] ? __might_sleep+0xc0/0xc0 [ 58.137906][ T11] ? wb_writeback+0x458/0xc70 [ 58.142587][ T11] ? wb_workfn+0x400/0xff0 [ 58.147090][ T11] ? process_one_work+0x8a0/0x10e0 [ 58.152218][ T11] ? worker_thread+0xa63/0x1210 [ 58.157078][ T11] ? kthread+0x270/0x300 [ 58.161325][ T11] ? ret_from_fork+0x1f/0x30 [ 58.165945][ T11] __mutex_lock_common+0x1d8/0x2530 [ 58.171157][ T11] ? hfsplus_find_init+0x14a/0x1c0 [ 58.176293][ T11] ? hfsplus_find_init+0x14a/0x1c0 [ 58.181437][ T11] ? mutex_lock_io_nested+0x60/0x60 [ 58.186665][ T11] ? hfsplus_find_init+0x85/0x1c0 [ 58.191717][ T11] ? rcu_is_watching+0x15/0xb0 [ 58.196497][ T11] ? hfsplus_find_init+0x85/0x1c0 [ 58.201536][ T11] ? __kmalloc+0xe6/0x230 [ 58.205873][ T11] mutex_lock_nested+0x1b/0x20 [ 58.210653][ T11] hfsplus_find_init+0x14a/0x1c0 [ 58.215600][ T11] hfsplus_file_extend+0x40e/0x1b10 [ 58.220808][ T11] ? hfsplus_get_block+0x14e0/0x14e0 [ 58.226096][ T11] ? rcu_is_watching+0x15/0xb0 [ 58.230946][ T11] ? trace_contention_end+0x3c/0xf0 [ 58.236163][ T11] ? __mutex_lock_common+0x42d/0x2530 [ 58.241540][ T11] ? hfsplus_brec_find+0x19d/0x570 [ 58.246650][ T11] hfsplus_bmap_reserve+0x105/0x4e0 [ 58.251861][ T11] __hfsplus_ext_write_extent+0x2a4/0x5b0 [ 58.257604][ T11] hfsplus_ext_write_extent+0x16a/0x1f0 [ 58.263170][ T11] ? hfsplus_ext_cmp_key+0x2f0/0x2f0 [ 58.268470][ T11] ? do_raw_spin_lock+0x14d/0x3a0 [ 58.273571][ T11] hfsplus_write_inode+0x22/0x5e0 [ 58.278626][ T11] __writeback_single_inode+0x69b/0xfb0 [ 58.284222][ T11] writeback_sb_inodes+0x8ef/0x11d0 [ 58.289462][ T11] ? queue_io+0x570/0x570 [ 58.293799][ T11] ? __writeback_inodes_wb+0x260/0x260 [ 58.299290][ T11] ? queue_io+0x3d5/0x570 [ 58.304682][ T11] wb_writeback+0x458/0xc70 [ 58.309204][ T11] ? rcu_lock_release+0x30/0x30 [ 58.314248][ T11] ? lockdep_hardirqs_on_prepare+0x43c/0x7a0 [ 58.320249][ T11] wb_workfn+0x400/0xff0 [ 58.324556][ T11] ? inode_wait_for_writeback+0x290/0x290 [ 58.330292][ T11] ? read_lock_is_recursive+0x20/0x20 [ 58.335769][ T11] ? lockdep_hardirqs_on_prepare+0x43c/0x7a0 [ 58.341752][ T11] ? print_irqtrace_events+0x220/0x220 [ 58.347260][ T11] ? _raw_spin_unlock_irqrestore+0xdd/0x140 [ 58.353167][ T11] process_one_work+0x8a0/0x10e0 [ 58.358112][ T11] ? worker_detach_from_pool+0x290/0x290 [ 58.363747][ T11] ? _raw_spin_lock_irqsave+0x120/0x120 [ 58.369468][ T11] ? kthread_data+0x52/0xc0 [ 58.373977][ T11] ? wq_worker_running+0x9b/0x1a0 [ 58.379002][ T11] worker_thread+0xa63/0x1210 [ 58.383693][ T11] kthread+0x270/0x300 [ 58.387759][ T11] ? pr_cont_work+0x5e0/0x5e0 [ 58.392449][ T11] ? kthread_blkcg+0xd0/0xd0 [ 58.397035][ T11] ret_from_fork+0x1f/0x30 [ 58.401470][ T11]