./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor4101881827 <...> Warning: Permanently added '10.128.1.173' (ECDSA) to the list of known hosts. execve("./syz-executor4101881827", ["./syz-executor4101881827"], 0x7ffe6dd868a0 /* 10 vars */) = 0 brk(NULL) = 0x555555757000 brk(0x555555757c40) = 0x555555757c40 arch_prctl(ARCH_SET_FS, 0x555555757300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 readlink("/proc/self/exe", "/root/syz-executor4101881827", 4096) = 28 brk(0x555555778c40) = 0x555555778c40 brk(0x555555779000) = 0x555555779000 mprotect(0x7fb8ca759000, 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 5004 attached , child_tidptr=0x5555557575d0) = 5004 [pid 5004] mount(NULL, "/sys/fs/fuse/connections", "fusectl", 0, NULL) = -1 EBUSY (Device or resource busy) [pid 5004] prctl(PR_SET_PDEATHSIG, SIGKILL) = 0 [pid 5004] setsid() = 1 [pid 5004] prlimit64(0, RLIMIT_AS, {rlim_cur=204800*1024, rlim_max=204800*1024}, NULL) = 0 [pid 5004] prlimit64(0, RLIMIT_MEMLOCK, {rlim_cur=32768*1024, rlim_max=32768*1024}, NULL) = 0 [pid 5004] prlimit64(0, RLIMIT_FSIZE, {rlim_cur=139264*1024, rlim_max=139264*1024}, NULL) = 0 [pid 5004] prlimit64(0, RLIMIT_STACK, {rlim_cur=1024*1024, rlim_max=1024*1024}, NULL) = 0 [pid 5004] prlimit64(0, RLIMIT_CORE, {rlim_cur=131072*1024, rlim_max=131072*1024}, NULL) = 0 [pid 5004] prlimit64(0, RLIMIT_NOFILE, {rlim_cur=256, rlim_max=256}, NULL) = 0 [pid 5004] unshare(CLONE_NEWNS) = 0 [pid 5004] mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) = 0 [pid 5004] unshare(CLONE_NEWIPC) = 0 [pid 5004] unshare(CLONE_NEWCGROUP) = 0 [pid 5004] unshare(CLONE_NEWUTS) = 0 [pid 5004] unshare(CLONE_SYSVSEM) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/shmmax", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "16777216", 8) = 8 [pid 5004] close(3) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/shmall", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "536870912", 9) = 9 [pid 5004] close(3) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/shmmni", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "1024", 4) = 4 [pid 5004] close(3) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/msgmax", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "8192", 4) = 4 [pid 5004] close(3) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/msgmni", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "1024", 4) = 4 [pid 5004] close(3) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/msgmnb", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "1024", 4) = 4 [pid 5004] close(3) = 0 [pid 5004] openat(AT_FDCWD, "/proc/sys/kernel/sem", O_WRONLY|O_CLOEXEC) = 3 [pid 5004] write(3, "1024 1048576 500 1024", 21) = 21 [pid 5004] close(3) = 0 [pid 5004] getpid() = 1 [pid 5004] capget({version=_LINUX_CAPABILITY_VERSION_3, pid=1}, {effective=1<tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x174/0x230 [ 43.642931][ T52] [ 43.642931][ T52] but task is already holding lock: [ 43.650265][ T52] ffff88807c4300b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x174/0x230 [ 43.659894][ T52] [ 43.659894][ T52] other info that might help us debug this: [ 43.667927][ T52] Possible unsafe locking scenario: [ 43.667927][ T52] [ 43.675360][ T52] CPU0 [ 43.678619][ T52] ---- [ 43.681876][ T52] lock(&tree->tree_lock/1); [ 43.686542][ T52] lock(&tree->tree_lock/1); [ 43.691229][ T52] [ 43.691229][ T52] *** DEADLOCK *** [ 43.691229][ T52] [ 43.699351][ T52] May be due to missing lock nesting notation [ 43.699351][ T52] [ 43.707689][ T52] 5 locks held by kworker/u4:3/52: [ 43.712784][ T52] #0: ffff888012ecb138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x883/0x15e0 [ 43.723393][ T52] #1: ffffc90000bd7db0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x15e0 [ 43.735212][ T52] #2: ffff88807c41a988 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x82/0x200 [ 43.745812][ T52] #3: ffff88807c4300b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x174/0x230 [ 43.755897][ T52] #4: ffff88807c418108 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1bf/0xf90 [ 43.767274][ T52] [ 43.767274][ T52] stack backtrace: [ 43.773141][ T52] CPU: 1 PID: 52 Comm: kworker/u4:3 Not tainted 6.4.0-rc6-syzkaller-00006-gfd37b884003c #0 [ 43.783101][ T52] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 [ 43.793140][ T52] Workqueue: writeback wb_workfn (flush-7:0) [ 43.799171][ T52] Call Trace: [ 43.802455][ T52] [ 43.805369][ T52] dump_stack_lvl+0xd9/0x150 [ 43.809954][ T52] __lock_acquire+0x13eb/0x5f30 [ 43.814818][ T52] ? lockdep_hardirqs_on+0x7d/0x100 [ 43.820032][ T52] ? lockdep_hardirqs_on_prepare+0x410/0x410 [ 43.826021][ T52] ? __stack_depot_save+0x23b/0x510 [ 43.831233][ T52] lock_acquire+0x1b1/0x520 [ 43.835733][ T52] ? hfsplus_find_init+0x174/0x230 [ 43.840842][ T52] ? lock_sync+0x190/0x190 [ 43.845274][ T52] ? wb_writeback+0x294/0xa50 [ 43.849944][ T52] ? wb_workfn+0x2a5/0xfc0 [ 43.854357][ T52] __mutex_lock+0x12f/0x1350 [ 43.858956][ T52] ? hfsplus_find_init+0x174/0x230 [ 43.864060][ T52] ? __kmem_cache_alloc_node+0x48/0x320 [ 43.869597][ T52] ? hfsplus_find_init+0x174/0x230 [ 43.874702][ T52] ? mutex_lock_io_nested+0x11a0/0x11a0 [ 43.880239][ T52] ? __kmem_cache_alloc_node+0x1b0/0x320 [ 43.885892][ T52] ? hfsplus_find_init+0x95/0x230 [ 43.890924][ T52] ? rcu_is_watching+0x12/0xb0 [ 43.895692][ T52] hfsplus_find_init+0x174/0x230 [ 43.900629][ T52] hfsplus_ext_read_extent+0x185/0xae0 [ 43.906115][ T52] ? mutex_lock_io_nested+0x11a0/0x11a0 [ 43.911665][ T52] ? _raw_spin_unlock+0x28/0x40 [ 43.916515][ T52] ? hfsplus_free_extents+0x510/0x510 [ 43.921885][ T52] ? hfsplus_block_allocate+0x7e/0x8c0 [ 43.927343][ T52] ? rcu_is_watching+0x12/0xb0 [ 43.932103][ T52] ? __mark_inode_dirty+0x297/0xd60 [ 43.937300][ T52] hfsplus_file_extend+0x684/0xf90 [ 43.942412][ T52] ? hfsplus_free_fork+0x7d0/0x7d0 [ 43.947513][ T52] ? __mutex_lock+0x231/0x1350 [ 43.952262][ T52] ? hfsplus_find_init+0x174/0x230 [ 43.957369][ T52] ? hfsplus_brec_find+0x3ee/0x520 [ 43.962478][ T52] ? hfsplus_brec_remove+0x4f0/0x4f0 [ 43.967758][ T52] hfsplus_bmap_reserve+0x31c/0x410 [ 43.972948][ T52] __hfsplus_ext_write_extent+0x44b/0x5b0 [ 43.978658][ T52] hfsplus_ext_write_extent+0x1ba/0x200 [ 43.984199][ T52] ? hfsplus_ext_cmp_key+0x300/0x300 [ 43.989477][ T52] ? __writeback_single_inode+0x2e4/0xdb0 [ 43.995190][ T52] ? lock_downgrade+0x690/0x690 [ 44.000120][ T52] ? do_raw_spin_lock+0x124/0x2b0 [ 44.005147][ T52] hfsplus_write_inode+0x22/0x520 [ 44.010165][ T52] __writeback_single_inode+0x9f2/0xdb0 [ 44.015705][ T52] writeback_sb_inodes+0x54d/0xe70 [ 44.020811][ T52] ? sync_inode_metadata+0xe0/0xe0 [ 44.025919][ T52] ? rcu_is_watching+0x12/0xb0 [ 44.030679][ T52] ? queue_io+0x386/0x4e0 [ 44.035004][ T52] wb_writeback+0x294/0xa50 [ 44.039503][ T52] ? __writeback_inodes_wb+0x280/0x280 [ 44.045125][ T52] ? lock_downgrade+0x690/0x690 [ 44.049968][ T52] ? mark_held_locks+0x9f/0xe0 [ 44.054721][ T52] ? _raw_spin_unlock_irq+0x23/0x50 [ 44.059922][ T52] wb_workfn+0x2a5/0xfc0 [ 44.064160][ T52] ? inode_wait_for_writeback+0x40/0x40 [ 44.069700][ T52] ? lock_sync+0x190/0x190 [ 44.074104][ T52] ? lock_downgrade+0x690/0x690 [ 44.078947][ T52] ? _raw_spin_unlock_irq+0x23/0x50 [ 44.084138][ T52] process_one_work+0x99a/0x15e0 [ 44.089068][ T52] ? pwq_dec_nr_in_flight+0x2a0/0x2a0 [ 44.094433][ T52] ? spin_bug+0x1c0/0x1c0 [ 44.098752][ T52] ? _raw_spin_lock_irq+0x45/0x50 [ 44.103770][ T52] worker_thread+0x67d/0x10c0 [ 44.108471][ T52] ? process_one_work+0x15e0/0x15e0 [ 44.113661][ T52] kthread+0x344/0x440 [ 44.117721][ T52] ? kthread_complete_and_exit+0x40/0x40 [ 44.123432][ T52] ret_from_fork+0x1f/0x30 [ 44.127846][ T52]