./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor47792490 <...> Warning: Permanently added '10.128.1.171' (ED25519) to the list of known hosts. execve("./syz-executor47792490", ["./syz-executor47792490"], 0x7ffe504276a0 /* 10 vars */) = 0 brk(NULL) = 0x55555671b000 brk(0x55555671bd00) = 0x55555671bd00 arch_prctl(ARCH_SET_FS, 0x55555671b380) = 0 set_tid_address(0x55555671b650) = 5062 set_robust_list(0x55555671b660, 24) = 0 rseq(0x55555671bca0, 0x20, 0, 0x53053053) = 0 prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0 readlink("/proc/self/exe", "/root/syz-executor47792490", 4096) = 26 getrandom("\xe3\xb1\x11\xfc\xef\x65\xec\xa2", 8, GRND_NONBLOCK) = 8 brk(NULL) = 0x55555671bd00 brk(0x55555673cd00) = 0x55555673cd00 brk(0x55555673d000) = 0x55555673d000 mprotect(0x7f640b3ea000, 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, child_tidptr=0x55555671b650) = 5063 ./strace-static-x86_64: Process 5063 attached [pid 5063] set_robust_list(0x55555671b660, 24) = 0 [ 76.235909][ T27] audit: type=1400 audit(1701659123.607:83): avc: denied { execmem } for pid=5062 comm="syz-executor477" scontext=root:sysadm_r:sysadm_t tcontext=root:sysadm_r:sysadm_t tclass=process permissive=1 [pid 5063] mount(NULL, "/sys/fs/fuse/connections", "fusectl", 0, NULL) = -1 EBUSY (Device or resource busy) [pid 5063] prctl(PR_SET_PDEATHSIG, SIGKILL) = 0 [pid 5063] setsid() = 1 [pid 5063] prlimit64(0, RLIMIT_AS, {rlim_cur=204800*1024, rlim_max=204800*1024}, NULL) = 0 [pid 5063] prlimit64(0, RLIMIT_MEMLOCK, {rlim_cur=32768*1024, rlim_max=32768*1024}, NULL) = 0 [pid 5063] prlimit64(0, RLIMIT_FSIZE, {rlim_cur=139264*1024, rlim_max=139264*1024}, NULL) = 0 [pid 5063] prlimit64(0, RLIMIT_STACK, {rlim_cur=1024*1024, rlim_max=1024*1024}, NULL) = 0 [pid 5063] prlimit64(0, RLIMIT_CORE, {rlim_cur=131072*1024, rlim_max=131072*1024}, NULL) = 0 [pid 5063] prlimit64(0, RLIMIT_NOFILE, {rlim_cur=256, rlim_max=256}, NULL) = 0 [pid 5063] unshare(CLONE_NEWNS) = 0 [ 76.296649][ T27] audit: type=1400 audit(1701659123.667:84): avc: denied { mounton } for pid=5063 comm="syz-executor477" path="/sys/fs/fuse/connections" dev="fusectl" ino=1 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:fusefs_t tclass=dir permissive=1 [ 76.320865][ T27] audit: type=1400 audit(1701659123.667:85): avc: denied { mount } for pid=5063 comm="syz-executor477" name="/" dev="fusectl" ino=1 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:fusefs_t tclass=filesystem permissive=1 [pid 5063] mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) = 0 [pid 5063] unshare(CLONE_NEWIPC) = 0 [pid 5063] unshare(CLONE_NEWCGROUP) = 0 [pid 5063] unshare(CLONE_NEWUTS) = 0 [pid 5063] unshare(CLONE_SYSVSEM) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/shmmax", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "16777216", 8) = 8 [ 76.368004][ T27] audit: type=1400 audit(1701659123.737:86): avc: denied { mounton } for pid=5063 comm="syz-executor477" path="/" dev="sda1" ino=2 scontext=root:sysadm_r:sysadm_t tcontext=system_u:object_r:root_t tclass=dir permissive=1 [pid 5063] close(3) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/shmall", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "536870912", 9) = 9 [pid 5063] close(3) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/shmmni", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "1024", 4) = 4 [pid 5063] close(3) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/msgmax", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "8192", 4) = 4 [pid 5063] close(3) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/msgmni", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "1024", 4) = 4 [pid 5063] close(3) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/msgmnb", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "1024", 4) = 4 [pid 5063] close(3) = 0 [pid 5063] openat(AT_FDCWD, "/proc/sys/kernel/sem", O_WRONLY|O_CLOEXEC) = 3 [pid 5063] write(3, "1024 1048576 500 1024", 21) = 21 [pid 5063] close(3) = 0 [pid 5063] getpid() = 1 [pid 5063] capget({version=_LINUX_CAPABILITY_VERSION_3, pid=1}, {effective=1<tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x16e/0x200 [ 76.954591][ T2404] [ 76.954591][ T2404] but task is already holding lock: [ 76.961941][ T2404] ffff88801c8da0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x16e/0x200 [ 76.971602][ T2404] [ 76.971602][ T2404] other info that might help us debug this: [ 76.980355][ T2404] Possible unsafe locking scenario: [ 76.980355][ T2404] [ 76.987803][ T2404] CPU0 [ 76.991077][ T2404] ---- [ 76.994345][ T2404] lock(&tree->tree_lock/1); [ 76.999022][ T2404] lock(&tree->tree_lock/1); [ 77.003695][ T2404] [ 77.003695][ T2404] *** DEADLOCK *** [ 77.003695][ T2404] [ 77.011825][ T2404] May be due to missing lock nesting notation [ 77.011825][ T2404] [ 77.020132][ T2404] 5 locks held by kworker/u4:6/2404: [ 77.025405][ T2404] #0: ffff888143e7c938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 [ 77.036027][ T2404] #1: ffffc9000afb7d80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 [ 77.047860][ T2404] #2: ffff8880210f0848 (&hip->extents_lock){+.+.}-{3:3}, at: hfsplus_ext_write_extent+0x82/0x200 [ 77.058473][ T2404] #3: ffff88801c8da0b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfsplus_find_init+0x16e/0x200 [ 77.068658][ T2404] #4: ffff88807f5c9588 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfsplus_file_extend+0x1c1/0x1090 [ 77.080136][ T2404] [ 77.080136][ T2404] stack backtrace: [ 77.086013][ T2404] CPU: 1 PID: 2404 Comm: kworker/u4:6 Not tainted 6.7.0-rc4-syzkaller #0 [ 77.094417][ T2404] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 [ 77.104469][ T2404] Workqueue: writeback wb_workfn (flush-7:0) [ 77.110460][ T2404] Call Trace: [ 77.113733][ T2404] [ 77.116657][ T2404] dump_stack_lvl+0xd9/0x1b0 [ 77.121259][ T2404] __lock_acquire+0x20f8/0x3b20 [ 77.126114][ T2404] ? lockdep_hardirqs_on_prepare+0x420/0x420 [ 77.132096][ T2404] ? hfsplus_find_init+0x95/0x200 [ 77.137119][ T2404] lock_acquire+0x1ae/0x520 [ 77.141626][ T2404] ? hfsplus_find_init+0x16e/0x200 [ 77.146737][ T2404] ? lock_sync+0x190/0x190 [ 77.151157][ T2404] ? preempt_count_sub+0x160/0x160 [ 77.156384][ T2404] __mutex_lock+0x175/0x9d0 [ 77.160909][ T2404] ? hfsplus_find_init+0x16e/0x200 [ 77.166021][ T2404] ? hfsplus_find_init+0x16e/0x200 [ 77.171130][ T2404] ? mutex_trylock+0x130/0x130 [ 77.175897][ T2404] ? rcu_is_watching+0x12/0xb0 [ 77.180677][ T2404] ? hfsplus_find_init+0x16e/0x200 [ 77.185892][ T2404] hfsplus_find_init+0x16e/0x200 [ 77.190842][ T2404] hfsplus_ext_read_extent+0x18f/0x240 [ 77.196295][ T2404] ? __hfsplus_ext_cache_extent+0x9d0/0x9d0 [ 77.202184][ T2404] ? rcu_is_watching+0x12/0xb0 [ 77.206946][ T2404] hfsplus_file_extend+0x695/0x1090 [ 77.212143][ T2404] ? hfsplus_free_fork+0x820/0x820 [ 77.217252][ T2404] ? trace_contention_end+0xd6/0x100 [ 77.222535][ T2404] ? __mutex_lock+0x1a6/0x9d0 [ 77.227212][ T2404] ? hfsplus_find_init+0x16e/0x200 [ 77.232318][ T2404] ? hfsplus_brec_find+0x3e8/0x520 [ 77.237424][ T2404] ? hfsplus_brec_remove+0x4f0/0x4f0 [ 77.242730][ T2404] ? mutex_trylock+0x130/0x130 [ 77.247498][ T2404] hfsplus_bmap_reserve+0x318/0x410 [ 77.252710][ T2404] __hfsplus_ext_write_extent+0x470/0x5e0 [ 77.258427][ T2404] ? hfsplus_find_init+0x16e/0x200 [ 77.263539][ T2404] hfsplus_ext_write_extent+0x1c5/0x200 [ 77.269080][ T2404] ? hfsplus_ext_cmp_key+0x300/0x300 [ 77.274360][ T2404] ? reacquire_held_locks+0x4c0/0x4c0 [ 77.279732][ T2404] ? do_raw_spin_lock+0x12e/0x2b0 [ 77.284765][ T2404] hfsplus_write_inode+0x22/0x4f0 [ 77.289793][ T2404] __writeback_single_inode+0xa91/0xe90 [ 77.295337][ T2404] ? __mark_inode_dirty+0xd60/0xd60 [ 77.300530][ T2404] ? _raw_spin_unlock+0x28/0x40 [ 77.305373][ T2404] ? wbc_attach_and_unlock_inode+0x561/0x910 [ 77.311371][ T2404] writeback_sb_inodes+0x599/0x1080 [ 77.316594][ T2404] ? sync_inode_metadata+0xe0/0xe0 [ 77.321711][ T2404] ? rcu_is_watching+0x12/0xb0 [ 77.326474][ T2404] ? queue_io+0x3ed/0x4e0 [ 77.330803][ T2404] wb_writeback+0x2a5/0xaa0 [ 77.335378][ T2404] ? __writeback_inodes_wb+0x2d0/0x2d0 [ 77.340835][ T2404] ? reacquire_held_locks+0x4c0/0x4c0 [ 77.346208][ T2404] ? mark_held_locks+0x9f/0xe0 [ 77.350974][ T2404] wb_workfn+0x29c/0xfe0 [ 77.355215][ T2404] ? lockdep_hardirqs_on_prepare+0x351/0x420 [ 77.361204][ T2404] ? inode_wait_for_writeback+0x30/0x30 [ 77.366753][ T2404] ? lock_sync+0x190/0x190 [ 77.371174][ T2404] ? lock_sync+0x190/0x190 [ 77.375599][ T2404] ? reacquire_held_locks+0x4c0/0x4c0 [ 77.380976][ T2404] process_one_work+0x886/0x15d0 [ 77.385915][ T2404] ? lock_sync+0x190/0x190 [ 77.390340][ T2404] ? workqueue_congested+0x300/0x300 [ 77.395628][ T2404] ? assign_work+0x1a0/0x250 [ 77.400219][ T2404] worker_thread+0x8b9/0x1290 [ 77.404899][ T2404] ? process_one_work+0x15d0/0x15d0 [ 77.410126][ T2404] kthread+0x2c6/0x3a0 [ 77.414199][ T2404] ? _raw_spin_unlock_irq+0x23/0x50 [ 77.419421][ T2404] ? kthread_complete_and_exit+0x40/0x40 [ 77.425058][ T2404] ret_from_fork+0x45/0x80 [ 77.429479][ T2404] ? kthread_complete_and_exit+0x40/0x40 [ 77.435110][ T2404] ret_from_fork_asm+0x11/0x20 [ 77.439879][ T2404]