./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor13351615 <...> Warning: Permanently added '10.128.1.97' (ED25519) to the list of known hosts. execve("./syz-executor13351615", ["./syz-executor13351615"], 0x7ffc059adf80 /* 10 vars */) = 0 brk(NULL) = 0x55557e26d000 brk(0x55557e26dd00) = 0x55557e26dd00 arch_prctl(ARCH_SET_FS, 0x55557e26d380) = 0 set_tid_address(0x55557e26d650) = 5066 set_robust_list(0x55557e26d660, 24) = 0 rseq(0x55557e26dca0, 0x20, 0, 0x53053053) = 0 prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0 readlink("/proc/self/exe", "/root/syz-executor13351615", 4096) = 26 getrandom("\xa3\x1b\x4c\x83\x2b\x76\xea\x4b", 8, GRND_NONBLOCK) = 8 brk(NULL) = 0x55557e26dd00 brk(0x55557e28ed00) = 0x55557e28ed00 brk(0x55557e28f000) = 0x55557e28f000 mprotect(0x7fec5aa55000, 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 clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x55557e26d650) = 5067 ./strace-static-x86_64: Process 5067 attached [pid 5067] set_robust_list(0x55557e26d660, 24) = 0 [pid 5067] prctl(PR_SET_PDEATHSIG, SIGKILL) = 0 [pid 5067] setpgid(0, 0) = 0 [pid 5067] openat(AT_FDCWD, "/proc/self/oom_score_adj", O_WRONLY|O_CLOEXEC) = 3 [pid 5067] write(3, "1000", 4) = 4 [pid 5067] close(3) = 0 [pid 5067] bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_LPM_TRIE, key_size=5, value_size=2, max_entries=4, map_flags=BPF_F_NO_PREALLOC|BPF_F_NUMA_NODE, inner_map_fd=-1, numa_node=0, map_name="", map_ifindex=0, btf_fd=-1, btf_key_type_id=0, btf_value_type_id=0, btf_vmlinux_value_type_id=0, map_extra=0}, 72) = 3 [pid 5067] bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_RAW_TRACEPOINT, insn_cnt=12, insns=0x20000640, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(0, 0, 0), prog_flags=0, prog_name="", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS, prog_btf_fd=-1, func_info_rec_size=0, func_info=NULL, func_info_cnt=0, line_info_rec_size=0, line_info=NULL, line_info_cnt=0, attach_btf_id=0, attach_prog_fd=0, fd_array=NULL}, 144) = 4 [pid 5067] bpf(BPF_RAW_TRACEPOINT_OPEN, {raw_tracepoint={name="timer_start", prog_fd=4}}, 16) = 5 [ 66.197239][ T5061] [ 66.199628][ T5061] ====================================================== [ 66.206730][ T5061] WARNING: possible circular locking dependency detected [ 66.213745][ T5061] 6.8.0-syzkaller-05236-g443574b03387 #0 Not tainted [ 66.220431][ T5061] ------------------------------------------------------ [ 66.227455][ T5061] sshd/5061 is trying to acquire lock: [ 66.233099][ T5061] ffff8880b9529470 (krc.lock){....}-{2:2}, at: kvfree_call_rcu+0x18a/0x790 [ 66.241996][ T5061] [ 66.241996][ T5061] but task is already holding lock: [ 66.249346][ T5061] ffff88802a6179f8 (&trie->lock){....}-{2:2}, at: trie_delete_elem+0x96/0x6a0 [ 66.258301][ T5061] [ 66.258301][ T5061] which lock already depends on the new lock. [ 66.258301][ T5061] [ 66.268692][ T5061] [ 66.268692][ T5061] the existing dependency chain (in reverse order) is: [ 66.277689][ T5061] [ 66.277689][ T5061] -> #2 (&trie->lock){....}-{2:2}: [ 66.284973][ T5061] lock_acquire+0x1e4/0x530 [ 66.289988][ T5061] _raw_spin_lock_irqsave+0xd5/0x120 [ 66.295824][ T5061] trie_delete_elem+0x96/0x6a0 [ 66.301131][ T5061] bpf_prog_2c29ac5cdc6b1842+0x42/0x46 [ 66.307161][ T5061] bpf_trace_run2+0x204/0x420 [ 66.312384][ T5061] enqueue_timer+0x396/0x550 [ 66.317774][ T5061] __mod_timer+0x953/0xeb0 [ 66.322806][ T5061] sk_reset_timer+0x23/0xc0 [ 66.327840][ T5061] tcp_event_new_data_sent+0x203/0x360 [ 66.333840][ T5061] tcp_write_xmit+0x1468/0x6100 [ 66.339205][ T5061] __tcp_push_pending_frames+0x9b/0x360 [ 66.345291][ T5061] tcp_sendmsg_locked+0x42cc/0x4d00 [ 66.351027][ T5061] tcp_sendmsg+0x30/0x50 [ 66.355774][ T5061] __sock_sendmsg+0x1a6/0x270 [ 66.360981][ T5061] sock_write_iter+0x2dd/0x400 [ 66.366260][ T5061] vfs_write+0xa84/0xcb0 [ 66.371016][ T5061] ksys_write+0x1a0/0x2c0 [ 66.375855][ T5061] do_syscall_64+0xfb/0x240 [ 66.380899][ T5061] entry_SYSCALL_64_after_hwframe+0x6d/0x75 [ 66.387480][ T5061] [ 66.387480][ T5061] -> #1 (&base->lock){-.-.}-{2:2}: [ 66.395027][ T5061] lock_acquire+0x1e4/0x530 [ 66.400126][ T5061] _raw_spin_lock_irqsave+0xd5/0x120 [ 66.405919][ T5061] lock_timer_base+0x112/0x240 [ 66.411198][ T5061] __mod_timer+0x1ca/0xeb0 [ 66.416123][ T5061] queue_delayed_work_on+0x15a/0x260 [ 66.421915][ T5061] kvfree_call_rcu+0x47f/0x790 [ 66.427359][ T5061] rtnl_register_internal+0x482/0x590 [ 66.433241][ T5061] rtnl_register+0x36/0x80 [ 66.438167][ T5061] ip_rt_init+0x2f5/0x3a0 [ 66.443354][ T5061] ip_init+0xe/0x20 [ 66.447766][ T5061] inet_init+0x3d8/0x580 [ 66.452515][ T5061] do_one_initcall+0x238/0x830 [ 66.457804][ T5061] do_initcall_level+0x157/0x210 [ 66.463269][ T5061] do_initcalls+0x3f/0x80 [ 66.468211][ T5061] kernel_init_freeable+0x435/0x5d0 [ 66.474022][ T5061] kernel_init+0x1d/0x2a0 [ 66.478896][ T5061] ret_from_fork+0x4b/0x80 [ 66.483920][ T5061] ret_from_fork_asm+0x1a/0x30 [ 66.489294][ T5061] [ 66.489294][ T5061] -> #0 (krc.lock){....}-{2:2}: [ 66.496758][ T5061] validate_chain+0x18cb/0x58e0 [ 66.502225][ T5061] __lock_acquire+0x1346/0x1fd0 [ 66.507583][ T5061] lock_acquire+0x1e4/0x530 [ 66.512704][ T5061] _raw_spin_lock+0x2e/0x40 [ 66.517897][ T5061] kvfree_call_rcu+0x18a/0x790 [ 66.523272][ T5061] trie_delete_elem+0x52c/0x6a0 [ 66.528638][ T5061] bpf_prog_2c29ac5cdc6b1842+0x42/0x46 [ 66.534782][ T5061] bpf_trace_run2+0x204/0x420 [ 66.540067][ T5061] enqueue_timer+0x396/0x550 [ 66.545165][ T5061] __mod_timer+0x953/0xeb0 [ 66.550161][ T5061] sk_reset_timer+0x23/0xc0 [ 66.555294][ T5061] tcp_schedule_loss_probe+0x419/0x560 [ 66.561279][ T5061] tcp_write_xmit+0x3682/0x6100 [ 66.566759][ T5061] __tcp_push_pending_frames+0x9b/0x360 [ 66.572851][ T5061] tcp_sendmsg_locked+0x42cc/0x4d00 [ 66.578590][ T5061] tcp_sendmsg+0x30/0x50 [ 66.583344][ T5061] __sock_sendmsg+0x1a6/0x270 [ 66.588710][ T5061] sock_write_iter+0x2dd/0x400 [ 66.594010][ T5061] vfs_write+0xa84/0xcb0 [ 66.598869][ T5061] ksys_write+0x1a0/0x2c0 [ 66.603887][ T5061] do_syscall_64+0xfb/0x240 [ 66.609020][ T5061] entry_SYSCALL_64_after_hwframe+0x6d/0x75 [ 66.615710][ T5061] [ 66.615710][ T5061] other info that might help us debug this: [ 66.615710][ T5061] [ 66.626108][ T5061] Chain exists of: [ 66.626108][ T5061] krc.lock --> &base->lock --> &trie->lock [ 66.626108][ T5061] [ 66.638185][ T5061] Possible unsafe locking scenario: [ 66.638185][ T5061] [ 66.645795][ T5061] CPU0 CPU1 [ 66.651406][ T5061] ---- ---- [ 66.657112][ T5061] lock(&trie->lock); [ 66.661285][ T5061] lock(&base->lock); [ 66.668172][ T5061] lock(&trie->lock); [ 66.674766][ T5061] lock(krc.lock); [ 66.678750][ T5061] [ 66.678750][ T5061] *** DEADLOCK *** [ 66.678750][ T5061] [ 66.689486][ T5061] 4 locks held by sshd/5061: [ 66.694058][ T5061] #0: ffff88802cdda718 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x22/0x50 [ 66.703191][ T5061] #1: ffff8880b952a758 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x112/0x240 [ 66.712504][ T5061] #2: ffffffff8e131920 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x114/0x420 [ 66.721979][ T5061] #3: ffff88802a6179f8 (&trie->lock){....}-{2:2}, at: trie_delete_elem+0x96/0x6a0 [ 66.731287][ T5061] [ 66.731287][ T5061] stack backtrace: [ 66.737368][ T5061] CPU: 1 PID: 5061 Comm: sshd Not tainted 6.8.0-syzkaller-05236-g443574b03387 #0 [ 66.746784][ T5061] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 [ 66.757012][ T5061] Call Trace: [ 66.760297][ T5061] [ 66.763310][ T5061] dump_stack_lvl+0x1e7/0x2e0 [ 66.768951][ T5061] ? __pfx_dump_stack_lvl+0x10/0x10 [ 66.774149][ T5061] ? print_circular_bug+0x130/0x1a0 [ 66.779345][ T5061] check_noncircular+0x36a/0x4a0 [ 66.784289][ T5061] ? __pfx_check_noncircular+0x10/0x10 [ 66.789917][ T5061] ? lockdep_lock+0x123/0x2b0 [ 66.794595][ T5061] ? mark_lock+0x9a/0x350 [ 66.799029][ T5061] ? _find_first_zero_bit+0xd4/0x100 [ 66.804578][ T5061] validate_chain+0x18cb/0x58e0 [ 66.810300][ T5061] ? __pfx_validate_chain+0x10/0x10 [ 66.815923][ T5061] ? stack_depot_save_flags+0x37d/0x860 [ 66.821540][ T5061] ? do_raw_spin_lock+0x14f/0x370 [ 66.826815][ T5061] ? __pfx_lock_release+0x10/0x10 [ 66.831932][ T5061] ? do_raw_spin_unlock+0x13c/0x8b0 [ 66.837139][ T5061] ? _raw_spin_unlock_irqrestore+0xdd/0x140 [ 66.843198][ T5061] ? __pfx__raw_spin_unlock_irqrestore+0x10/0x10 [ 66.849625][ T5061] ? stack_trace_save+0x118/0x1d0 [ 66.854646][ T5061] ? mark_lock+0x9a/0x350 [ 66.858974][ T5061] __lock_acquire+0x1346/0x1fd0 [ 66.863829][ T5061] lock_acquire+0x1e4/0x530 [ 66.868321][ T5061] ? kvfree_call_rcu+0x18a/0x790 [ 66.873250][ T5061] ? __pfx_lock_acquire+0x10/0x10 [ 66.878266][ T5061] ? __phys_addr+0xba/0x170 [ 66.882763][ T5061] _raw_spin_lock+0x2e/0x40 [ 66.887603][ T5061] ? kvfree_call_rcu+0x18a/0x790 [ 66.892622][ T5061] kvfree_call_rcu+0x18a/0x790 [ 66.897532][ T5061] ? _raw_spin_lock_irqsave+0xe1/0x120 [ 66.902984][ T5061] ? __pfx_kvfree_call_rcu+0x10/0x10 [ 66.908345][ T5061] ? longest_prefix_match+0x4bf/0x670 [ 66.913713][ T5061] trie_delete_elem+0x52c/0x6a0 [ 66.918720][ T5061] bpf_prog_2c29ac5cdc6b1842+0x42/0x46 [ 66.924431][ T5061] bpf_trace_run2+0x204/0x420 [ 66.929098][ T5061] ? bpf_trace_run2+0x114/0x420 [ 66.933938][ T5061] ? __pfx_bpf_trace_run2+0x10/0x10 [ 66.939294][ T5061] ? __pfx_debug_object_activate+0x10/0x10 [ 66.945082][ T5061] ? _raw_spin_unlock_irqrestore+0xdd/0x140 [ 66.951049][ T5061] ? rcu_is_watching+0x15/0xb0 [ 66.955802][ T5061] enqueue_timer+0x396/0x550 [ 66.960509][ T5061] __mod_timer+0x953/0xeb0 [ 66.964920][ T5061] ? __pfx___mod_timer+0x10/0x10 [ 66.970233][ T5061] sk_reset_timer+0x23/0xc0 [ 66.974747][ T5061] tcp_schedule_loss_probe+0x419/0x560 [ 66.980220][ T5061] tcp_write_xmit+0x3682/0x6100 [ 66.985179][ T5061] __tcp_push_pending_frames+0x9b/0x360 [ 66.990724][ T5061] tcp_sendmsg_locked+0x42cc/0x4d00 [ 66.995945][ T5061] ? __pfx_tcp_sendmsg_locked+0x10/0x10 [ 67.001691][ T5061] ? __local_bh_enable_ip+0x168/0x200 [ 67.007070][ T5061] ? do_raw_spin_unlock+0x13c/0x8b0 [ 67.012302][ T5061] tcp_sendmsg+0x30/0x50 [ 67.016554][ T5061] __sock_sendmsg+0x1a6/0x270 [ 67.021250][ T5061] sock_write_iter+0x2dd/0x400 [ 67.026116][ T5061] ? __pfx_sock_write_iter+0x10/0x10 [ 67.031429][ T5061] ? bpf_lsm_file_permission+0x9/0x10 [ 67.036814][ T5061] ? security_file_permission+0x7f/0xa0 [ 67.042358][ T5061] vfs_write+0xa84/0xcb0 [ 67.046617][ T5061] ? __pfx_vfs_write+0x10/0x10 [ 67.051373][ T5061] ? __set_current_blocked+0x310/0x380 [ 67.057191][ T5061] ? __might_fault+0xc6/0x120 [ 67.061861][ T5061] ? __fdget_pos+0x1a2/0x320 [ 67.066461][ T5061] ksys_write+0x1a0/0x2c0 [ 67.070784][ T5061] ? __pfx_ksys_write+0x10/0x10 [ 67.075625][ T5061] ? do_syscall_64+0x10a/0x240 [ 67.080497][ T5061] ? do_syscall_64+0xb6/0x240 [ 67.085219][ T5061] do_syscall_64+0xfb/0x240 [ 67.089715][ T5061] entry_SYSCALL_64_after_hwframe+0x6d/0x75 [ 67.095692][ T5061] RIP: 0033:0x7f3d5b516bf2 [ 67.100095][ T5061] Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83 [ 67.120066][ T5061] RSP: 002b:00007ffe602e06a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 67.128832][ T5061] RAX: ffffffffffffffda RBX: 000000000000002c RCX: 00007f3d5b516bf2 [ 67.136793][ T5061] RDX: 000000000000002c RSI: 0000559d1d0d1960 RDI: 0000000000000004 [ 67.144768][ T5061] RBP: 0000559d1d0dade0 R08: 0000000000000000 R09: 0000000000000000 [ 67.153171][ T5061] R10: 0000000000000000 R11: 0000000000000246 R12: 0000559cf518daa4 [ 67.161218][ T5061] R13: 0000000000000042 R14: 0000559cf518e3e8 R15: 00007ffe602e0718 [ 67.169229][ T5061]