./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor2231266194 <...> Warning: Permanently added '10.128.0.32' (ECDSA) to the list of known hosts. execve("./syz-executor2231266194", ["./syz-executor2231266194"], 0x7ffdc5f7f5e0 /* 10 vars */) = 0 brk(NULL) = 0x5555566a6000 brk(0x5555566a6c40) = 0x5555566a6c40 arch_prctl(ARCH_SET_FS, 0x5555566a6300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 readlink("/proc/self/exe", "/root/syz-executor2231266194", 4096) = 28 brk(0x5555566c7c40) = 0x5555566c7c40 brk(0x5555566c8000) = 0x5555566c8000 mprotect(0x7ff6b8f76000, 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 socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC, IPPROTO_IP) = 3 setsockopt(3, SOL_SOCKET, SO_REUSEPORT, [-2147483644], 4) = 0 bind(3, {sa_family=AF_INET6, sin6_port=htons(0), sin6_flowinfo=htonl(0), inet_pton(AF_INET6, "::", &sin6_addr), sin6_scope_id=0}, 28) = 0 exit_group(0) = ? syzkaller login: [ 50.868346][ T3614] [ 50.870825][ T3614] ============================= [ 50.875743][ T3614] WARNING: suspicious RCU usage [ 50.880600][ T3614] 6.0.0-rc1-syzkaller-00066-g3b06a2755758 #0 Not tainted [ 50.887672][ T3614] ----------------------------- [ 50.892553][ T3614] include/net/sock.h:592 suspicious rcu_dereference_check() usage! [ 50.900509][ T3614] [ 50.900509][ T3614] other info that might help us debug this: [ 50.900509][ T3614] [ 50.910795][ T3614] [ 50.910795][ T3614] rcu_scheduler_active = 2, debug_locks = 1 [ 50.918904][ T3614] 4 locks held by syz-executor223/3614: [ 50.924463][ T3614] #0: ffff888076378210 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x280 [ 50.935065][ T3614] #1: ffffc900014e2fc8 (&table->hash[i].lock){+...}-{2:2}, at: udp_lib_unhash+0x1d5/0x730 [ 50.945139][ T3614] #2: ffffffff8d7bc038 (reuseport_lock){+...}-{2:2}, at: reuseport_detach_sock+0x22/0x4a0 [ 50.955195][ T3614] #3: ffff88801d27abb8 (clock-AF_INET6){++..}-{2:2}, at: bpf_sk_reuseport_detach+0x26/0x190 [ 50.965448][ T3614] [ 50.965448][ T3614] stack backtrace: [ 50.971377][ T3614] CPU: 1 PID: 3614 Comm: syz-executor223 Not tainted 6.0.0-rc1-syzkaller-00066-g3b06a2755758 #0 [ 50.981802][ T3614] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 [ 50.991868][ T3614] Call Trace: [ 50.995143][ T3614] [ 50.998072][ T3614] dump_stack_lvl+0xcd/0x134 [ 51.002666][ T3614] bpf_sk_reuseport_detach+0x156/0x190 [ 51.008122][ T3614] reuseport_detach_sock+0x8c/0x4a0 [ 51.013332][ T3614] udp_lib_unhash+0x210/0x730 [ 51.018016][ T3614] ? udpv6_pre_connect+0x180/0x180 [ 51.023143][ T3614] sk_common_release+0xba/0x390 [ 51.027994][ T3614] inet_release+0x12e/0x270 [ 51.032494][ T3614] inet6_release+0x4c/0x70 [ 51.036902][ T3614] __sock_release+0xcd/0x280 [ 51.041483][ T3614] sock_close+0x18/0x20 [ 51.045628][ T3614] __fput+0x277/0x9d0 [ 51.049602][ T3614] ? __sock_release+0x280/0x280 [ 51.054462][ T3614] task_work_run+0xdd/0x1a0 [ 51.058981][ T3614] do_exit+0xad5/0x29b0 [ 51.063145][ T3614] ? mm_update_next_owner+0x7a0/0x7a0 [ 51.068517][ T3614] ? _raw_spin_unlock_irq+0x1f/0x40 [ 51.073736][ T3614] ? _raw_spin_unlock_irq+0x1f/0x40 [ 51.078933][ T3614] do_group_exit+0xd2/0x2f0 [ 51.083446][ T3614] __x64_sys_exit_group+0x3a/0x50 [ 51.088463][ T3614] do_syscall_64+0x35/0xb0 [ 51.092889][ T3614] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 51.098798][ T3614] RIP: 0033:0x7ff6b8f08679 [ 51.103215][ T3614] Code: Unable to access opcode bytes at RIP 0x7ff6b8f0864f. [ 51.110595][ T3614] RSP: 002b:00007ffe5c7dacd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 +++ exited with 0 +++ [ 51.119