./strace-static-x86_64 -e \!wait4,clock_nanosleep,nanosleep -s 100 -x -f ./syz-executor3149107368 <...> Warning: Permanently added '10.128.0.159' (ECDSA) to the list of known hosts. execve("./syz-executor3149107368", ["./syz-executor3149107368"], 0x7ffc88a18230 /* 10 vars */) = 0 brk(NULL) = 0x555557093000 brk(0x555557093c40) = 0x555557093c40 arch_prctl(ARCH_SET_FS, 0x555557093300) = 0 uname({sysname="Linux", nodename="syzkaller", ...}) = 0 readlink("/proc/self/exe", "/root/syz-executor3149107368", 4096) = 28 brk(0x5555570b4c40) = 0x5555570b4c40 brk(0x5555570b5000) = 0x5555570b5000 mprotect(0x7fc269d81000, 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(20000), sin6_flowinfo=htonl(0), inet_pton(AF_INET6, "::ffff:255.255.255.255", &sin6_addr), sin6_scope_id=0}, 28) = 0 exit_group(0) = ? syzkaller login: [ 49.334406][ T3613] [ 49.336852][ T3613] ============================= [ 49.341730][ T3613] WARNING: suspicious RCU usage [ 49.346563][ T3613] 5.19.0-syzkaller-11980-ge34cfee65ec8 #0 Not tainted [ 49.353331][ T3613] ----------------------------- [ 49.358202][ T3613] include/net/sock.h:592 suspicious rcu_dereference_check() usage! [ 49.366100][ T3613] [ 49.366100][ T3613] other info that might help us debug this: [ 49.366100][ T3613] [ 49.376367][ T3613] [ 49.376367][ T3613] rcu_scheduler_active = 2, debug_locks = 1 [ 49.384462][ T3613] 4 locks held by syz-executor314/3613: [ 49.390073][ T3613] #0: ffff888075381a10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release+0x86/0x280 [ 49.400702][ T3613] #1: ffffc900014cd498 (&table->hash[i].lock){+...}-{2:2}, at: udp_lib_unhash+0x1d5/0x730 [ 49.410784][ T3613] #2: ffffffff8d7bb7b8 (reuseport_lock){+...}-{2:2}, at: reuseport_detach_sock+0x22/0x4a0 [ 49.420863][ T3613] #3: ffff88802665b3b8 (clock-AF_INET6){++..}-{2:2}, at: bpf_sk_reuseport_detach+0x26/0x190 [ 49.431109][ T3613] [ 49.431109][ T3613] stack backtrace: [ 49.436997][ T3613] CPU: 0 PID: 3613 Comm: syz-executor314 Not tainted 5.19.0-syzkaller-11980-ge34cfee65ec8 #0 [ 49.447148][ T3613] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 [ 49.457193][ T3613] Call Trace: [ 49.460473][ T3613] [ 49.463397][ T3613] dump_stack_lvl+0xcd/0x134 [ 49.467993][ T3613] bpf_sk_reuseport_detach+0x156/0x190 [ 49.473464][ T3613] reuseport_detach_sock+0x8c/0x4a0 [ 49.478657][ T3613] udp_lib_unhash+0x210/0x730 [ 49.483340][ T3613] ? udpv6_pre_connect+0x180/0x180 [ 49.488446][ T3613] sk_common_release+0xba/0x390 [ 49.493294][ T3613] inet_release+0x12e/0x270 [ 49.497801][ T3613] inet6_release+0x4c/0x70 [ 49.502213][ T3613] __sock_release+0xcd/0x280 [ 49.506797][ T3613] sock_close+0x18/0x20 [ 49.510944][ T3613] __fput+0x277/0x9d0 [ 49.514920][ T3613] ? __sock_release+0x280/0x280 [ 49.519765][ T3613] task_work_run+0xdd/0x1a0 [ 49.524279][ T3613] do_exit+0xad5/0x29b0 [ 49.528525][ T3613] ? mm_update_next_owner+0x7a0/0x7a0 [ 49.533938][ T3613] ? _raw_spin_unlock_irq+0x1f/0x40 [ 49.539161][ T3613] ? _raw_spin_unlock_irq+0x1f/0x40 [ 49.544370][ T3613] do_group_exit+0xd2/0x2f0 [ 49.548880][ T3613] __x64_sys_exit_group+0x3a/0x50 [ 49.553908][ T3613] do_syscall_64+0x35/0xb0 [ 49.558329][ T3613] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 49.564229][ T3613] RIP: 0033:0x7fc269d136a9 [ 49.568645][ T3613] Code: Unable to access opcode bytes at RIP 0x7fc269d1367f. [ 49.576003][ T3613] RSP: 002b:00007ffce3679728 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 +++ exited with 0 +++ [ 49.584416