panic: mtx_lock() of spin mutex (null) @ /syzkaller/managers/main/kernel/sys/kern/sys_socket.c:309
cpuid = 1
time = 99
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe0025c7c6d0
vpanic() at vpanic+0x1e0/frame 0xfffffe0025c7c730
panic() at panic+0x43/frame 0xfffffe0025c7c790
__mtx_lock_flags() at __mtx_lock_flags+0x1fd/frame 0xfffffe0025c7c7f0
soo_stat() at soo_stat+0x9c/frame 0xfffffe0025c7c830
kern_fstat() at kern_fstat+0xe9/frame 0xfffffe0025c7c880
sys_fstat() at sys_fstat+0x2b/frame 0xfffffe0025c7c980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe0025c7cab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe0025c7cab0
--- syscall (198, FreeBSD ELF64, nosys), rip = 0x41309a, rsp = 0x7fffdffbbf38, rbp = 0x2 ---
KDB: enter: panic
[ thread pid 7747 tid 101160 ]
Stopped at      kdb_enter+0x6a: movq    $0,kdb_why