panic: attempt to execute user address 0x0 in supervisor mode
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 56611  74530      0           0  0x4000000    0  syz-executor.1
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
pageflttrap() at pageflttrap+0x3eb
kerntrap(ffff800015938570) at kerntrap+0xdb sys/arch/amd64/amd64/trap.c:287
alltraps_kern_meltdown(6,ffff800015533000,fffffd802eee9af8,10,ffff80000005b6b0,ffff8000159387d8) at alltraps_kern_meltdown+0x7b
0(b,ffff800015938738,83,ffff8000159387d8,0,b) at 0
rt_match(fffffd803789c2b0,0,1,0) at rt_match+0xbe rt_clone sys/net/route.c:266 [inline]
rt_match(fffffd803789c2b0,0,1,0) at rt_match+0xbe sys/net/route.c:242
in_pcbselsrc(ffff8000159388b0,fffffd8034b8cf20,fffffd803789c230) at in_pcbselsrc+0x219 sys/netinet/in_pcb.c:934
in_pcbconnect(fffffd803789c230,fffffd8034b8cf00) at in_pcbconnect+0x107 sys/netinet/in_pcb.c:492
udp_usrreq(fffffd8037a22620,4,0,fffffd8034b8cf00,0,ffff8000ffff2290) at udp_usrreq+0x560
sys_connect(ffff8000ffff2290,ffff800015938a38,ffff800015938a80) at sys_connect+0x3df sys/kern/uipc_syscalls.c:388
syscall(ffff800015938b00) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,fffffffffffffed2,0,3,f89e366c010) at Xsyscall+0x128
end of kernel
end trace frame: 0xf8cd6b83750, count: 2
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