panic: kernel diagnostic assertion "rt->rt_ifa->ifa_ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/net/route.c", line 848
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*398703  74635      0        0x10  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
__assert(ffffffff821e514f,ffffffff821b7c3b,350,ffffffff8218b943) at __assert+0x2b sys/kern/subr_prf.c:154
rtrequest(b,ffff8000148fd038,83,ffff8000148fd0d8,0) at rtrequest+0xbd2 sys/net/route.c:951
rt_match(fffffd8039f474e0,0,1,0) at rt_match+0xbe rt_clone sys/net/route.c:266 [inline]
rt_match(fffffd8039f474e0,0,1,0) at rt_match+0xbe sys/net/route.c:242
in_pcbselsrc(ffff8000148fd1b0,fffffd802f1c8b20,fffffd8039f47460) at in_pcbselsrc+0x219 sys/netinet/in_pcb.c:934
in_pcbconnect(fffffd8039f47460,fffffd802f1c8b00) at in_pcbconnect+0x107 sys/netinet/in_pcb.c:492
udp_usrreq(fffffd802caa8078,4,0,fffffd802f1c8b00,0,ffff8000ffff33d8) at udp_usrreq+0x560
sys_connect(ffff8000ffff33d8,ffff8000148fd338,ffff8000148fd380) at sys_connect+0x3df sys/kern/uipc_syscalls.c:388
syscall(ffff8000148fd400) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,fffffffffffffed2,0,3,d6333423010) at Xsyscall+0x128
end of kernel
end trace frame: 0xd6591fe5c50, count: 4
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