panic: kernel diagnostic assertion "cifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/net/route.c", line 951
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*397173  67475      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
__assert(ffffffff821e4402,ffffffff821b4fcf,3b7,ffffffff821c51a7) at __assert+0x2b sys/kern/subr_prf.c:154
rtrequest(1,ffff80001490ff88,4,ffff800014910058,0) at rtrequest+0xbf1 sys/net/route.c:951
rt_ifa_add(ffff800000ac2500,840100,ffff800000ac2558,0) at rt_ifa_add+0x290 sys/net/route.c:1133
in_ifinit(ffff800000a6d800,ffff800000ac2500,ffff800014910360,0) at in_ifinit+0x37a in_insert_prefix sys/netinet/in.c:717 [inline]
in_ifinit(ffff800000a6d800,ffff800000ac2500,ffff800014910360,0) at in_ifinit+0x37a sys/netinet/in.c:648
in_ioctl_change_ifaddr(8040691a,ffff800014910350,ffff800000a6d800,1) at in_ioctl_change_ifaddr+0x5de sys/netinet/in.c:452
in_ioctl(8040691a,ffff800014910350,ffff800000a6d800,1) at in_ioctl+0x205 sys/netinet/in.c:234
ifioctl(fffffd803d88dc00,8040691a,ffff800014910350,ffff8000ffff2508) at ifioctl+0xb34 sys/net/if.c:2202
sys_ioctl(ffff8000ffff2508,ffff800014910468,ffff8000149104b0) at sys_ioctl+0x5b9
syscall(ffff800014910530) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff36,0,3,77ecf601010) at Xsyscall+0x128
end of kernel
end trace frame: 0x780e703a070, count: 3
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