login: panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/netinet/if_ether.c", line 776
Starting stack trace...
panic(ffffffff825af16c) at panic+0x16b sys/kern/subr_prf.c:229
__assert(ffffffff82623aaf,ffffffff826235fc,308,ffffffff8257ac08) at __assert+0x25 sys/kern/subr_prf.c:157
arptfree(fffffd80682d6250) at arptfree+0x12e sys/netinet/if_ether.c:776
arptimer(ffffffff82bb5c78) at arptimer+0x88 sys/netinet/if_ether.c:135
timeout_run(ffffffff82bb5c78) at timeout_run+0xcc sys/kern/kern_timeout.c:641
softclock_thread(ffff8000211e82a0) at softclock_thread+0x134 sys/kern/kern_timeout.c:765
end trace frame: 0x0, count: 251
End of stack trace.