assert "info->rti_ifa->ifa_ifp != NULL" failed in route.c (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b8b7e987f417 implement "checksum offload" between rport pa..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=138f6304580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=1786a39eee82bc0f7515

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/eaecccb59f68/disk-b8b7e987.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/4e0be55c7f77/bsd-b8b7e987.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/55c001ef326e/kernel-b8b7e987.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1786a3...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "info->rti_ifa->ifa_ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/route.c", line 993
Starting stack trace...
panic(ffffffff83389b4a) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff833c52c9,ffffffff8334af9d,3e1,ffffffff832fc4e0) at __assert+0x29 sys/kern/subr_prf.c:-1
rtrequest(1,ffff8000377e4268,38,ffff8000377e41d0,0) at rtrequest+0xe63 sys/net/route.c:1089
rtm_output(ffff80000153ef00,ffff8000377e4308,ffff8000377e4268,38,0) at
rtm_output+0x93d
route_output(fffffd805bd98e00,ffff800001557208) at route_output+0x9ef sys/net/rtsock.c:858
route_send(ffff800001557208,fffffd805bd98e00,0,0) at route_send+0xd7 sys/net/rtsock.c:322
sosend(ffff800001557208,0,ffff8000377e44b8,0,0,0) at sosend+0x804 sys/kern/uipc_socket.c:-1
sendit(ffff80002a2702b0,7,ffff8000377e45b0,0,ffff8000377e4660) at sendit+0x5a5 sys/kern/uipc_syscalls.c:785
sys_sendto(ffff80002a2702b0,ffff8000377e4710,ffff8000377e4660) at sys_sendto+0x8d sys/kern/uipc_syscalls.c:563
syscall(ffff8000377e4710) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff8000377e4710) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xc5ab3d0a010, count: 246
End of stack trace.


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