assert "bpfilter_lookup(unit) == NULL" failed in bpf.c (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 969775618695 Replace outside as well as empty cells with t..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=14f97961580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=b660ed9df3b3d9a70525

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/615788b97dd9/disk-96977561.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/94f3424cc2ef/bsd-96977561.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/59563ae6f479/kernel-96977561.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b660ed...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "bpfilter_lookup(unit) == NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/net/bpf.c", line 379
Starting stack trace...
panic(ffffffff834bfce1) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff834fba0a,ffffffff83507e9e,17b,ffffffff83511530) at __assert+0x29 sys/kern/subr_prf.c:-1
bpfopen(11700,1,2000,ffff80003c3e2038) at bpfopen+0x2bd bpfilter_lookup sys/net/bpf.c:1832 [inline]
bpfopen(11700,1,2000,ffff80003c3e2038) at bpfopen+0x2bd sys/net/bpf.c:379
spec_open_clone(ffff800033fa6b78) at spec_open_clone+0x277 sys/kern/spec_vnops.c:722
spec_open(ffff800033fa6b78) at spec_open+0x319 sys/kern/spec_vnops.c:148
VOP_OPEN(ffffee806bf77018,1,ffffee80097fd208,ffff80003c3e2038) at VOP_OPEN+0x8b sys/kern/vfs_vops.c:138
vn_open(ffff800033fa6dc8,1,0) at vn_open+0x7a5 sys/kern/vfs_vnops.c:183
doopenat(ffff80003c3e2038,ffffff9c,200000000000,0,0,0,9768782560ec4596) at doopenat+0x35b sys/kern/vfs_syscalls.c:1163
sys_open(ffff80003c3e2038,ffff800033fa7080,ffff800033fa6fd0) at sys_open+0x59 sys/kern/vfs_syscalls.c:1065
syscall(ffff800033fa7080) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff800033fa7080) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x12cc0a2fab0, count: 246
End of stack trace.
syncing disks...


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