panic: kernel diagnostic assertion "bpfilter_lookup(unit) == NULL" failed: file "/syzkaller/managers/main/kernel/sys/net/bpf.c", line 379
Stopped at      db_enter+0x25:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*514965  29245      0           0  0x4000000    0  syz-executor
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8341b8bd) at panic+0x1cf sys/kern/subr_prf.c:198
__assert(ffffffff8345594a,ffffffff83439954,17b,ffffffff83468af7) at __assert+0x29 sys/kern/subr_prf.c:-1
bpfopen(11700,8001,2000,ffff80002a88ed28) at bpfopen+0x27d
spec_open_clone(ffff80003c8fd598) at spec_open_clone+0x277 sys/kern/spec_vnops.c:722
spec_open(ffff80003c8fd598) at spec_open+0x316 sys/kern/spec_vnops.c:148
VOP_OPEN(fffffd8068a8b8b0,8001,fffffd8007ffd5b0,ffff80002a88ed28) at VOP_OPEN+0x82 sys/kern/vfs_vops.c:138
vn_open(ffff80003c8fd7f0,8001,0) at vn_open+0x7a5 sys/kern/vfs_vnops.c:183
doopenat(ffff80002a88ed28,ffffff9c,200000000000,8000,0,0,460d35f02fe6824e) at doopenat+0x352 sys/kern/vfs_syscalls.c:1155
sys_open(ffff80002a88ed28,ffff80003c8fda90,ffff80003c8fd9e0) at sys_open+0x59 sys/kern/vfs_syscalls.c:1063
syscall(ffff80003c8fda90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c8fda90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcabaf3affe0, count: 3
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports.  Insufficient info makes it difficult to find and fix bugs.
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
*cpu0: kernel diagnostic assertion "bpfilter_lookup(unit) == NULL" failed: file "/syzkaller/managers/main/kernel/sys/net/bpf.c", line 379
ddb> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8341b8bd) at panic+0x1cf sys/kern/subr_prf.c:198
__assert(ffffffff8345594a,ffffffff83439954,17b,ffffffff83468af7) at __assert+0x29 sys/kern/subr_prf.c:-1
bpfopen(11700,8001,2000,ffff80002a88ed28) at bpfopen+0x27d
spec_open_clone(ffff80003c8fd598) at spec_open_clone+0x277 sys/kern/spec_vnops.c:722
spec_open(ffff80003c8fd598) at spec_open+0x316 sys/kern/spec_vnops.c:148
VOP_OPEN(fffffd8068a8b8b0,8001,fffffd8007ffd5b0,ffff80002a88ed28) at VOP_OPEN+0x82 sys/kern/vfs_vops.c:138
vn_open(ffff80003c8fd7f0,8001,0) at vn_open+0x7a5 sys/kern/vfs_vnops.c:183
doopenat(ffff80002a88ed28,ffffff9c,200000000000,8000,0,0,460d35f02fe6824e) at doopenat+0x352 sys/kern/vfs_syscalls.c:1155
sys_open(ffff80002a88ed28,ffff80003c8fda90,ffff80003c8fd9e0) at sys_open+0x59 sys/kern/vfs_syscalls.c:1063
syscall(ffff80003c8fda90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c8fda90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcabaf3affe0, count: -12
ddb> show registers
rdi                                0
rsi                              0x1
rbp               0xffff80003c8fd380
rbx                                0
rdx               0xffff8000015de180
rcx                                0
rax               0xffff80002a88ed28
r8                 0x101010101010101
r9                0x8080808080808080
r10               0xac1c925c6fde5d75
r11               0x3d920c0ed26d9ae6
r12                                0
r13                              0x2
r14                                0
r15                              0x1
rip               0xffffffff82b6da75    db_enter+0x25
cs                               0x8
rflags                         0x246
rsp               0xffff80003c8fd370
ss                              0x10
db_enter+0x25:  addq    $0x8,%rsp
ddb> show proc
PROC (syz-executor) tid=514965 pid=29245 tcnt=3 stat=onproc
    flags process=0 proc=4000000<THREAD>
    runpri=86, usrpri=80, slppri=17, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff80002a7662a8,0xffff80002a88f268
    process=0xffff8000ffff68a0 user=0xffff80003c8f8000, vmspace=0xfffffd806cb0c2f0
    estcpu=30, cpticks=2, pctcpu=0.1, user=0, sys=2, intr=0
ddb>