login: uvm_fault(0xffffffff839b9a10, 0xffff800026062004, 0, 1) -> d
kernel: page fault trap, code=0
Stopped at      ufs_lookup+0x613:       movzwl  0x4(%r15,%r14,1),%ebx
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 25555  82237  60929        0x10  0x4000000    0  syz-executor
ufs_lookup() at ufs_lookup+0x613 sys/ufs/ufs/ufs_lookup.c:279
VOP_LOOKUP(fffffd806f1250d8,ffff80002a799170,ffff80002a7991a0) at VOP_LOOKUP+0x6e sys/kern/vfs_vops.c:85
vfs_lookup(ffff80002a799140) at vfs_lookup+0x961 sys/kern/vfs_lookup.c:567
namei(ffff80002a799140) at namei+0x7ca sys/kern/vfs_lookup.c:250
vn_open(ffff80002a799140,1,0) at vn_open+0x178 sys/kern/vfs_vnops.c:146
doopenat(ffff80002a776a70,ffffff9c,200000000080,0,0,0,9d7f20c4d5770c61) at doopenat+0x352 sys/kern/vfs_syscalls.c:1155
sys_open(ffff80002a776a70,ffff80002a7993e0,ffff80002a799330) at sys_open+0x59 sys/kern/vfs_syscalls.c:1063
syscall(ffff80002a7993e0) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a7993e0) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xac6c7c1ee00, count: 6
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: uvm_fault(0xffffffff839b9a10, 0xffff800026062004, 0, 1) -> d
ddb> trace
ufs_lookup() at ufs_lookup+0x613 sys/ufs/ufs/ufs_lookup.c:279
VOP_LOOKUP(fffffd806f1250d8,ffff80002a799170,ffff80002a7991a0) at VOP_LOOKUP+0x6e sys/kern/vfs_vops.c:85
vfs_lookup(ffff80002a799140) at vfs_lookup+0x961 sys/kern/vfs_lookup.c:567
namei(ffff80002a799140) at namei+0x7ca sys/kern/vfs_lookup.c:250
vn_open(ffff80002a799140,1,0) at vn_open+0x178 sys/kern/vfs_vnops.c:146
doopenat(ffff80002a776a70,ffffff9c,200000000080,0,0,0,9d7f20c4d5770c61) at doopenat+0x352 sys/kern/vfs_syscalls.c:1155
sys_open(ffff80002a776a70,ffff80002a7993e0,ffff80002a799330) at sys_open+0x59 sys/kern/vfs_syscalls.c:1063
syscall(ffff80002a7993e0) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a7993e0) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xac6c7c1ee00, count: -9
ddb> show registers
rdi                                0
rsi                              0x2
rbp               0xffff80002a798da0
rbx                                0
rdx               0xffff8000015d3200
rcx                       0xffffffff
rax               0xffff80002a776a70
r8                0xffffffffffffffff
r9                0xfffffd8007ffd1a0
r10               0xa093bbf7cf5f0a9b
r11               0x440f4a495c0c8b15
r12               0xfffffd805ec04120
r13                                0
r14                                0
r15               0xffff800026062000
rip               0xffffffff81502083    ufs_lookup+0x613
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff80002a798cb0
ss                              0x10
ufs_lookup+0x613:       movzwl  0x4(%r15,%r14,1),%ebx
ddb> show proc
PROC (syz-executor) tid=25555 pid=82237 tcnt=2 stat=onproc
    flags process=10<SUGID> proc=4000000<THREAD>
    runpri=32, usrpri=86, slppri=32, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff80002f0c0d10,0xffff80003c90b788
    process=0xffff8000ffff9218 user=0xffff80002a794000, vmspace=0xfffffd806cb27010
    estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb>