uvm_fault(0xffffffff83a25c80, 0xffff800028812004, 0, 1) -> d
kernel: page fault trap, code=0
Stopped at      ufs_readdir+0x26e:      movzwl  0x4(%r14),%ebx
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*181569  28058      0         0x2          0    0  syz-executor
ufs_readdir(ffff80002a7d1630) at ufs_readdir+0x26e sys/ufs/ufs/ufs_vnops.c:1397
VOP_READDIR(fffffd805ec13600,ffff80002a7d16b8,fffffd8007ffd7b8,ffff80002a7d16fc) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453
sys_getdents(ffff80002a766540,ffff80002a7d1840,ffff80002a7d1790) at sys_getdents+0x2dd sys/kern/vfs_syscalls.c:3219
syscall(ffff80002a7d1840) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a7d1840) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x72c8690f4580, count: 10
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(0xffffffff83a25c80, 0xffff800028812004, 0, 1) -> d
ddb> trace
ufs_readdir(ffff80002a7d1630) at ufs_readdir+0x26e sys/ufs/ufs/ufs_vnops.c:1397
VOP_READDIR(fffffd805ec13600,ffff80002a7d16b8,fffffd8007ffd7b8,ffff80002a7d16fc) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453
sys_getdents(ffff80002a766540,ffff80002a7d1840,ffff80002a7d1790) at sys_getdents+0x2dd sys/kern/vfs_syscalls.c:3219
syscall(ffff80002a7d1840) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a7d1840) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x72c8690f4580, count: -5
ddb> show registers
rdi                            0x200
rsi                            0x800
rbp               0xffff80002a7d1620
rbx                            0x200
rdx                                0
rcx               0xfffffd806d9f87e0
rax               0xffff800028812200
r8                0xffffffffffffffff
r9                               0x2
r10               0xf292207f2e0fbc4f
r11               0xd5f5f34d5cf1f5d1
r12                                0
r13               0xffff80002a7d16b8
r14               0xffff800028812000
r15               0xffff800028812008
rip               0xffffffff820abb7e    ufs_readdir+0x26e
cs                               0x8
rflags                       0x10283    __ALIGN_SIZE+0xf283
rsp               0xffff80002a7d1470
ss                              0x10
ufs_readdir+0x26e:      movzwl  0x4(%r14),%ebx
ddb> show proc
PROC (syz-executor) tid=181569 pid=28058 tcnt=1 stat=onproc
    flags process=2<EXEC> proc=0
    runpri=32, usrpri=50, slppri=32, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff80002a766010,0xffff80002a767a10
    process=0xffff80002a79c010 user=0xffff80002a7cc000, vmspace=0xfffffd807ec60b80
    estcpu=36, cpticks=5, pctcpu=0.0, user=0, sys=5, intr=0
ddb>