uvm_fault(0xffffffff839e1dc0, 0xffff800028b62004, 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
*302798  63870      0         0x2          0    0  syz-executor
ufs_readdir(ffff80002a80f680) at ufs_readdir+0x26e sys/ufs/ufs/ufs_vnops.c:1397
VOP_READDIR(fffff5807ead20e0,ffff80002a80f708,fffff58007ffd6e8,ffff80002a80f74c) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453
sys_getdents(ffff80002a767a00,ffff80002a80f890,ffff80002a80f7e0) at sys_getdents+0x2dd sys/kern/vfs_syscalls.c:3133
syscall(ffff80002a80f890) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a80f890) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7272ab42caa0, 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(0xffffffff839e1dc0, 0xffff800028b62004, 0, 1) -> d
ddb> show kasan
No such command
ddb> trace
ufs_readdir(ffff80002a80f680) at ufs_readdir+0x26e sys/ufs/ufs/ufs_vnops.c:1397
VOP_READDIR(fffff5807ead20e0,ffff80002a80f708,fffff58007ffd6e8,ffff80002a80f74c) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453
sys_getdents(ffff80002a767a00,ffff80002a80f890,ffff80002a80f7e0) at sys_getdents+0x2dd sys/kern/vfs_syscalls.c:3133
syscall(ffff80002a80f890) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a80f890) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7272ab42caa0, count: -5
ddb> show registers
rdi                            0x200
rsi                            0x800
rbp               0xffff80002a80f670
rbx                            0x200
rdx                                0
rcx               0xfffff580671836a0
rax               0xffff800028b62200
r8                0xffffffffffffffff
r9                               0x2
r10               0x5bb0332e8e7ffc90
r11               0x4d89ff356959581c
r12                                0
r13               0xffff80002a80f708
r14               0xffff800028b62000
r15               0xffff800028b62008
rip               0xffffffff81d4133e    ufs_readdir+0x26e
cs                               0x8
rflags                       0x10283    __ALIGN_SIZE+0xf283
rsp               0xffff80002a80f4c0
ss                              0x10
ufs_readdir+0x26e:      movzwl  0x4(%r14),%ebx
ddb>