uvm_fault(0xffffffff82c1dac0, 0xffff80002098f004, 0, 1) -> d
kernel: page fault trap, code=0
Stopped at      ufs_lookup+0x4ce:       movzwl  0x4(%r15,%r13,1),%ebx
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*245315  24060      0           0          0    0  syz-executor.4
ufs_lookup() at ufs_lookup+0x4ce sys/ufs/ufs/ufs_lookup.c:281
VOP_LOOKUP(fffffd806c085d80,ffff800027fd41e8,ffff800027fd4218) at VOP_LOOKUP+0x58 sys/kern/vfs_vops.c:85
vfs_lookup(ffff800027fd41b8) at vfs_lookup+0x6cc sys/kern/vfs_lookup.c:566
namei(ffff800027fd41b8) at namei+0x55a sys/kern/vfs_lookup.c:250
sys_chdir(ffff80002658a038,ffff800027fd42c0,ffff800027fd4310) at sys_chdir+0x72 change_dir sys/kern/vfs_syscalls.c:843 [inline]
sys_chdir(ffff80002658a038,ffff800027fd42c0,ffff800027fd4310) at sys_chdir+0x72 sys/kern/vfs_syscalls.c:789
syscall(ffff800027fd4390) at syscall+0x4e6 sys/arch/amd64/amd64/trap.c:626
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff3010, count: 8
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