uvm_fault(0xffffffff83a0d4d0, 0xffff800020f72004, 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 *356320 3663 0 0x2 0 0 syz-executor ufs_readdir(ffff80002a8a3200) at ufs_readdir+0x26e sys/ufs/ufs/ufs_vnops.c:1397 VOP_READDIR(fffff2006d192dc8,ffff80002a8a3288,fffff20007ffd548,ffff80002a8a32cc) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453 sys_getdents(ffff80002a7362a0,ffff80002a8a3410,ffff80002a8a3360) at sys_getdents+0x2dd sys/kern/vfs_syscalls.c:3133 syscall(ffff80002a8a3410) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a8a3410) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7bccc6ee3ed0, 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(0xffffffff83a0d4d0, 0xffff800020f72004, 0, 1) -> d ddb> show kasan No such command ddb> trace ufs_readdir(ffff80002a8a3200) at ufs_readdir+0x26e sys/ufs/ufs/ufs_vnops.c:1397 VOP_READDIR(fffff2006d192dc8,ffff80002a8a3288,fffff20007ffd548,ffff80002a8a32cc) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453 sys_getdents(ffff80002a7362a0,ffff80002a8a3410,ffff80002a8a3360) at sys_getdents+0x2dd sys/kern/vfs_syscalls.c:3133 syscall(ffff80002a8a3410) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a8a3410) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7bccc6ee3ed0, count: -5 ddb> show registers rdi 0x200 rsi 0x800 rbp 0xffff80002a8a31f0 rbx 0x200 rdx 0 rcx 0xfffff200691d6370 rax 0xffff800020f72200 r8 0xffffffffffffffff r9 0x3 r10 0xfbc4937f57890179 r11 0x90b19c7fa69ed393 r12 0 r13 0xffff80002a8a3288 r14 0xffff800020f72000 r15 0xffff800020f72008 rip 0xffffffff82e89eae ufs_readdir+0x26e cs 0x8 rflags 0x10283 __ALIGN_SIZE+0xf283 rsp 0xffff80002a8a3040 ss 0x10 ufs_readdir+0x26e: movzwl 0x4(%r14),%ebx ddb> show proc PROC (syz-executor) tid=356320 pid=3663 tcnt=1 stat=onproc flags process=2 proc=0 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a736f98,0xffff80003c8fb4f0 process=0xffff80002a79f610 user=0xffff80002a89e000, vmspace=0xfffff2006fa43458 estcpu=36, cpticks=10, pctcpu=0.1, user=0, sys=10, intr=0 ddb> ps PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND 96541 129446 86706 0 2 0 0xc80 syz-executor 96541 210060 86706 0 3 0 0x4000080 lockf syz-executor 96541 226724 86706 0 3 0 0x4000080 fsleep syz-executor 96541 372098 86706 0 3 0 0x4000080 fsleep syz-executor 86935 100308 74337 0 3 0 0x80 nanoslp syz-executor 86935 520474 74337 0 3 0 0x4000088 kqpoll syz-executor 86935 285204 74337 0 3 0 0x4000080 fsleep syz-executor 72970 112376 0 0 3 0x14000 0x280 nfsidl nfsio 81050 147185 0 0 3 0x14000 0x280 nfsidl nfsio 37712 476461 0 0 3 0x14000 0x280 nfsidl nfsio 43939 229254 0 0 3 0x14000 0x280 nfsidl nfsio 62053 42514 0 0 3 0x14000 0x280 nfsidl nfsio 13066 170939 0 0 3 0x14000 0x280 nfsidl nfsio 84176 314808 0 0 3 0x14000 0x280 nfsidl nfsio 34668 76020 0 0 3 0x14000 0x280 nfsidl nfsio 3910 156524 0 0 3 0x14000 0x280 nfsidl nfsio 79408 475803 0 0 3 0x14000 0x280 nfsidl nfsio 78925 500122 0 0 3 0x14000 0x280 nfsidl nfsio 54906 163224 0 0 3 0x14000 0x280 nfsidl nfsio 70584 1176 0 0 3 0x14000 0x280 nfsidl nfsio 80082 61123 0 0 3 0x14000 0x280 nfsidl nfsio 87543 508468 0 0 3 0x14000 0x280 nfsidl nfsio 99122 479304 0 0 3 0x14000 0x280 nfsidl nfsio 29622 157341 0 0 3 0x14000 0x280 nfsidl nfsio 77793 208209 0 0 3 0x14000 0x280 nfsidl nfsio 9147 518574 0 0 3 0x14000 0x280 nfsidl nfsio 85484 479187 0 0 3 0x14000 0x280 nfsidl nfsio 96586 270093 1 0 3 0x100003 0x80 ttyin getty 42105 420735 0 0 3 0x14000 0x200 acct acct * 3663 356320 9386 0 7 0x2 0 syz-executor 59319 39920 9386 0 3 0x2 0x80 nanoslp syz-executor 74337 167694 9386 0 3 0x2 0x80 nanoslp syz-executor 86706 94556 9386 0 3 0x2 0x80 nanoslp syz-executor 9386 401594 1 0 3 0x2 0x80 wait syz-executor 74990 296046 1 73 3 0x1100010 0x80 kqread syslogd 35080 132496 0 0 3 0x14000 0x200 bored smr 28181 184735 0 0 2 0x14000 0x200 zerothread 76270 336965 0 0 3 0x14000 0x200 aiodoned aiodoned 70821 149023 0 0 3 0x14000 0x200 syncer update 65559 347105 0 0 3 0x14000 0x200 cleaner cleaner 35211 332699 0 0 3 0x14000 0x200 reaper reaper 7025 248181 0 0 3 0x14000 0x200 pgdaemon pagedaemon 28370 199718 0 0 3 0x14000 0x200 bored viomb 97131 256644 0 0 3 0x14000 0x40000200 acpi0 acpi0 8182 416983 0 0 3 0x14000 0x200 bored softnet0 45949 245081 0 0 3 0x14000 0x200 bored systqmp 92252 43338 0 0 3 0x14000 0x200 bored systq 81689 73529 0 0 3 0x14000 0x40000200 tmoslp softclock 83863 78447 0 0 3 0x14000 0x40000200 idle0 1 272572 0 0 3 0x2 0x80 wait init 0 0 -1 0 3 0x10000 0x200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11031 12101K 12573K 166960K 13088 0 pcb 17 14K 16K 166960K 92 0 rtable 224 7K 10K 166960K 413 0 pf 34 13K 19K 166960K 92 0 ifaddr 40 6K 7K 166960K 60 0 ifgroup 54 2K 2K 166960K 84 0 sysctl 4 1K 9K 166960K 9 0 counters 34 17K 18K 166960K 49 0 ioctlops 0 0K 4K 166960K 195 0 iov 0 0K 20K 166960K 19 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1393 88K 88K 166960K 1832 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 8 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 95 0 dirhash 12 2K 2K 166960K 21 0 ACPI 1734 201K 291K 166960K 11964 0 file desc 13 45K 97K 166960K 531 0 sigio 0 0K 0K 166960K 4 0 proc 20 25K 124K 166960K 564 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 47 0 in_multi 88 6K 7K 166960K 112 0 ether_multi 1 0K 0K 166960K 4 0 mrt 0 0K 0K 166960K 20 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0