panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *306023 53937 0 0x2 0 0 syz-executor.1 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 fifo_badop(ffff80001492dc18) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd802c7f1500) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd802c7f1500) at bwrite+0x206 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd802c7f1500) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff80001492dea0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8030c9f008,ffff80001492e000,ffff80001492e050,ffff80001492df30) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff8000ffff3b40,ffffff9c,7f7ffffe8e70,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff80001492e1d0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffe8e70,88,0,7f7ffffe8e94) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe8ee0, count: 4 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 fifo_badop called ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 fifo_badop(ffff80001492dc18) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd802c7f1500) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd802c7f1500) at bwrite+0x206 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd802c7f1500) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff80001492dea0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8030c9f008,ffff80001492e000,ffff80001492e050,ffff80001492df30) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff8000ffff3b40,ffffff9c,7f7ffffe8e70,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff80001492e1d0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffe8e70,88,0,7f7ffffe8e94) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe8ee0, count: -11 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001492db40 rbx 0xffff80001492dbf0 rdx 0x2 rcx 0 rax 0 r8 0xffff80001492db00 r9 0x1 r10 0 r11 0x2b9f7b50a2dff4ea r12 0x3000000008 r13 0xffff80001492db50 r14 0x100 r15 0x1 rip 0xffffffff817df538 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001492db30 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.1) pid=306023 stat=onproc flags process=2 proc=0 pri=17, usrpri=79, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff38c8,0xffff8000ffff2790 process=0xffff8000148a2a38 user=0xffff800014929000, vmspace=0xfffffd803f013000 estcpu=36, cpticks=0, pctcpu=0.1 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 80401 229119 12355 0 2 0x2 syz-executor.0 *53937 306023 12355 0 7 0x2 syz-executor.1 23722 210403 1 0 3 0x100083 ttyin getty 49073 393513 0 0 3 0x14200 acct acct 90286 189618 0 0 3 0x14200 bored sosplice 12355 169205 7046 0 3 0x82 thrsleep syz-fuzzer 12355 114109 7046 0 3 0x4000082 nanosleep syz-fuzzer 12355 140538 7046 0 3 0x4000082 kqread syz-fuzzer 12355 390340 7046 0 3 0x4000082 thrsleep syz-fuzzer 12355 517549 7046 0 3 0x4000082 thrsleep syz-fuzzer 12355 40406 7046 0 3 0x4000082 thrsleep syz-fuzzer 12355 139365 7046 0 3 0x4000082 thrsleep syz-fuzzer 12355 31729 7046 0 3 0x4000082 thrsleep syz-fuzzer 7046 272358 72740 0 3 0x10008a pause ksh 72740 19565 49539 0 3 0x92 select sshd 49539 211476 1 0 3 0x80 select sshd 79121 133880 68377 73 3 0x100090 kqread syslogd 68377 286662 1 0 3 0x100082 netio syslogd 15439 16229 1 77 3 0x100090 poll dhclient 61262 438739 1 0 3 0x80 poll dhclient 38855 31622 0 0 3 0x14200 pgzero zerothread 32547 41186 0 0 3 0x14200 aiodoned aiodoned 32061 471835 0 0 3 0x14200 syncer update 7004 40221 0 0 3 0x14200 cleaner cleaner 82858 122570 0 0 3 0x14200 reaper reaper 32377 253464 0 0 3 0x14200 pgdaemon pagedaemon 65252 447419 0 0 3 0x14200 bored crynlk 5385 176673 0 0 3 0x14200 bored crypto 10051 272687 0 0 3 0x40014200 acpi0 acpi0 39028 503835 0 0 3 0x14200 bored softnet 88299 241013 0 0 3 0x14200 bored systqmp 85423 79226 0 0 3 0x14200 bored systq 40768 252495 0 0 3 0x40014200 bored softclock 83094 339203 0 0 3 0x40014200 idle0 69498 369830 0 0 3 0x14200 bored smr 1 16107 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9528 6486K 9833K 78643K 20155 0 0 pcb 13 10K 12K 78643K 718 0 0 rtable 87 3K 4K 78643K 1776 0 0 ifaddr 56 16K 19K 78643K 499 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 120 0 0 iov 0 0K 24K 78643K 454 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1231 77K 78K 78643K 4598 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 54 0 0 VM map 12 3K 3K 78643K 20 0 0 sem 12 1K 1K 78643K 472 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 4 9K 25K 78643K 4647 0 0 sigio 0 0K 0K 78643K 60 0 0 proc 49 38K 63K 78643K 947 0 0 subproc 32 2K 2K 78643K 203 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 401 0 0 in_multi 22 1K 2K 78643K 402 0 0 ether_multi 1 0K 0K 78643K 97 0 0 mrt 0 0K 0K 78643K 38 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 108 477K 477K 78643K 108 0 0 exec 0 0K 1K 78643K 635 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 112 151K 161K 78643K 11364 0 0 UVM aobj 130 8K 8K 78643K 152 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 739 0 0 NDP 12 0K 0K 78643K 149 0 0 temp 169 3535K 3607K 78643K 41359 0 0 kqueue 0 0K 0K 78643K 26 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 84 0 80 1 0 1 1 0 8 0 rtpcb 80 267 0 265 1 0 1 1 0 8 0 rtentry 112 239 0 207 2 0 2 2 0 8 0 unpcb 120 1628 0 1608 2 1 1 2 0 8 0 syncache 264 36 0 36 5 4 1 1 0 8 1 sackhl 24 5 0 5 3 2 1 1 0 8 1 tcpqe 32 36 0 36 5 4 1 1 0 8 1 tcpcb 544 1677 0 1672 14 13 1 14 0 8 0 ipq 40 8 0 8 1 1 0 1 0 8 0 ipqe 40 16 0 16 1 1 0 1 0 8 0 inpcb 280 3900 0 3892 18 16 2 9 0 8 1 rttmr 72 5 0 5 2 2 0 1 0 8 0 nd6 48 19 0 17 1 0 1 1 0 8 0 pkpcb 40 4 0 4 1 0 1 1 0 8 1 ppxss 1128 63 0 63 7 6 1 1 0 8 1 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 705 0 533 19 4 15 15 0 8 0 art_table 32 706 0 533 2 0 2 2 0 8 0 art_node 16 228 0 199 1 0 1 1 0 8 0 sysvmsgpl 40 112 0 103 1 0 1 1 0 8 0 semupl 112 4 0 4 1 1 0 1 0 8 0 semapl 112 470 0 460 1 0 1 1 0 8 0 shmpl 112 150 0 22 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 8636 0 7240 46 0 46 46 0 8 0 ffsino 240 8636 0 7240 83 0 83 83 0 8 0 nchpl 144 14509 0 14061 60 41 19 60 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 208 5926 0 0 312 0 312 312 0 8 0 namei 1024 40903 0 40902 5 4 1 1 0 8 0 vcpupl 1984 10 0 0 2 0 2 2 0 8 0 vmpool 520 18 0 8 1 0 1 1 0 8 0 scsiplug 64 15 0 15 2 2 0 1 0 8 0 scxspl 192 42318 0 42318 10 9 1 7 0 8 1 plimitpl 152 309 0 302 1 0 1 1 0 8 0 sigapl 432 4792 0 4780 2 0 2 2 0 8 0 futexpl 56 58159 0 58159 5 4 1 1 0 8 1 knotepl 112 917 0 898 1 0 1 1 0 8 0 kqueuepl 104 1358 0 1356 4 3 1 4 0 8 0 pipepl 112 1098 0 1079 2 0 2 2 0 8 1 fdescpl 424 4793 0 4780 2 0 2 2 0 8 0 filepl 120 23785 0 23689 14 10 4 11 0 8 1 lockfpl 104 934 0 933 1 0 1 1 0 8 0 lockfspl 48 359 0 358 1 0 1 1 0 8 0 sessionpl 112 27 0 17 1 0 1 1 0 8 0 pgrppl 48 94 0 84 1 0 1 1 0 8 0 ucredpl 96 4674 0 4667 1 0 1 1 0 8 0 zombiepl 144 4780 0 4780 1 0 1 1 0 8 1 processpl 864 4809 0 4780 4 0 4 4 0 8 0 procpl 632 10019 0 9983 4 0 4 4 0 8 0 sosppl 128 44 0 44 4 3 1 1 0 8 1 sockpl 384 5821 0 5791 21 16 5 15 0 8 1 mcl64k 65536 270 0 270 14 13 1 1 0 8 1 mcl16k 16384 48 0 48 6 6 0 1 0 8 0 mcl12k 12288 48 0 48 7 6 1 1 0 8 1 mcl9k 9216 50 0 50 10 9 1 1 0 8 1 mcl8k 8192 127 0 127 9 8 1 1 0 8 1 mcl4k 4096 386 0 386 8 7 1 1 0 8 1 mcl2k2 2112 19 0 19 3 3 0 1 0 8 0 mcl2k 2048 34516 0 34476 38 29 9 11 0 8 3 mtagpl 80 249 0 199 6 3 3 3 0 8 0 mbufpl 256 124416 0 124236 63 36 27 40 0 8 7 bufpl 256 17698 0 12156 348 0 348 348 0 8 0 anonpl 16 469132 0 462772 150 111 39 54 0 62 0 amapchunkpl 152 21799 0 21721 39 29 10 13 0 158 6 amappl16 192 26985 0 26633 98 78 20 34 0 8 0 amappl15 184 194 0 192 1 0 1 1 0 8 0 amappl14 176 1707 0 1703 1 0 1 1 0 8 0 amappl13 168 9 0 8 1 0 1 1 0 8 0 amappl12 160 16 0 14 1 0 1 1 0 8 0 amappl11 152 70 0 59 1 0 1 1 0 8 0 amappl10 144 1426 0 1424 2 1 1 1 0 8 0 amappl9 136 616 0 610 1 0 1 1 0 8 0 amappl8 128 428 0 399 1 0 1 1 0 8 0 amappl7 120 1489 0 1482 1 0 1 1 0 8 0 amappl6 112 96 0 87 1 0 1 1 0 8 0 amappl5 104 733 0 722 1 0 1 1 0 8 0 amappl4 96 5076 0 5049 1 0 1 1 0 8 0 amappl3 88 1704 0 1699 1 0 1 1 0 8 0 amappl2 80 37238 0 37177 3 1 2 3 0 8 0 amappl1 72 88358 0 87962 26 16 10 20 0 8 0 amappl 80 10464 0 10426 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 151 0 22 3 0 3 3 0 8 0 uaddrrnd 24 4811 0 4780 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4811 0 4780 1 0 1 1 0 8 0 vmmpekpl 168 30375 0 30345 2 0 2 2 0 8 0 vmmpepl 168 548433 0 547119 142 70 72 79 0 357 4 vmsppl 272 4792 0 4780 3 2 1 2 0 8 0 pdppl 4096 9628 0 9586 8 2 6 7 0 8 0 pvpl 32 1321477 0 1312140 269 170 99 139 0 265 2 pmappl 200 4810 0 4788 2 0 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 624 0 126 15 0 15 15 0 8 0