panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *215240 21820 0 0x2 0 0 syz-executor.0 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(ffff800014931d78) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd802f49d600) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd802f49d600) at bwrite+0x206 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd802f49d600) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800014932000) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd802c1ae418,ffff800014932160,ffff8000149321b0,ffff800014932090) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff8000ffff2290,ffffff9c,7f7fffff5ad0,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800014932330) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7fffff5ad0,88,0,7f7fffff5af4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff5b40, 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(ffff800014931d78) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd802f49d600) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd802f49d600) at bwrite+0x206 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd802f49d600) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800014932000) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd802c1ae418,ffff800014932160,ffff8000149321b0,ffff800014932090) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff8000ffff2290,ffffff9c,7f7fffff5ad0,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800014932330) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7fffff5ad0,88,0,7f7fffff5af4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff5b40, count: -11 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014931ca0 rbx 0xffff800014931d50 rdx 0x2 rcx 0 rax 0 r8 0xffff800014931c60 r9 0x1 r10 0 r11 0x4c53dae6910c6186 r12 0x3000000008 r13 0xffff800014931cb0 r14 0x100 r15 0x1 rip 0xffffffff81544c98 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014931c90 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.0) pid=215240 stat=onproc flags process=2 proc=0 pri=17, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff2780,0xffffffff825885c0 process=0xffff8000ffff7450 user=0xffff80001492d000, vmspace=0xfffffd803f014220 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND *21820 215240 63333 0 7 0x2 syz-executor.0 84356 383259 63333 0 2 0x2 syz-executor.1 43279 356516 0 0 3 0x14200 acct acct 65105 303704 0 0 3 0x14200 bored sosplice 63333 224780 42963 0 3 0x82 thrsleep syz-fuzzer 63333 453301 42963 0 3 0x4000082 nanosleep syz-fuzzer 63333 218749 42963 0 3 0x4000082 thrsleep syz-fuzzer 63333 100331 42963 0 3 0x4000082 thrsleep syz-fuzzer 63333 153760 42963 0 3 0x4000082 thrsleep syz-fuzzer 63333 463982 42963 0 3 0x4000082 kqread syz-fuzzer 63333 522245 42963 0 3 0x4000082 thrsleep syz-fuzzer 42963 138187 16437 0 3 0x10008a pause ksh 16437 276786 4610 0 3 0x92 select sshd 14289 296796 1 0 3 0x100083 ttyin getty 4610 500650 1 0 3 0x80 select sshd 62454 519200 82946 73 3 0x100090 kqread syslogd 82946 493289 1 0 3 0x100082 netio syslogd 21180 270935 1 77 3 0x100090 poll dhclient 60738 166063 1 0 3 0x80 poll dhclient 74173 236981 0 0 3 0x14200 pgzero zerothread 75286 118076 0 0 3 0x14200 aiodoned aiodoned 29513 425779 0 0 3 0x14200 syncer update 58262 88240 0 0 3 0x14200 cleaner cleaner 88924 275668 0 0 3 0x14200 reaper reaper 71752 237385 0 0 3 0x14200 pgdaemon pagedaemon 57383 171461 0 0 3 0x14200 bored crynlk 82806 498628 0 0 3 0x14200 bored crypto 22500 99356 0 0 3 0x40014200 acpi0 acpi0 37984 459165 0 0 3 0x14200 bored softnet 75008 325270 0 0 3 0x14200 bored systqmp 67025 440399 0 0 3 0x14200 bored systq 89513 262339 0 0 3 0x40014200 bored softclock 20272 9167 0 0 3 0x40014200 idle0 14312 7557 0 0 3 0x14200 bored smr 1 371487 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 9561 7181K 7699K 78643K 15304 0 0 pcb 13 8K 9K 78643K 645 0 0 rtable 119 8K 8K 78643K 1582 0 0 ifaddr 75 16K 17K 78643K 382 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 109 0 0 iov 0 0K 32K 78643K 384 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1214 76K 77K 78643K 2936 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 27 0 0 VM map 27 6K 6K 78643K 34 0 0 sem 12 0K 0K 78643K 512 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 4 9K 25K 78643K 1765 0 0 sigio 0 0K 0K 78643K 38 0 0 proc 49 38K 55K 78643K 994 0 0 subproc 32 2K 2K 78643K 242 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 181 0 0 in_multi 34 2K 2K 78643K 210 0 0 ether_multi 1 0K 0K 78643K 9 0 0 mrt 0 0K 0K 78643K 141 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 102 450K 450K 78643K 102 0 0 exec 0 0K 1K 78643K 542 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 143 233K 234K 78643K 5275 0 0 UVM aobj 130 4K 4K 78643K 132 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 360 0 0 NDP 21 1K 1K 78643K 121 0 0 temp 205 3544K 4184K 78643K 103057 0 0 kqueue 0 0K 0K 78643K 13 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 50 0 44 1 0 1 1 0 8 0 rtpcb 80 898 0 896 1 0 1 1 0 8 0 rtentry 112 292 0 247 2 0 2 2 0 8 0 unpcb 120 1165 0 1156 2 1 1 2 0 8 0 syncache 264 14 0 14 5 5 0 1 0 8 0 tcpqe 32 99 0 99 3 3 0 1 0 8 0 tcpcb 544 2141 0 2137 8 6 2 3 0 8 1 ipq 40 6 0 6 3 3 0 1 0 8 0 ipqe 40 143 0 143 3 3 0 1 0 8 0 inpcb 280 3702 0 3695 7 5 2 4 0 8 1 rttmr 72 60 0 59 1 0 1 1 0 8 0 nd6 48 30 0 26 2 1 1 1 0 8 0 pkpcb 40 5 0 5 3 3 0 1 0 8 0 ppxss 1128 43 0 43 5 4 1 1 0 8 1 art_heap8 4096 3 0 2 3 2 1 3 0 8 0 art_heap4 256 935 0 695 26 10 16 16 0 8 1 art_table 32 938 0 697 4 1 3 3 0 8 1 art_node 16 291 0 250 1 0 1 1 0 8 0 sysvmsgpl 40 68 0 53 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 504 0 494 1 0 1 1 0 8 0 shmpl 112 130 0 2 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 4073 0 2671 46 0 46 46 0 8 0 ffsino 240 4073 0 2671 83 0 83 83 0 8 0 nchpl 144 7159 0 6686 60 41 19 60 0 8 0 uvmvnodes 72 5371 0 0 98 0 98 98 0 8 0 vnodes 208 5371 0 0 283 0 283 283 0 8 0 namei 1024 23955 0 23954 1 0 1 1 0 8 0 vcpupl 1984 25 0 0 4 0 4 4 0 8 0 vmpool 520 32 0 7 2 0 2 2 0 8 0 scsiplug 64 1 0 1 1 1 0 1 0 8 0 scxspl 192 22344 0 22344 12 11 1 7 0 8 1 plimitpl 152 176 0 169 1 0 1 1 0 8 0 sigapl 432 1900 0 1888 2 0 2 2 0 8 0 futexpl 56 57373 0 57373 1 0 1 1 0 8 1 knotepl 112 586 0 567 4 3 1 3 0 8 0 kqueuepl 104 484 0 482 1 0 1 1 0 8 0 pipepl 112 1414 0 1395 8 7 1 2 0 8 0 fdescpl 424 1901 0 1888 2 0 2 2 0 8 0 filepl 120 17805 0 17709 10 6 4 6 0 8 1 lockfpl 104 665 0 664 1 0 1 1 0 8 0 lockfspl 48 225 0 224 1 0 1 1 0 8 0 sessionpl 112 29 0 19 1 0 1 1 0 8 0 pgrppl 48 49 0 39 1 0 1 1 0 8 0 ucredpl 96 2656 0 2649 1 0 1 1 0 8 0 zombiepl 144 1888 0 1888 1 0 1 1 0 8 1 processpl 864 1917 0 1888 4 0 4 4 0 8 0 procpl 632 3954 0 3919 4 0 4 4 0 8 0 sosppl 128 33 0 33 6 6 0 1 0 8 0 sockpl 384 5801 0 5783 14 10 4 7 0 8 1 mcl64k 65536 147 0 147 2 1 1 1 0 8 1 mcl16k 16384 31 0 31 6 5 1 1 0 8 1 mcl12k 12288 52 0 52 4 3 1 1 0 8 1 mcl9k 9216 39 0 39 4 3 1 1 0 8 1 mcl8k 8192 100 0 100 3 2 1 1 0 8 1 mcl4k 4096 191 0 191 2 1 1 1 0 8 1 mcl2k2 2112 18 0 18 7 7 0 1 0 8 0 mcl2k 2048 70838 0 70794 17 10 7 14 0 8 1 mtagpl 80 98 0 98 2 1 1 1 0 8 1 mbufpl 256 130924 0 130823 37 24 13 19 0 8 2 bufpl 256 11493 0 6385 320 0 320 320 0 8 0 anonpl 16 239179 0 224031 138 55 83 97 0 62 2 amapchunkpl 152 9529 0 9420 13 6 7 10 0 158 0 amappl16 192 11216 0 10068 111 51 60 68 0 8 1 amappl15 184 713 0 711 3 2 1 1 0 8 0 amappl14 176 125 0 123 1 0 1 1 0 8 0 amappl13 168 178 0 178 1 1 0 1 0 8 0 amappl12 160 120 0 117 1 0 1 1 0 8 0 amappl11 152 211 0 200 1 0 1 1 0 8 0 amappl10 144 169 0 167 1 0 1 1 0 8 0 amappl9 136 794 0 788 1 0 1 1 0 8 0 amappl8 128 341 0 304 3 1 2 2 0 8 0 amappl7 120 247 0 238 1 0 1 1 0 8 0 amappl6 112 219 0 205 1 0 1 1 0 8 0 amappl5 104 362 0 351 1 0 1 1 0 8 0 amappl4 96 2317 0 2289 1 0 1 1 0 8 0 amappl3 88 250 0 238 1 0 1 1 0 8 0 amappl2 80 14056 0 13991 3 1 2 3 0 8 0 amappl1 72 45508 0 45113 26 17 9 20 0 8 0 amappl 80 4394 0 4345 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 64 131 0 2 3 0 3 3 0 8 0 uaddrrnd 24 1933 0 1888 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1933 0 1888 1 0 1 1 0 8 0 vmmpekpl 168 16101 0 16073 2 0 2 2 0 8 0 vmmpepl 168 241695 0 239470 224 74 150 166 0 357 41 vmsppl 272 1900 0 1888 3 1 2 2 0 8 1 pdppl 4096 3872 0 3815 9 1 8 8 0 8 0 pvpl 32 630014 0 612672 273 75 198 217 0 265 15 pmappl 200 1932 0 1895 4 1 3 3 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 525 0 65 14 0 14 14 0 8 0