panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *407719 65204 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(ffff80001490fd38) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd803465b000) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd803465b000) at bwrite+0x206 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd803465b000) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff80001490ffc0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd803eb7b340,ffff800014910120,ffff800014910170,ffff800014910050) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800015944788,ffffff9c,7f7ffffd2d10,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff8000149102f0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffd2d10,88,0,7f7ffffd2d34) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd2d80, 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(ffff80001490fd38) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd803465b000) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd803465b000) at bwrite+0x206 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd803465b000) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff80001490ffc0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd803eb7b340,ffff800014910120,ffff800014910170,ffff800014910050) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800015944788,ffffff9c,7f7ffffd2d10,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff8000149102f0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffd2d10,88,0,7f7ffffd2d34) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd2d80, count: -11 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001490fc60 rbx 0xffff80001490fd10 rdx 0x2 rcx 0 rax 0 r8 0xffff80001490fc20 r9 0x1 r10 0 r11 0x2fd276accf9ee562 r12 0x3000000008 r13 0xffff80001490fc70 r14 0x100 r15 0x1 rip 0xffffffff815c9928 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001490fc50 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.1) pid=407719 stat=onproc flags process=2 proc=0 pri=17, usrpri=79, nice=20 forw=0xffffffffffffffff, list=0xffff800015944c78,0xffff800015944f00 process=0xffff8000ffff66d0 user=0xffff80001490b000, vmspace=0xfffffd803f014110 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 24282 290832 43246 0 2 0x2 syz-executor.0 *65204 407719 43246 0 7 0x2 syz-executor.1 31394 431881 0 0 3 0x14200 bored sosplice 43246 377400 96242 0 3 0x82 thrsleep syz-fuzzer 43246 457172 96242 0 3 0x4000082 nanosleep syz-fuzzer 43246 5940 96242 0 3 0x4000082 thrsleep syz-fuzzer 43246 281586 96242 0 3 0x4000082 thrsleep syz-fuzzer 43246 320114 96242 0 3 0x4000082 thrsleep syz-fuzzer 43246 462057 96242 0 3 0x4000082 kqread syz-fuzzer 43246 122338 96242 0 3 0x4000082 thrsleep syz-fuzzer 43246 235730 96242 0 3 0x4000082 thrsleep syz-fuzzer 96242 161496 24289 0 3 0x10008a pause ksh 24289 182569 76006 0 3 0x92 select sshd 3539 298768 1 0 3 0x100083 ttyin getty 76006 339232 1 0 3 0x80 select sshd 12357 223897 87163 73 3 0x100090 kqread syslogd 87163 198810 1 0 3 0x100082 netio syslogd 66626 159612 1 77 3 0x100090 poll dhclient 42121 21783 1 0 3 0x80 poll dhclient 28812 289886 0 0 3 0x14200 pgzero zerothread 70197 155796 0 0 3 0x14200 aiodoned aiodoned 62261 437711 0 0 3 0x14200 syncer update 46260 273570 0 0 3 0x14200 cleaner cleaner 32033 147984 0 0 3 0x14200 reaper reaper 86393 404069 0 0 3 0x14200 pgdaemon pagedaemon 67152 480952 0 0 3 0x14200 bored crynlk 33678 336959 0 0 3 0x14200 bored crypto 21149 108637 0 0 3 0x40014200 acpi0 acpi0 6223 443262 0 0 3 0x14200 bored softnet 84064 278926 0 0 3 0x14200 bored systqmp 19516 256558 0 0 3 0x14200 bored systq 9770 437472 0 0 3 0x40014200 bored softclock 13544 378461 0 0 3 0x40014200 idle0 7848 42634 0 0 3 0x14200 bored smr 1 173343 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 9463 6329K 7879K 78643K 14122 0 0 pcb 13 14K 18K 78643K 213 0 0 rtable 111 4K 4K 78643K 552 0 0 ifaddr 44 11K 12K 78643K 132 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 159 0 0 iov 0 0K 24K 78643K 147 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1216 76K 77K 78643K 2658 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 9K 78643K 47 0 0 VM map 22 5K 5K 78643K 22 0 0 sem 12 0K 1K 78643K 516 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 4 9K 25K 78643K 2067 0 0 sigio 0 0K 0K 78643K 11 0 0 proc 48 38K 63K 78643K 666 0 0 subproc 32 2K 2K 78643K 85 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 316 0 0 in_multi 33 2K 2K 78643K 79 0 0 ether_multi 1 0K 0K 78643K 8 0 0 mrt 0 0K 0K 78643K 7 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 60 265K 265K 78643K 60 0 0 exec 0 0K 1K 78643K 296 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 117 184K 185K 78643K 5504 0 0 UVM aobj 128 3K 3K 78643K 164 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 206 0 0 NDP 9 0K 0K 78643K 39 0 0 temp 135 3538K 3630K 78643K 147310 0 0 kqueue 0 0K 0K 78643K 8 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 15 0 9 1 0 1 1 0 8 0 rtpcb 80 147 0 145 1 0 1 1 0 8 0 rtentry 112 80 0 36 2 0 2 2 0 8 0 unpcb 120 869 0 861 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 sackhl 24 13 0 13 5 4 1 1 0 8 1 tcpqe 32 1 0 1 1 1 0 1 0 8 0 tcpcb 544 3329 0 3325 17 13 4 15 0 8 3 ipq 40 7 0 7 1 1 0 1 0 8 0 ipqe 40 315 0 315 1 1 0 1 0 8 0 inpcb 280 4771 0 4764 20 15 5 16 0 8 4 nd6 48 10 0 6 1 0 1 1 0 8 0 ppxss 1128 11 0 11 2 2 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 356 0 141 14 0 14 14 0 8 0 art_table 32 357 0 141 2 0 2 2 0 8 0 art_node 16 79 0 39 1 0 1 1 0 8 0 sysvmsgpl 40 49 0 25 1 0 1 1 0 8 0 semapl 112 514 0 504 1 0 1 1 0 8 0 shmpl 112 162 0 36 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 4760 0 3367 46 0 46 46 0 8 0 ffsino 240 4760 0 3367 83 0 83 83 0 8 0 nchpl 144 7796 0 6199 60 0 60 60 0 8 0 uvmvnodes 72 5639 0 0 103 0 103 103 0 8 0 vnodes 208 5639 0 0 297 0 297 297 0 8 0 namei 1024 21206 0 21205 2 1 1 1 0 8 0 vcpupl 1984 20 0 0 3 0 3 3 0 8 0 vmpool 520 20 0 0 2 0 2 2 0 8 0 scsiplug 64 7 0 7 1 1 0 1 0 8 0 scxspl 192 24625 0 24625 8 7 1 7 0 8 1 plimitpl 152 111 0 104 1 0 1 1 0 8 0 sigapl 432 2229 0 2217 2 0 2 2 0 8 0 futexpl 56 38385 0 38385 1 0 1 1 0 8 1 knotepl 112 461 0 442 1 0 1 1 0 8 0 kqueuepl 104 3114 0 3112 7 5 2 7 0 8 1 pipepl 112 652 0 633 2 1 1 1 0 8 0 fdescpl 424 2230 0 2217 2 0 2 2 0 8 0 filepl 120 17772 0 17676 17 11 6 17 0 8 3 lockfpl 104 469 0 468 1 0 1 1 0 8 0 lockfspl 48 182 0 181 1 0 1 1 0 8 0 sessionpl 112 20 0 10 1 0 1 1 0 8 0 pgrppl 48 20 0 10 1 0 1 1 0 8 0 ucredpl 96 2514 0 2507 1 0 1 1 0 8 0 zombiepl 144 2217 0 2217 2 1 1 1 0 8 1 processpl 864 2245 0 2217 4 0 4 4 0 8 0 procpl 632 4612 0 4577 5 1 4 5 0 8 0 sosppl 128 45 0 45 3 2 1 1 0 8 1 sockpl 384 5792 0 5775 27 21 6 24 0 8 4 mcl64k 65536 62 0 62 2 2 0 1 0 8 0 mcl16k 16384 51 0 51 1 1 0 1 0 8 0 mcl12k 12288 36 0 36 2 2 0 1 0 8 0 mcl9k 9216 10 0 10 1 1 0 1 0 8 0 mcl8k 8192 105 0 105 3 2 1 1 0 8 1 mcl4k 4096 177 0 177 6 5 1 1 0 8 1 mcl2k 2048 17783 0 17751 14 8 6 8 0 8 1 mtagpl 80 169 0 128 6 3 3 3 0 8 1 mbufpl 256 60087 0 59949 40 15 25 25 0 8 6 bufpl 256 12248 0 7337 312 4 308 308 0 8 0 anonpl 16 195940 0 192435 48 15 33 33 0 62 17 amapchunkpl 152 9244 0 9161 15 10 5 9 0 158 1 amappl16 192 12142 0 11983 26 9 17 21 0 8 8 amappl15 184 556 0 555 1 0 1 1 0 8 0 amappl14 176 50 0 44 2 1 1 1 0 8 0 amappl13 168 1 0 1 1 1 0 1 0 8 0 amappl12 160 441 0 439 1 0 1 1 0 8 0 amappl11 152 50 0 39 1 0 1 1 0 8 0 amappl10 144 7 0 7 1 1 0 1 0 8 0 amappl9 136 270 0 264 1 0 1 1 0 8 0 amappl8 128 187 0 157 2 0 2 2 0 8 0 amappl7 120 55 0 49 1 0 1 1 0 8 0 amappl6 112 97 0 86 1 0 1 1 0 8 0 amappl5 104 1318 0 1307 1 0 1 1 0 8 0 amappl4 96 2068 0 2042 1 0 1 1 0 8 0 amappl3 88 610 0 602 1 0 1 1 0 8 0 amappl2 80 17493 0 17433 3 1 2 3 0 8 0 amappl1 72 47792 0 47399 25 14 11 20 0 8 0 amappl 80 4897 0 4854 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 64 163 0 36 3 0 3 3 0 8 0 uaddrrnd 24 2250 0 2217 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2250 0 2217 1 0 1 1 0 8 0 vmmpekpl 168 15512 0 15484 2 0 2 2 0 8 0 vmmpepl 168 257210 0 256069 105 34 71 77 0 357 12 vmsppl 272 2229 0 2217 3 2 1 2 0 8 0 pdppl 4096 4506 0 4454 9 1 8 8 0 8 1 pvpl 32 658493 0 652042 163 69 94 115 0 265 37 pmappl 200 2249 0 2217 2 0 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 512 0 56 14 0 14 14 0 8 0