panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 76988 58683 32767 0x10 0 0K syz-executor.0 377243 63102 0 0x2 0 1 syz-fuzzer 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(ffff80002157d988) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8078250e00) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8078250e00) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8078250e00) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff80002157dc10) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd806474f750,ffff80002157dd70,ffff80002157ddc0,ffff80002157dca0) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89160,ffffff9c,7f7ffffc0ea0,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff80002157df40) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff80002157df40) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffc0ea0,88,0,7f7ffffc0ec4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc0f10, 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic fifo_badop called ddb{0}> 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(ffff80002157d988) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8078250e00) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8078250e00) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8078250e00) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff80002157dc10) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd806474f750,ffff80002157dd70,ffff80002157ddc0,ffff80002157dca0) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89160,ffffff9c,7f7ffffc0ea0,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff80002157df40) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff80002157df40) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffc0ea0,88,0,7f7ffffc0ec4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc0f10, count: -11 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80002157d8b0 rbx 0xffff80002157d960 rdx 0xffff800020a89160 rcx 0 rax 0 r8 0xffffffff815aa7ef kprintf+0x16f r9 0x1 r10 0x25 r11 0xf453485fd7b2d75f r12 0x3000000008 r13 0xffff80002157d8c0 r14 0x100 r15 0x1 rip 0xffffffff81beadb8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002157d8a0 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=76988 stat=onproc flags process=10 proc=0 pri=17, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020a89b40,0xffffffff8263f0b0 process=0xffff800020a8a710 user=0xffff800021578000, vmspace=0xfffffd807f00b5c0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND *58683 76988 86854 32767 7 0x10 syz-executor.0 86854 24578 63102 0 3 0x82 wait syz-executor.0 5554 181726 63102 0 3 0x82 wait syz-executor.1 38917 402751 0 0 3 0x14200 bored sosplice 63102 377243 73235 0 7 0x2 syz-fuzzer 63102 412716 73235 0 3 0x4000082 nanosleep syz-fuzzer 63102 323793 73235 0 3 0x4000082 thrsleep syz-fuzzer 63102 148917 73235 0 3 0x4000082 thrsleep syz-fuzzer 63102 459255 73235 0 3 0x4000082 thrsleep syz-fuzzer 63102 314476 73235 0 3 0x4000082 thrsleep syz-fuzzer 63102 145369 73235 0 3 0x4000082 thrsleep syz-fuzzer 63102 226816 73235 0 3 0x4000082 thrsleep syz-fuzzer 63102 370072 73235 0 2 0x4000002 syz-fuzzer 63102 410879 73235 0 3 0x4000082 thrsleep syz-fuzzer 73235 381072 63300 0 3 0x10008a pause ksh 63300 290200 10353 0 3 0x92 select sshd 21627 179047 1 0 3 0x100083 ttyin getty 10353 115329 1 0 3 0x80 select sshd 88715 400435 16216 73 3 0x100090 kqread syslogd 16216 295658 1 0 3 0x100082 netio syslogd 63530 400916 1 77 3 0x100090 poll dhclient 32467 134424 1 0 3 0x80 poll dhclient 35034 352358 0 0 2 0x14200 zerothread 51523 65356 0 0 3 0x14200 aiodoned aiodoned 8741 306754 0 0 3 0x14200 syncer update 49861 283316 0 0 3 0x14200 cleaner cleaner 75153 191103 0 0 3 0x14200 reaper reaper 64944 155794 0 0 3 0x14200 pgdaemon pagedaemon 80320 375278 0 0 3 0x14200 bored crynlk 89451 415284 0 0 3 0x14200 bored crypto 69160 118304 0 0 3 0x40014200 acpi0 acpi0 33630 347894 0 0 3 0x40014200 idle1 80085 161518 0 0 3 0x14200 bored softnet 67638 246113 0 0 3 0x14200 bored systqmp 91218 150091 0 0 3 0x14200 bored systq 52966 399665 0 0 3 0x40014200 bored softclock 21204 240109 0 0 3 0x40014200 idle0 60504 103312 0 0 3 0x14200 bored smr 1 416376 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 58683 (syz-executor.0) thread 0xffff800020a89160 (76988) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8264d188) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 __mp_acquire_count+0x51 sys/kern/kern_lock.c:227 #2 mi_switch+0x392 sys/kern/sched_bsd.c:436 #3 sleep_finish+0x113 sys/kern/kern_synch.c:373 #4 tsleep+0x198 sleep_finish_timeout sys/kern/kern_synch.c:397 [inline] #4 tsleep+0x198 sleep_finish_all sys/kern/kern_synch.c:183 [inline] #4 tsleep+0x198 sys/kern/kern_synch.c:152 #5 biowait+0xa1 sys/kern/vfs_bio.c:1231 #6 bwrite+0x1e4 sys/kern/vfs_bio.c:747 #7 ffs_update+0x2c2 sys/ufs/ffs/ffs_inode.c:113 #8 ufs_mkdir+0x665 sys/ufs/ufs/ufs_vnops.c:1234 #9 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #10 domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 #11 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #11 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #12 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd8063e79a28) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:574 #5 vget+0x1c3 sys/kern/vfs_subr.c:672 #6 ufs_ihashget+0x141 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x74 sys/ufs/ffs/ffs_vfsops.c:1323 #8 ffs_inode_alloc+0x1cf sys/ufs/ffs/ffs_alloc.c:392 #9 ufs_mkdir+0xf4 sys/ufs/ufs/ufs_vnops.c:1164 #10 VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 #11 domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 #12 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #12 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #13 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806e4c55f8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:574 #5 vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419 #6 namei+0x63c sys/kern/vfs_lookup.c:249 #7 domkdirat+0x75 sys/kern/vfs_syscalls.c:2968 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #9 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9471 6323K 6323K 78643K 14888 0 0 pcb 13 10K 12K 78643K 15 0 0 rtable 117 3K 3K 78643K 35029 0 0 ifaddr 36 22K 29K 78643K 5760 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 984 0 0 iov 0 0K 32K 78643K 1411 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 76K 78643K 16327 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 47 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 1K 78643K 1154 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 33K 78643K 16758 0 0 sigio 0 0K 0K 78643K 89 0 0 proc 48 50K 83K 78643K 35496 0 0 subproc 34 2K 2K 78643K 14756 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 428 0 0 in_multi 33 2K 2K 78643K 9656 0 0 ether_multi 1 0K 0K 78643K 5 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 114 503K 503K 78643K 114 0 0 exec 0 0K 1K 78643K 11825 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 123 23K 32K 78643K 55749 0 0 UVM aobj 130 5K 5K 78643K 135 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 183 0 0 NDP 9 0K 0K 78643K 2607 0 0 temp 121 3562K 3642K 78643K 133780 0 0 kqueue 0 0K 0K 78643K 50 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 1749 0 1743 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 2046 0 2044 1 0 1 1 0 8 0 rtentry 112 8725 0 8675 2 0 2 2 0 8 0 unpcb 120 2140 0 2125 3 2 1 2 0 8 0 syncache 264 28 0 28 14 14 0 1 0 8 0 tcpqe 32 87 0 87 5 5 0 1 0 8 0 tcpcb 544 1399 0 1395 19 18 1 12 0 8 0 ipq 40 43 0 43 19 19 0 1 0 8 0 ipqe 40 1439 0 1439 19 19 0 1 0 8 0 inpcb 280 7705 0 7698 49 48 1 9 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 ip6af 40 3 0 3 1 1 0 1 0 8 0 nd6 48 1739 0 1735 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 42140 0 41839 30 11 19 20 0 8 0 art_table 32 42141 0 41839 8 5 3 3 0 8 0 art_node 16 8724 0 8678 1 0 1 1 0 8 0 sysvmsgpl 40 42 0 26 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 1152 0 1142 1 0 1 1 0 8 0 shmpl 112 133 0 5 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 7091 0 5684 46 0 46 46 0 8 0 ffsino 272 7091 0 5684 96 2 94 95 0 8 0 nchpl 144 16274 0 14662 61 1 60 61 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 155803 0 155802 1 0 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 41377 0 41377 52 51 1 7 0 8 1 plimitpl 152 2145 0 2136 1 0 1 1 0 8 0 sigapl 432 14331 0 14317 30 27 3 3 0 8 1 futexpl 56 73720 0 73720 1 0 1 1 0 8 1 knotepl 112 19846 0 19827 4 3 1 2 0 8 0 kqueuepl 104 1509 0 1507 8 7 1 4 0 8 0 pipepl 112 15448 0 15429 76 75 1 6 0 8 0 fdescpl 488 14332 0 14317 4 1 3 3 0 8 0 filepl 152 74777 0 74679 110 105 5 13 0 8 1 lockfpl 104 690 0 689 1 0 1 1 0 8 0 lockfspl 48 258 0 257 1 0 1 1 0 8 0 sessionpl 112 883 0 873 1 0 1 1 0 8 0 pgrppl 48 901 0 891 1 0 1 1 0 8 0 ucredpl 96 7549 0 7540 1 0 1 1 0 8 0 zombiepl 144 14318 0 14317 1 0 1 1 0 8 0 processpl 896 14348 0 14317 4 0 4 4 0 8 0 procpl 632 19938 0 19898 43 39 4 5 0 8 0 srpgc 64 1732 0 1732 1 0 1 1 0 8 1 sosppl 128 73 0 73 25 25 0 1 0 8 0 sockpl 384 11945 0 11921 43 39 4 14 0 8 0 mcl64k 65536 34 0 0 4 1 3 3 0 8 0 mcl16k 16384 28 0 0 4 2 2 3 0 8 0 mcl12k 12288 31 0 0 2 0 2 2 0 8 0 mcl9k 9216 19 0 0 2 0 2 2 0 8 0 mcl8k 8192 34 0 0 4 2 2 3 0 8 0 mcl4k 4096 25 0 0 4 1 3 3 0 8 0 mcl2k2 2112 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 171 0 0 18 0 18 18 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 925 0 0 19 0 19 19 0 8 0 bufpl 256 16230 0 9186 441 0 441 441 0 8 0 anonpl 16 1111166 0 1102411 181 133 48 53 0 124 0 amapchunkpl 152 168532 0 168433 91 81 10 18 0 158 4 amappl16 192 29369 0 28805 174 141 33 40 0 8 0 amappl15 184 1146 0 1145 1 0 1 1 0 8 0 amappl14 176 6886 0 6876 1 0 1 1 0 8 0 amappl13 168 835 0 833 1 0 1 1 0 8 0 amappl12 160 980 0 976 4 3 1 1 0 8 0 amappl11 152 3619 0 3608 1 0 1 1 0 8 0 amappl10 144 1601 0 1596 1 0 1 1 0 8 0 amappl9 136 12706 0 12700 1 0 1 1 0 8 0 amappl8 128 9453 0 9401 2 0 2 2 0 8 0 amappl7 120 4336 0 4327 1 0 1 1 0 8 0 amappl6 112 1351 0 1337 1 0 1 1 0 8 0 amappl5 104 6788 0 6779 1 0 1 1 0 8 0 amappl4 96 14584 0 14555 1 0 1 1 0 8 0 amappl3 88 897 0 888 1 0 1 1 0 8 0 amappl2 80 44757 0 44692 3 1 2 3 0 8 0 amappl1 72 465676 0 465255 24 14 10 20 0 8 0 amappl 80 33423 0 33389 1 0 1 1 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 64 134 0 5 3 0 3 3 0 8 0 uaddrrnd 24 14332 0 14317 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 14332 0 14317 1 0 1 1 0 8 0 vmmpekpl 168 135053 0 135025 2 0 2 2 0 8 0 vmmpepl 168 2037860 0 2036171 301 199 102 116 0 357 25 vmsppl 368 14331 0 14317 2 0 2 2 0 8 0 pdppl 4096 28671 0 28634 7 1 6 6 0 8 1 pvpl 32 4217972 0 4206016 471 350 121 142 0 265 1 pmappl 232 14331 0 14317 11 9 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 655 0 40 18 0 18 18 0 8 0