panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *220634 36885 32767 0x10 0 0K syz-executor.0 443890 12524 0 0x2 0x4000000 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(ffff800024d42c48) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8065ac4000) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8065ac4000) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8065ac4000) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024d42ed0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8066486dd0,ffff800024d43030,ffff800024d43080,ffff800024d42f60) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89650,ffffff9c,7f7ffffeef20,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024d43200) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024d43200) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffeef20,88,0,7f7ffffeef44) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffeef90, 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(ffff800024d42c48) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8065ac4000) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8065ac4000) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8065ac4000) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024d42ed0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8066486dd0,ffff800024d43030,ffff800024d43080,ffff800024d42f60) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89650,ffffff9c,7f7ffffeef20,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024d43200) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024d43200) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffeef20,88,0,7f7ffffeef44) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffeef90, count: -11 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800024d42b70 rbx 0xffff800024d42c20 rdx 0xffff800020a89650 rcx 0 rax 0 r8 0xffffffff82051caf kprintf+0x16f r9 0x1 r10 0x25 r11 0x626d82eb425f5598 r12 0x3000000008 r13 0xffff800024d42b80 r14 0x100 r15 0x1 rip 0xffffffff8102dac8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800024d42b60 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=220634 stat=onproc flags process=10 proc=0 pri=17, usrpri=76, nice=20 forw=0xffffffffffffffff, list=0xffff800020a88018,0xffffffff82675500 process=0xffff800020adc380 user=0xffff800024d3e000, vmspace=0xfffffd807f00bb80 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND *36885 220634 14999 32767 7 0x10 syz-executor.0 14999 425776 12524 0 3 0x82 wait syz-executor.0 88506 517873 45897 32767 2 0x10 syz-executor.1 45897 122550 12524 0 3 0x82 wait syz-executor.1 92499 11732 0 0 3 0x14200 bored sosplice 12524 363697 12096 0 3 0x82 thrsleep syz-fuzzer 12524 186378 12096 0 3 0x4000082 nanosleep syz-fuzzer 12524 115644 12096 0 3 0x4000082 thrsleep syz-fuzzer 12524 125962 12096 0 3 0x4000082 kqread syz-fuzzer 12524 302073 12096 0 3 0x4000082 thrsleep syz-fuzzer 12524 443890 12096 0 7 0x4000002 syz-fuzzer 12524 123407 12096 0 3 0x4000082 thrsleep syz-fuzzer 12524 437332 12096 0 3 0x4000082 thrsleep syz-fuzzer 12524 48720 12096 0 3 0x4000082 thrsleep syz-fuzzer 12524 114141 12096 0 3 0x4000082 thrsleep syz-fuzzer 12096 211822 39269 0 3 0x10008a pause ksh 39269 483534 58470 0 3 0x92 select sshd 71892 24053 1 0 3 0x100083 ttyin getty 58470 382517 1 0 3 0x80 select sshd 44484 292549 91426 73 3 0x100090 kqread syslogd 91426 470554 1 0 3 0x100082 netio syslogd 46586 977 1 77 3 0x100090 poll dhclient 8566 223058 1 0 3 0x80 poll dhclient 74398 410838 0 0 3 0x14200 pgzero zerothread 472 264008 0 0 3 0x14200 aiodoned aiodoned 66126 296576 0 0 3 0x14200 syncer update 66764 458867 0 0 3 0x14200 cleaner cleaner 9033 140145 0 0 3 0x14200 reaper reaper 67867 501236 0 0 3 0x14200 pgdaemon pagedaemon 81940 264762 0 0 3 0x14200 bored crynlk 44938 74525 0 0 3 0x14200 bored crypto 53311 103586 0 0 3 0x40014200 acpi0 acpi0 51026 406679 0 0 3 0x40014200 idle1 62683 211144 0 0 3 0x14200 bored softnet 55074 43922 0 0 3 0x14200 bored systqmp 58855 223642 0 0 3 0x14200 bored systq 21772 196041 0 0 3 0x40014200 bored softclock 90947 37415 0 0 3 0x40014200 idle0 66633 327286 0 0 3 0x14200 bored smr 1 377996 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 36885 (syz-executor.0) thread 0xffff800020a89650 (220634) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82628830) #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 (0xfffffd806b4bdc58) #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 (0xfffffd806b4bd5f8) #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 Process 88506 (syz-executor.1) thread 0xffff800020a889f8 (517873) exclusive rrwlock inode r = 0 (0xfffffd806e4dd928) #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 vn_closefile+0xc7 vn_close sys/kern/vfs_vnops.c:301 [inline] #5 vn_closefile+0xc7 sys/kern/vfs_vnops.c:613 #6 fdrop+0xc2 sys/kern/kern_descrip.c:1273 #7 closef+0x11d sys/kern/kern_descrip.c:1257 #8 fdrelease+0xba sys/kern/kern_descrip.c:757 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #10 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9488 6325K 6325K 78643K 11437 0 0 pcb 13 12K 14K 78643K 17 0 0 rtable 105 3K 3K 78643K 7474 0 0 ifaddr 36 14K 15K 78643K 1089 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 406 0 0 iov 0 0K 32K 78643K 1162 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 76K 78643K 5144 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 132 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 2324 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 33K 78643K 7771 0 0 sigio 0 0K 0K 78643K 158 0 0 proc 48 50K 83K 78643K 8382 0 0 subproc 34 2K 2K 78643K 2958 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 1231 0 0 in_multi 33 2K 2K 78643K 2153 0 0 ether_multi 1 0K 0K 78643K 20 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 216 954K 954K 78643K 216 0 0 exec 0 0K 1K 78643K 3369 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 153 25K 35K 78643K 32359 0 0 UVM aobj 130 4K 4K 78643K 140 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 566 0 0 NDP 5 0K 0K 78643K 525 0 0 temp 121 3558K 3638K 78643K 39706 0 0 kqueue 0 0K 0K 78643K 132 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 64 373 0 367 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 1441 0 1439 1 0 1 1 0 8 0 rtentry 112 1788 0 1744 2 0 2 2 0 8 0 unpcb 120 7448 0 7424 22 20 2 2 0 8 1 syncache 264 70 0 70 25 24 1 1 0 8 1 tcpqe 32 21 0 21 15 15 0 1 0 8 0 tcpcb 544 9265 0 9261 85 84 1 13 0 8 0 ipq 40 92 0 92 37 36 1 1 0 8 1 ipqe 40 3556 0 3556 37 36 1 1 0 8 1 inpcb 280 18464 0 18457 109 106 3 13 0 8 2 nd6 48 348 0 344 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 7793 0 7574 14 0 14 14 0 8 0 art_table 32 7794 0 7574 2 0 2 2 0 8 0 art_node 16 1787 0 1747 1 0 1 1 0 8 0 sysvmsgpl 40 41 0 8 1 0 1 1 0 8 0 semapl 112 2322 0 2312 1 0 1 1 0 8 0 shmpl 112 138 0 10 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 9249 0 7839 46 0 46 46 0 8 0 ffsino 272 9249 0 7839 100 5 95 95 0 8 0 nchpl 144 19371 0 17755 62 1 61 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 100996 0 100995 1 0 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 57742 0 57742 58 57 1 7 0 8 1 plimitpl 152 1242 0 1233 1 0 1 1 0 8 0 sigapl 432 7426 0 7412 9 7 2 3 0 8 0 futexpl 56 165239 0 165239 1 0 1 1 0 8 1 knotepl 112 5721 0 5702 5 4 1 3 0 8 0 kqueuepl 104 3703 0 3701 14 13 1 4 0 8 0 pipepl 112 7358 0 7339 18 17 1 2 0 8 0 fdescpl 488 7427 0 7412 3 0 3 3 0 8 1 filepl 152 84049 0 83951 129 122 7 14 0 8 3 lockfpl 104 2150 0 2149 1 0 1 1 0 8 0 lockfspl 48 669 0 668 1 0 1 1 0 8 0 sessionpl 112 189 0 179 1 0 1 1 0 8 0 pgrppl 48 239 0 229 1 0 1 1 0 8 0 ucredpl 96 22951 0 22942 1 0 1 1 0 8 0 zombiepl 144 7412 0 7412 1 0 1 1 0 8 1 processpl 896 7443 0 7412 4 0 4 4 0 8 0 procpl 632 24135 0 24095 6 1 5 5 0 8 1 srpgc 64 344 0 344 46 45 1 1 0 8 1 sosppl 128 3807 0 3807 1 0 1 1 0 8 1 sockpl 384 28707 0 28674 199 191 8 22 0 8 4 mcl64k 65536 58 0 0 6 3 3 3 0 8 0 mcl16k 16384 25 0 0 4 1 3 3 0 8 0 mcl12k 12288 65 0 0 2 0 2 2 0 8 0 mcl9k 9216 26 0 0 2 1 1 2 0 8 0 mcl8k 8192 25 0 0 4 1 3 3 0 8 0 mcl4k 4096 17 0 0 3 0 3 3 0 8 0 mcl2k2 2112 11 0 0 1 0 1 1 0 8 0 mcl2k 2048 163 0 0 17 4 13 17 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 1276 0 0 24 0 24 24 0 8 0 bufpl 256 21397 0 14353 441 0 441 441 0 8 0 anonpl 16 1092294 0 1082143 232 174 58 64 0 124 0 amapchunkpl 152 79057 0 78951 158 152 6 19 0 158 0 amappl16 192 38993 0 38357 349 313 36 45 0 8 0 amappl15 184 1047 0 1047 22 22 0 1 0 8 0 amappl14 176 2145 0 2139 1 0 1 1 0 8 0 amappl13 168 897 0 897 20 20 0 1 0 8 0 amappl12 160 574 0 571 7 6 1 1 0 8 0 amappl11 152 1388 0 1377 1 0 1 1 0 8 0 amappl10 144 1250 0 1240 1 0 1 1 0 8 0 amappl9 136 3315 0 3307 1 0 1 1 0 8 0 amappl8 128 2507 0 2421 3 0 3 3 0 8 0 amappl7 120 1824 0 1814 1 0 1 1 0 8 0 amappl6 112 961 0 944 1 0 1 1 0 8 0 amappl5 104 2105 0 2095 1 0 1 1 0 8 0 amappl4 96 7494 0 7459 2 1 1 2 0 8 0 amappl3 88 1823 0 1817 1 0 1 1 0 8 0 amappl2 80 46145 0 46079 3 1 2 3 0 8 0 amappl1 72 220151 0 219739 24 14 10 20 0 8 0 amappl 80 27159 0 27123 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 64 139 0 10 3 0 3 3 0 8 0 uaddrrnd 24 7427 0 7412 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 7427 0 7412 1 0 1 1 0 8 0 vmmpekpl 168 82775 0 82747 2 0 2 2 0 8 0 vmmpepl 168 1039803 0 1038008 521 408 113 123 0 357 22 vmsppl 368 7426 0 7412 2 0 2 2 0 8 0 pdppl 4096 14861 0 14824 6 0 6 6 0 8 1 pvpl 32 2780090 0 2766770 610 477 133 160 0 265 0 pmappl 232 7426 0 7412 49 47 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 713 0 100 18 0 18 18 0 8 0