panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *498015 32736 32767 0x10 0 1K syz-executor.1 397262 95338 32767 0x10 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(ffff800024d53818) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd80686f8300) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd80686f8300) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd80686f8300) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024d53aa0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8064a20838,ffff800024d53c00,ffff800024d53c50,ffff800024d53b30) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020ace020,ffffff9c,7f7ffffe0540,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024d53dd0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024d53dd0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffe0540,88,0,7f7ffffe0564) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe05b0, 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic fifo_badop called ddb{1}> 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(ffff800024d53818) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd80686f8300) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd80686f8300) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd80686f8300) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024d53aa0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8064a20838,ffff800024d53c00,ffff800024d53c50,ffff800024d53b30) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020ace020,ffffff9c,7f7ffffe0540,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024d53dd0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024d53dd0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffe0540,88,0,7f7ffffe0564) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe05b0, count: -11 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800024d53740 rbx 0xffff800024d537f0 rdx 0xffff800020ace020 rcx 0 rax 0 r8 0xffffffff820e3b9f kprintf+0x16f r9 0x1 r10 0x25 r11 0xb40faf97671b02fb r12 0x3000000008 r13 0xffff800024d53750 r14 0x100 r15 0x1 rip 0xffffffff81634f28 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800024d53730 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=498015 stat=onproc flags process=10 proc=0 pri=17, usrpri=53, nice=20 forw=0xffffffffffffffff, list=0xffff800020acea00,0xffffffff8262a918 process=0xffff800020a8a710 user=0xffff800024d4e000, vmspace=0xfffffd807f00b730 estcpu=36, cpticks=2, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *32736 498015 68161 32767 7 0x10 syz-executor.1 68161 386475 85762 0 3 0x82 wait syz-executor.1 95338 397262 7880 32767 7 0x10 syz-executor.0 7880 188109 85762 0 3 0x82 wait syz-executor.0 39486 38412 0 0 3 0x14200 bored sosplice 85762 477996 58366 0 2 0x2 syz-fuzzer 85762 295633 58366 0 3 0x4000082 nanosleep syz-fuzzer 85762 385796 58366 0 3 0x4000082 thrsleep syz-fuzzer 85762 265510 58366 0 3 0x4000082 kqread syz-fuzzer 85762 18705 58366 0 3 0x4000082 thrsleep syz-fuzzer 85762 334942 58366 0 3 0x4000082 thrsleep syz-fuzzer 85762 25269 58366 0 3 0x4000082 thrsleep syz-fuzzer 85762 442242 58366 0 3 0x4000082 thrsleep syz-fuzzer 85762 158334 58366 0 3 0x4000082 thrsleep syz-fuzzer 85762 124085 58366 0 3 0x4000082 thrsleep syz-fuzzer 58366 261353 33519 0 3 0x10008a pause ksh 33519 52065 43680 0 3 0x92 select sshd 92242 218065 1 0 3 0x100083 ttyin getty 43680 391863 1 0 3 0x80 select sshd 27312 487925 22540 73 3 0x100090 kqread syslogd 22540 469835 1 0 3 0x100082 netio syslogd 80798 494913 1 77 3 0x100090 poll dhclient 99657 388047 1 0 3 0x80 poll dhclient 12304 227118 0 0 3 0x14200 pgzero zerothread 49010 407405 0 0 3 0x14200 aiodoned aiodoned 98599 120776 0 0 3 0x14200 syncer update 78598 442434 0 0 3 0x14200 cleaner cleaner 9954 66697 0 0 3 0x14200 reaper reaper 57933 430455 0 0 3 0x14200 pgdaemon pagedaemon 53911 511375 0 0 3 0x14200 bored crynlk 22364 167833 0 0 3 0x14200 bored crypto 87403 443059 0 0 3 0x40014200 acpi0 acpi0 20662 129261 0 0 3 0x40014200 idle1 20991 308378 0 0 3 0x14200 bored softnet 68865 133335 0 0 3 0x14200 bored systqmp 3830 304118 0 0 3 0x14200 bored systq 53032 483794 0 0 3 0x40014200 bored softclock 88363 200957 0 0 3 0x40014200 idle0 57060 77651 0 0 3 0x14200 bored smr 1 276293 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 32736 (syz-executor.1) thread 0xffff800020ace020 (498015) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82677670) #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 (0xfffffd80667b96f8) #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 (0xfffffd80667b9808) #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 95338 (syz-executor.0) thread 0xffff800020ace788 (397262) exclusive rrwlock inode r = 0 (0xfffffd806e40f1a8) #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{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9470 6322K 6322K 78643K 10692 0 0 pcb 13 10K 12K 78643K 15 0 0 rtable 105 3K 3K 78643K 1325 0 0 ifaddr 35 10K 10K 78643K 203 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 53 0 0 iov 0 0K 32K 78643K 199 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 76K 78643K 1997 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 18 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 450 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 33K 78643K 1157 0 0 sigio 0 0K 0K 78643K 8 0 0 proc 48 50K 71K 78643K 1628 0 0 subproc 34 2K 2K 78643K 493 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 121 0 0 in_multi 33 2K 2K 78643K 362 0 0 ether_multi 1 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 108 477K 477K 78643K 108 0 0 exec 0 0K 1K 78643K 645 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 104 22K 23K 78643K 5645 0 0 UVM aobj 130 4K 4K 78643K 130 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 54 0 0 NDP 7 0K 0K 78643K 90 0 0 temp 120 3554K 3622K 78643K 8730 0 0 kqueue 0 0K 0K 78643K 14 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 60 0 54 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 178 0 176 1 0 1 1 0 8 0 rtentry 112 315 0 271 2 0 2 2 0 8 0 unpcb 120 995 0 985 1 0 1 1 0 8 0 syncache 264 8 0 8 4 4 0 1 0 8 0 tcpqe 32 4 0 4 2 2 0 1 0 8 0 tcpcb 544 773 0 769 25 24 1 14 0 8 0 ipq 40 7 0 7 2 2 0 1 0 8 0 ipqe 40 315 0 315 2 2 0 1 0 8 0 inpcb 280 1541 0 1534 24 21 3 9 0 8 2 nd6 48 58 0 54 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1395 0 1176 14 0 14 14 0 8 0 art_table 32 1396 0 1176 2 0 2 2 0 8 0 art_node 16 314 0 274 1 0 1 1 0 8 0 sysvmsgpl 40 73 0 52 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 448 0 438 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 2723 0 1321 46 0 46 46 0 8 0 ffsino 272 2723 0 1321 94 0 94 94 0 8 0 nchpl 144 4254 0 2655 60 0 60 60 0 8 0 uvmvnodes 72 3225 0 0 59 0 59 59 0 8 0 vnodes 208 3225 0 0 170 0 170 170 0 8 0 namei 1024 19043 0 19042 2 1 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 12433 0 12433 15 14 1 7 0 8 1 plimitpl 152 191 0 182 1 0 1 1 0 8 0 sigapl 432 1247 0 1233 3 1 2 3 0 8 0 futexpl 56 21983 0 21983 2 1 1 1 0 8 1 knotepl 112 936 0 917 4 3 1 3 0 8 0 kqueuepl 104 666 0 664 7 6 1 4 0 8 0 pipepl 112 918 0 899 2 1 1 2 0 8 0 fdescpl 488 1248 0 1233 3 0 3 3 0 8 1 filepl 152 12626 0 12528 28 22 6 14 0 8 2 lockfpl 104 174 0 173 1 0 1 1 0 8 0 lockfspl 48 71 0 70 1 0 1 1 0 8 0 sessionpl 112 44 0 34 1 0 1 1 0 8 0 pgrppl 48 44 0 34 1 0 1 1 0 8 0 ucredpl 96 3841 0 3832 1 0 1 1 0 8 0 zombiepl 144 1233 0 1233 1 0 1 1 0 8 1 processpl 896 1264 0 1233 4 0 4 4 0 8 0 procpl 632 3801 0 3761 6 1 5 5 0 8 1 srpgc 64 54 0 54 8 7 1 1 0 8 1 sosppl 128 29 0 29 7 7 0 1 0 8 0 sockpl 384 2749 0 2730 32 27 5 14 0 8 2 mcl64k 65536 14 0 0 2 0 2 2 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 6 0 0 1 0 1 1 0 8 0 mcl8k 8192 14 0 0 2 0 2 2 0 8 0 mcl4k 4096 14 0 0 2 0 2 2 0 8 0 mcl2k2 2112 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 152 0 0 18 1 17 18 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 403 0 0 20 0 20 20 0 8 0 bufpl 256 8017 0 1302 420 0 420 420 0 8 0 anonpl 16 164958 0 155771 89 32 57 64 0 124 8 amapchunkpl 152 11432 0 11328 13 7 6 10 0 158 0 amappl16 192 5839 0 5198 83 40 43 45 0 8 8 amappl15 184 188 0 188 4 4 0 1 0 8 0 amappl14 176 198 0 195 1 0 1 1 0 8 0 amappl13 168 35 0 34 1 0 1 1 0 8 0 amappl12 160 242 0 240 1 0 1 1 0 8 0 amappl11 152 270 0 259 1 0 1 1 0 8 0 amappl10 144 108 0 107 1 0 1 1 0 8 0 amappl9 136 1069 0 1063 1 0 1 1 0 8 0 amappl8 128 542 0 510 3 1 2 2 0 8 0 amappl7 120 222 0 214 1 0 1 1 0 8 0 amappl6 112 263 0 254 1 0 1 1 0 8 0 amappl5 104 537 0 524 1 0 1 1 0 8 0 amappl4 96 1365 0 1338 1 0 1 1 0 8 0 amappl3 88 307 0 301 1 0 1 1 0 8 0 amappl2 80 7107 0 7049 3 1 2 3 0 8 0 amappl1 72 43612 0 43192 24 14 10 20 0 8 0 amappl 80 4447 0 4412 4 2 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 64 129 0 0 3 0 3 3 0 8 0 uaddrrnd 24 1248 0 1233 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1248 0 1233 1 0 1 1 0 8 0 vmmpekpl 168 17015 0 16987 2 0 2 2 0 8 0 vmmpepl 168 175911 0 174192 168 62 106 115 0 357 24 vmsppl 368 1247 0 1233 2 0 2 2 0 8 0 pdppl 4096 2503 0 2466 7 1 6 6 0 8 1 pvpl 32 474499 0 462197 210 68 142 158 0 265 20 pmappl 232 1247 0 1233 8 6 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 615 0 29 17 0 17 17 0 8 0