panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 64796 59981 32767 0x10 0 1K syz-executor.0 434758 64359 0 0x2 0x4000000 0 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(ffff800024f75488) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd80677bc700) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd80677bc700) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd80677bc700) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024f75710) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd80743f0a98,ffff800024f75870,ffff800024f758c0,ffff800024f757a0) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89b40,ffffff9c,7f7ffffea8d0,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024f75a40) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024f75a40) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffea8d0,88,0,7f7ffffea8f4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffea940, 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(ffff800024f75488) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd80677bc700) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd80677bc700) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd80677bc700) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024f75710) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd80743f0a98,ffff800024f75870,ffff800024f758c0,ffff800024f757a0) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89b40,ffffff9c,7f7ffffea8d0,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024f75a40) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024f75a40) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffea8d0,88,0,7f7ffffea8f4) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffea940, count: -11 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800024f753b0 rbx 0xffff800024f75460 rdx 0xffff800020a89b40 rcx 0 rax 0 r8 0xffffffff8100e32f kprintf+0x16f r9 0x1 r10 0x25 r11 0xa5153cc40ff2800a r12 0x3000000008 r13 0xffff800024f753c0 r14 0x100 r15 0x1 rip 0xffffffff8203e078 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800024f753a0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=64796 stat=onproc flags process=10 proc=0 pri=17, usrpri=52, nice=20 forw=0xffffffffffffffff, list=0xffff800020a898c8,0xffffffff82676ab8 process=0xffff800020a8a390 user=0xffff800024f70000, vmspace=0xfffffd807f00a5c0 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *59981 64796 32645 32767 7 0x10 syz-executor.0 32645 1686 64359 0 3 0x82 wait syz-executor.0 25575 458739 52958 32767 2 0x10 syz-executor.1 52958 114902 64359 0 3 0x82 wait syz-executor.1 71490 155453 0 0 3 0x14200 bored sosplice 64359 67315 53084 0 3 0x82 thrsleep syz-fuzzer 64359 280923 53084 0 3 0x4000082 nanosleep syz-fuzzer 64359 144631 53084 0 3 0x4000082 thrsleep syz-fuzzer 64359 114195 53084 0 3 0x4000082 thrsleep syz-fuzzer 64359 310735 53084 0 3 0x4000082 thrsleep syz-fuzzer 64359 366123 53084 0 3 0x4000082 thrsleep syz-fuzzer 64359 327293 53084 0 3 0x4000082 thrsleep syz-fuzzer 64359 434758 53084 0 7 0x4000002 syz-fuzzer 64359 246718 53084 0 3 0x4000082 thrsleep syz-fuzzer 64359 342870 53084 0 3 0x4000082 kqread syz-fuzzer 53084 461543 18026 0 3 0x10008a pause ksh 18026 45797 24296 0 3 0x92 select sshd 1711 420639 1 0 3 0x100083 ttyin getty 24296 444396 1 0 3 0x80 select sshd 59743 295498 1414 73 3 0x100090 kqread syslogd 1414 439481 1 0 3 0x100082 netio syslogd 74658 447317 1 77 3 0x100090 poll dhclient 83506 413956 1 0 3 0x80 poll dhclient 30740 55800 0 0 2 0x14200 zerothread 6965 372680 0 0 3 0x14200 aiodoned aiodoned 89547 257291 0 0 3 0x14200 syncer update 88346 80312 0 0 3 0x14200 cleaner cleaner 30003 493543 0 0 3 0x14200 reaper reaper 10418 71923 0 0 3 0x14200 pgdaemon pagedaemon 47836 121664 0 0 3 0x14200 bored crynlk 68472 170726 0 0 3 0x14200 bored crypto 890 323576 0 0 3 0x40014200 acpi0 acpi0 50920 356140 0 0 3 0x40014200 idle1 42296 333608 0 0 3 0x14200 bored softnet 83774 266055 0 0 3 0x14200 bored systqmp 86946 167946 0 0 3 0x14200 bored systq 39533 523131 0 0 3 0x40014200 bored softclock 42474 466910 0 0 3 0x40014200 idle0 76610 522659 0 0 3 0x14200 bored smr 1 2302 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 59981 (syz-executor.0) thread 0xffff800020a89b40 (64796) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82647ad0) #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 (0xfffffd806ffbe2c0) #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 (0xfffffd806fcc8b48) #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 25575 (syz-executor.1) thread 0xffff800020a88c70 (458739) exclusive rrwlock inode r = 0 (0xfffffd8063acb098) #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 9471 6323K 6323K 78643K 11603 0 0 pcb 13 12K 14K 78643K 17 0 0 rtable 105 3K 3K 78643K 8966 0 0 ifaddr 37 14K 14K 78643K 1327 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 412 0 0 iov 0 0K 32K 78643K 1176 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 76K 78643K 6833 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 112 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 1K 78643K 2331 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 33K 78643K 8064 0 0 sigio 0 0K 0K 78643K 146 0 0 proc 48 50K 83K 78643K 9911 0 0 subproc 34 2K 2K 78643K 3587 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 1K 78643K 776 0 0 in_multi 33 2K 2K 78643K 2498 0 0 ether_multi 1 0K 0K 78643K 15 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 3647 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 147 24K 34K 78643K 30334 0 0 UVM aobj 130 4K 4K 78643K 133 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 488 0 0 NDP 9 0K 0K 78643K 636 0 0 temp 121 3558K 3639K 78643K 44156 0 0 kqueue 0 0K 0K 78643K 179 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 64 440 0 434 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 1242 0 1240 1 0 1 1 0 8 0 rtentry 112 2151 0 2107 2 0 2 2 0 8 0 unpcb 120 5151 0 5133 12 11 1 2 0 8 0 syncache 264 59 0 59 18 18 0 1 0 8 0 tcpqe 32 10 0 10 8 8 0 1 0 8 0 tcpcb 544 4837 0 4833 110 109 1 14 0 8 0 ipq 40 109 0 109 27 27 0 1 0 8 0 ipqe 40 3825 0 3825 27 27 0 1 0 8 0 inpcb 280 11660 0 11651 85 83 2 13 0 8 1 ip6q 72 3 0 3 2 2 0 1 0 8 0 ip6af 40 9 0 9 2 2 0 1 0 8 0 nd6 48 422 0 418 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 9486 0 9271 14 0 14 14 0 8 0 art_table 32 9487 0 9271 2 0 2 2 0 8 0 art_node 16 2150 0 2110 1 0 1 1 0 8 0 sysvmsgpl 40 79 0 64 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 2329 0 2319 1 0 1 1 0 8 0 shmpl 112 131 0 3 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 10004 0 8576 47 0 47 47 0 8 0 ffsino 272 10004 0 8576 96 0 96 96 0 8 0 nchpl 144 19709 0 18094 60 0 60 60 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 106722 0 106721 1 0 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 57712 0 57712 68 65 3 7 0 8 3 plimitpl 152 1425 0 1416 1 0 1 1 0 8 0 sigapl 432 7608 0 7594 16 13 3 3 0 8 1 futexpl 56 141555 0 141555 1 0 1 1 0 8 1 knotepl 112 6394 0 6375 12 11 1 3 0 8 0 kqueuepl 104 5216 0 5214 25 24 1 4 0 8 0 pipepl 112 6064 0 6045 18 17 1 2 0 8 0 fdescpl 488 7609 0 7594 3 0 3 3 0 8 0 filepl 152 78037 0 77939 101 96 5 14 0 8 1 lockfpl 104 1794 0 1793 1 0 1 1 0 8 0 lockfspl 48 602 0 601 1 0 1 1 0 8 0 sessionpl 112 226 0 216 1 0 1 1 0 8 0 pgrppl 48 260 0 250 1 0 1 1 0 8 0 ucredpl 96 26002 0 25993 1 0 1 1 0 8 0 zombiepl 144 7594 0 7594 1 0 1 1 0 8 1 processpl 896 7625 0 7594 4 0 4 4 0 8 0 procpl 632 20194 0 20154 11 6 5 5 0 8 1 srpgc 64 418 0 418 12 11 1 1 0 8 1 sosppl 128 178 0 178 31 31 0 1 0 8 0 sockpl 384 18164 0 18137 136 131 5 22 0 8 0 mcl64k 65536 41 0 0 3 0 3 3 0 8 0 mcl16k 16384 18 0 0 3 0 3 3 0 8 1 mcl12k 12288 33 0 0 2 0 2 2 0 8 0 mcl9k 9216 40 0 0 3 1 2 2 0 8 0 mcl8k 8192 25 0 0 4 1 3 3 0 8 0 mcl4k 4096 25 0 0 3 0 3 3 0 8 0 mcl2k2 2112 10 0 0 1 0 1 1 0 8 0 mcl2k 2048 158 0 0 18 0 18 18 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 823 0 0 21 0 21 21 0 8 0 bufpl 256 29321 0 22277 441 0 441 441 0 8 0 anonpl 16 1016584 0 1006982 176 115 61 79 0 124 4 amapchunkpl 152 77261 0 77157 124 111 13 19 0 158 6 amappl16 192 35043 0 34373 269 223 46 57 0 8 8 amappl15 184 498 0 495 1 0 1 1 0 8 0 amappl14 176 2348 0 2347 1 0 1 1 0 8 0 amappl13 168 873 0 871 16 15 1 1 0 8 0 amappl12 160 806 0 797 2 1 1 1 0 8 0 amappl11 152 1382 0 1370 1 0 1 1 0 8 0 amappl10 144 753 0 749 1 0 1 1 0 8 0 amappl9 136 4123 0 4115 1 0 1 1 0 8 0 amappl8 128 3132 0 3055 5 2 3 3 0 8 0 amappl7 120 1557 0 1546 1 0 1 1 0 8 0 amappl6 112 1012 0 991 1 0 1 1 0 8 0 amappl5 104 2426 0 2414 1 0 1 1 0 8 0 amappl4 96 7612 0 7577 2 1 1 2 0 8 0 amappl3 88 1575 0 1570 1 0 1 1 0 8 0 amappl2 80 44424 0 44364 3 1 2 3 0 8 0 amappl1 72 224081 0 223673 24 14 10 20 0 8 0 amappl 80 23833 0 23798 3 1 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 64 132 0 3 3 0 3 3 0 8 0 uaddrrnd 24 7609 0 7594 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 7609 0 7594 1 0 1 1 0 8 0 vmmpekpl 168 72796 0 72766 2 0 2 2 0 8 0 vmmpepl 168 1066937 0 1065122 294 175 119 122 0 357 26 vmsppl 368 7608 0 7594 2 0 2 2 0 8 0 pdppl 4096 15225 0 15188 6 0 6 6 0 8 0 pvpl 32 2751427 0 2738691 439 286 153 185 0 265 21 pmappl 232 7608 0 7594 28 26 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 728 0 112 18 0 18 18 0 8 0