panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *325567 52403 32767 0x10 0 1K syz-executor.1 394988 72560 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(ffff800024f68e18) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8068a03c00) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8068a03c00) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8068a03c00) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024f690a0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd806774b900,ffff800024f69200,ffff800024f69250,ffff800024f69130) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020ab0780,ffffff9c,7f7fffff5f60,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024f693d0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024f693d0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7fffff5f60,88,0,7f7fffff5f84) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff5fd0, 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(ffff800024f68e18) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8068a03c00) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8068a03c00) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8068a03c00) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800024f690a0) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd806774b900,ffff800024f69200,ffff800024f69250,ffff800024f69130) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020ab0780,ffffff9c,7f7fffff5f60,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800024f693d0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800024f693d0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7fffff5f60,88,0,7f7fffff5f84) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff5fd0, count: -11 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800024f68d40 rbx 0xffff800024f68df0 rdx 0xffff800020ab0780 rcx 0 rax 0 r8 0xffffffff820e3b9f kprintf+0x16f r9 0x1 r10 0x25 r11 0xb485634aa232e831 r12 0x3000000008 r13 0xffff800024f68d50 r14 0x100 r15 0x1 rip 0xffffffff81634f28 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800024f68d30 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=325567 stat=onproc flags process=10 proc=0 pri=17, usrpri=71, nice=20 forw=0xffffffffffffffff, list=0xffff800020ab0c70,0xffffffff8262a918 process=0xffff800020a8bc10 user=0xffff800024f64000, vmspace=0xfffffd807f00bcf0 estcpu=36, cpticks=2, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *52403 325567 67524 32767 7 0x10 syz-executor.1 67524 373936 72560 0 3 0x82 wait syz-executor.1 89544 97920 18939 32767 2 0x10 syz-executor.0 18939 162479 72560 0 3 0x82 wait syz-executor.0 79325 507053 0 0 3 0x14200 bored sosplice 72560 154034 76322 0 3 0x82 thrsleep syz-fuzzer 72560 208998 76322 0 3 0x4000082 nanosleep syz-fuzzer 72560 209446 76322 0 3 0x4000082 thrsleep syz-fuzzer 72560 467269 76322 0 3 0x4000082 thrsleep syz-fuzzer 72560 74493 76322 0 3 0x4000082 thrsleep syz-fuzzer 72560 376495 76322 0 3 0x4000082 thrsleep syz-fuzzer 72560 261527 76322 0 3 0x4000082 thrsleep syz-fuzzer 72560 192277 76322 0 3 0x4000082 thrsleep syz-fuzzer 72560 196247 76322 0 2 0x4000002 syz-fuzzer 72560 394988 76322 0 7 0x4000002 syz-fuzzer 76322 280542 68354 0 3 0x10008a pause ksh 68354 138484 61549 0 3 0x92 select sshd 99975 274968 1 0 3 0x100083 ttyin getty 61549 351847 1 0 3 0x80 select sshd 79631 392046 27878 73 3 0x100090 kqread syslogd 27878 359906 1 0 3 0x100082 netio syslogd 93611 356756 1 77 3 0x100090 poll dhclient 5288 26956 1 0 3 0x80 poll dhclient 37607 185476 0 0 2 0x14200 zerothread 81980 267377 0 0 3 0x14200 aiodoned aiodoned 29720 190947 0 0 3 0x14200 syncer update 93286 342749 0 0 3 0x14200 cleaner cleaner 1390 108163 0 0 3 0x14200 reaper reaper 84205 507654 0 0 3 0x14200 pgdaemon pagedaemon 21927 269268 0 0 3 0x14200 bored crynlk 69347 356165 0 0 3 0x14200 bored crypto 14108 506540 0 0 3 0x40014200 acpi0 acpi0 18646 466180 0 0 3 0x40014200 idle1 10323 482171 0 0 3 0x14200 bored softnet 93176 165044 0 0 3 0x14200 bored systqmp 28012 453311 0 0 3 0x14200 bored systq 64288 152172 0 0 3 0x40014200 bored softclock 89487 318030 0 0 3 0x40014200 idle0 54612 259065 0 0 3 0x14200 bored smr 1 425289 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 52403 (syz-executor.1) thread 0xffff800020ab0780 (325567) 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 (0xfffffd8073c19700) #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 (0xfffffd8073c19d60) #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 89544 (syz-executor.0) thread 0xffff800020ab18c8 (97920) exclusive rrwlock inode r = 0 (0xfffffd8073c193d0) #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 9473 6323K 6323K 78643K 12311 0 0 pcb 13 10K 12K 78643K 15 0 0 rtable 109 3K 3K 78643K 14892 0 0 ifaddr 35 17K 21K 78643K 2193 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 699 0 0 iov 0 0K 44K 78643K 2374 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 76K 78643K 8523 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 187 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 1K 78643K 6621 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 33K 78643K 14281 0 0 sigio 0 0K 0K 78643K 243 0 0 proc 48 50K 83K 78643K 16556 0 0 subproc 34 2K 2K 78643K 5984 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 1482 0 0 in_multi 33 2K 2K 78643K 4251 0 0 ether_multi 1 0K 0K 78643K 38 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 126 556K 556K 78643K 126 0 0 exec 0 0K 1K 78643K 6127 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 166 25K 37K 78643K 52694 0 0 UVM aobj 130 5K 5K 78643K 134 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 829 0 0 NDP 9 0K 0K 78643K 1059 0 0 temp 121 3558K 3654K 78643K 73634 0 0 kqueue 0 0K 0K 78643K 193 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 64 726 0 720 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 2012 0 2010 1 0 1 1 0 8 0 rtentry 112 3568 0 3522 2 0 2 2 0 8 0 unpcb 120 12202 0 12180 19 17 2 2 0 8 1 syncache 264 99 0 99 40 40 0 1 0 8 0 tcpqe 32 23 0 23 14 14 0 1 0 8 0 tcpcb 544 12189 0 12185 113 112 1 15 0 8 0 ipq 40 176 0 176 47 47 0 1 0 8 0 ipqe 40 5630 0 5630 47 47 0 1 0 8 0 inpcb 280 31357 0 31346 95 93 2 10 0 8 0 ip6q 72 10 0 10 6 6 0 1 0 8 0 ip6af 40 425 0 425 6 6 0 1 0 8 0 nd6 48 705 0 701 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 15817 0 15572 16 0 16 16 0 8 0 art_table 32 15818 0 15572 6 3 3 3 0 8 1 art_node 16 3567 0 3525 1 0 1 1 0 8 0 sysvmsgpl 40 61 0 42 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 6617 0 6607 1 0 1 1 0 8 0 shmpl 112 132 0 4 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 14778 0 13339 47 0 47 47 0 8 0 ffsino 272 14778 0 13339 98 1 97 97 0 8 0 nchpl 144 31914 0 30282 61 0 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 155180 0 155179 1 0 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 105245 0 105245 100 97 3 4 0 8 3 plimitpl 152 2550 0 2541 1 0 1 1 0 8 0 sigapl 432 13402 0 13388 18 15 3 3 0 8 1 futexpl 56 281415 0 281415 1 0 1 1 0 8 1 knotepl 112 10581 0 10562 15 14 1 3 0 8 0 kqueuepl 104 6410 0 6408 30 29 1 4 0 8 0 pipepl 112 12756 0 12737 35 34 1 2 0 8 0 fdescpl 488 13403 0 13388 3 0 3 3 0 8 0 filepl 152 125093 0 124995 145 139 6 14 0 8 2 lockfpl 104 3337 0 3336 1 0 1 1 0 8 0 lockfspl 48 1128 0 1127 1 0 1 1 0 8 0 sessionpl 112 367 0 357 1 0 1 1 0 8 0 pgrppl 48 446 0 436 1 0 1 1 0 8 0 ucredpl 96 20170 0 20161 1 0 1 1 0 8 0 zombiepl 144 13388 0 13388 1 0 1 1 0 8 1 processpl 896 13419 0 13388 4 0 4 4 0 8 0 procpl 632 36880 0 36840 10 5 5 5 0 8 1 srpgc 64 700 0 700 29 28 1 1 0 8 1 sosppl 128 383 0 383 62 62 0 1 0 8 0 sockpl 384 45922 0 45891 148 142 6 15 0 8 1 mcl64k 65536 81 0 0 3 0 3 3 0 8 0 mcl16k 16384 41 0 0 6 3 3 3 0 8 0 mcl12k 12288 65 0 0 2 0 2 2 0 8 0 mcl9k 9216 50 0 0 2 0 2 2 0 8 0 mcl8k 8192 34 0 0 3 1 2 3 0 8 0 mcl4k 4096 29 0 0 4 1 3 3 0 8 0 mcl2k2 2112 11 0 0 1 0 1 1 0 8 0 mcl2k 2048 141 0 0 15 0 15 15 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 1282 0 0 22 1 21 21 0 8 0 bufpl 256 39926 0 32882 441 0 441 441 0 8 0 anonpl 16 1801663 0 1792423 243 186 57 66 0 124 0 amapchunkpl 152 133984 0 133865 223 213 10 19 0 158 3 amappl16 192 62133 0 61488 435 399 36 47 0 8 1 amappl15 184 1910 0 1910 32 32 0 1 0 8 0 amappl14 176 4497 0 4488 1 0 1 1 0 8 0 amappl13 168 1169 0 1169 33 33 0 1 0 8 0 amappl12 160 1315 0 1308 2 1 1 1 0 8 0 amappl11 152 2137 0 2126 1 0 1 1 0 8 0 amappl10 144 1281 0 1273 1 0 1 1 0 8 0 amappl9 136 6548 0 6542 1 0 1 1 0 8 0 amappl8 128 4936 0 4842 5 1 4 4 0 8 0 amappl7 120 2609 0 2601 1 0 1 1 0 8 0 amappl6 112 1269 0 1247 1 0 1 1 0 8 0 amappl5 104 3929 0 3919 1 0 1 1 0 8 0 amappl4 96 13596 0 13558 3 1 2 2 0 8 0 amappl3 88 3273 0 3267 1 0 1 1 0 8 0 amappl2 80 80235 0 80170 3 1 2 3 0 8 0 amappl1 72 386234 0 385815 24 14 10 20 0 8 0 amappl 80 42714 0 42678 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 64 133 0 4 3 0 3 3 0 8 0 uaddrrnd 24 13403 0 13388 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 13403 0 13388 1 0 1 1 0 8 0 vmmpekpl 168 130276 0 130246 2 0 2 2 0 8 0 vmmpepl 168 1866280 0 1864449 428 312 116 124 0 357 23 vmsppl 368 13402 0 13388 2 0 2 2 0 8 0 pdppl 4096 26813 0 26776 6 0 6 6 0 8 0 pvpl 32 4775841 0 4763441 669 536 133 164 0 265 0 pmappl 232 13402 0 13388 45 43 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 736 0 121 18 0 18 18 0 8 0