panic: fifo_badop called Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 82181 12324 32767 0x10 0 0K syz-executor.0 314530 61798 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(ffff800022d4ed98) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8063c8e500) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8063c8e500) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8063c8e500) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800022d4f020) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8063d490f0,ffff800022d4f180,ffff800022d4f1d0,ffff800022d4f0b0) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89b40,ffffff9c,7f7ffffe3d00,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800022d4f350) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800022d4f350) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffe3d00,88,0,7f7ffffe3d24) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe3d70, 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(ffff800022d4ed98) at fifo_badop+0x14 sys/miscfs/fifofs/fifo_vnops.c:491 VOP_STRATEGY(fffffd8063c8e500) at VOP_STRATEGY+0x99 sys/kern/vfs_vops.c:727 bwrite(fffffd8063c8e500) at bwrite+0x1b9 sys/kern/vfs_bio.c:738 VOP_BWRITE(fffffd8063c8e500) at VOP_BWRITE+0x4a sys/kern/vfs_vops.c:739 ufs_mkdir(ffff800022d4f020) at ufs_mkdir+0x6b7 sys/ufs/ufs/ufs_vnops.c:1250 VOP_MKDIR(fffffd8063d490f0,ffff800022d4f180,ffff800022d4f1d0,ffff800022d4f0b0) at VOP_MKDIR+0xc6 sys/kern/vfs_vops.c:450 domkdirat(ffff800020a89b40,ffffff9c,7f7ffffe3d00,1ff) at domkdirat+0x121 sys/kern/vfs_syscalls.c:2983 syscall(ffff800022d4f350) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800022d4f350) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,88,7f7ffffe3d00,88,0,7f7ffffe3d24) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe3d70, count: -11 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800022d4ecc0 rbx 0xffff800022d4ed70 rdx 0xffff800020a89b40 rcx 0 rax 0 r8 0xffffffff815b76df kprintf+0x16f r9 0x1 r10 0x25 r11 0xea1d44c8ead93fce r12 0x3000000008 r13 0xffff800022d4ecd0 r14 0x100 r15 0x1 rip 0xffffffff814bc358 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800022d4ecb0 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=82181 stat=onproc flags process=10 proc=0 pri=17, usrpri=77, nice=20 forw=0xffffffffffffffff, list=0xffff800020a88ee8,0xffffffff82675208 process=0xffff800020a8aa90 user=0xffff800022d4a000, vmspace=0xfffffd807f00a5c0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND *12324 82181 25301 32767 7 0x10 syz-executor.0 25301 22343 61798 0 3 0x82 wait syz-executor.0 1147 73905 36750 32767 2 0x10 syz-executor.1 36750 311622 61798 0 3 0x82 wait syz-executor.1 38645 211700 0 0 3 0x14200 bored sosplice 61798 454560 47906 0 3 0x82 thrsleep syz-fuzzer 61798 195397 47906 0 3 0x4000082 nanosleep syz-fuzzer 61798 434620 47906 0 3 0x4000082 thrsleep syz-fuzzer 61798 314530 47906 0 7 0x4000002 syz-fuzzer 61798 319996 47906 0 3 0x4000082 thrsleep syz-fuzzer 61798 65732 47906 0 3 0x4000082 thrsleep syz-fuzzer 61798 461810 47906 0 3 0x4000082 thrsleep syz-fuzzer 61798 171140 47906 0 3 0x4000082 thrsleep syz-fuzzer 61798 519123 47906 0 3 0x4000082 thrsleep syz-fuzzer 61798 513382 47906 0 2 0x4000002 syz-fuzzer 47906 480839 23159 0 3 0x10008a pause ksh 23159 91989 41064 0 3 0x92 select sshd 67497 501046 1 0 3 0x100083 ttyin getty 41064 74414 1 0 3 0x80 select sshd 40576 114860 54777 73 3 0x100090 kqread syslogd 54777 278133 1 0 3 0x100082 netio syslogd 27177 267334 1 77 3 0x100090 poll dhclient 81539 36614 1 0 3 0x80 poll dhclient 86887 326056 0 0 2 0x14200 zerothread 36952 46772 0 0 3 0x14200 aiodoned aiodoned 46307 93076 0 0 3 0x14200 syncer update 21536 509214 0 0 3 0x14200 cleaner cleaner 35193 434699 0 0 3 0x14200 reaper reaper 77560 313460 0 0 3 0x14200 pgdaemon pagedaemon 63068 20165 0 0 3 0x14200 bored crynlk 61101 423278 0 0 3 0x14200 bored crypto 20448 286292 0 0 3 0x40014200 acpi0 acpi0 26864 286460 0 0 3 0x40014200 idle1 35788 430232 0 0 3 0x14200 bored softnet 4596 408221 0 0 3 0x14200 bored systqmp 72888 391967 0 0 3 0x14200 bored systq 48717 7079 0 0 3 0x40014200 bored softclock 91299 245165 0 0 3 0x40014200 idle0 6463 119271 0 0 3 0x14200 bored smr 1 304734 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 12324 (syz-executor.0) thread 0xffff800020a89b40 (82181) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82646880) #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 (0xfffffd80654b4a38) #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 (0xfffffd80654b4e78) #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 1147 (syz-executor.1) thread 0xffff800020a89650 (73905) exclusive rrwlock inode r = 0 (0xfffffd80654b44e8) #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 9471 6323K 6323K 78643K 11233 0 0 pcb 13 12K 14K 78643K 17 0 0 rtable 105 3K 3K 78643K 12742 0 0 ifaddr 36 14K 15K 78643K 859 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 2K 78643K 259 0 0 iov 0 0K 48K 78643K 800 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1215 76K 76K 78643K 4218 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 60 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 12 0K 0K 78643K 44182 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 33K 78643K 9041 0 0 sigio 0 0K 0K 78643K 97 0 0 proc 48 50K 83K 78643K 6732 0 0 subproc 34 2K 2K 78643K 2329 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 499 0 0 in_multi 33 2K 2K 78643K 1700 0 0 ether_multi 1 0K 0K 78643K 25 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 2538 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 164 25K 35K 78643K 28359 0 0 UVM aobj 130 8K 8K 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 400 0 0 NDP 5 0K 0K 78643K 414 0 0 temp 121 3558K 3639K 78643K 37420 0 0 kqueue 0 0K 0K 78643K 79 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 64 286 0 280 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 21989 0 21987 1 0 1 1 0 8 0 rtentry 112 1405 0 1361 2 0 2 2 0 8 0 unpcb 120 46494 0 46484 7 6 1 2 0 8 0 syncache 264 44 0 44 19 19 0 1 0 8 0 sackhl 24 2 0 2 2 2 0 1 0 8 0 tcpqe 32 46 0 46 8 8 0 1 0 8 0 tcpcb 544 13570 0 13564 45 43 2 11 0 8 1 ipq 40 42 0 42 23 22 1 1 0 8 1 ipqe 40 908 0 908 23 22 1 1 0 8 1 inpcb 280 35587 0 35575 64 62 2 14 0 8 0 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 48 274 0 270 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 6336 0 6121 14 0 14 14 0 8 0 art_table 32 6337 0 6121 2 0 2 2 0 8 0 art_node 16 1404 0 1364 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 44178 0 44168 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 10279 0 8868 46 0 46 46 0 8 0 ffsino 272 10279 0 8868 96 1 95 95 0 8 0 nchpl 144 27625 0 26008 63 2 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 89550 0 89549 4 3 1 1 0 8 0 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 62284 0 62284 51 50 1 7 0 8 1 plimitpl 152 991 0 982 1 0 1 1 0 8 0 sigapl 432 8807 0 8793 6 4 2 3 0 8 0 futexpl 56 482959 0 482959 4 3 1 1 0 8 1 knotepl 112 4300 0 4281 7 6 1 2 0 8 0 kqueuepl 104 2196 0 2194 4 3 1 4 0 8 0 pipepl 112 3906 0 3887 11 10 1 2 0 8 0 fdescpl 488 8808 0 8793 3 0 3 3 0 8 1 filepl 152 158151 0 158053 61 56 5 14 0 8 1 lockfpl 104 2274 0 2273 1 0 1 1 0 8 0 lockfspl 48 731 0 730 1 0 1 1 0 8 0 sessionpl 112 152 0 142 1 0 1 1 0 8 0 pgrppl 48 196 0 186 1 0 1 1 0 8 0 ucredpl 96 9334 0 9325 1 0 1 1 0 8 0 zombiepl 144 8793 0 8793 4 3 1 1 0 8 1 processpl 896 8824 0 8793 4 0 4 4 0 8 0 procpl 632 21784 0 21744 32 27 5 5 0 8 1 srpgc 64 270 0 270 27 26 1 1 0 8 1 sosppl 128 156 0 156 31 31 0 1 0 8 0 sockpl 384 104186 0 104165 112 108 4 24 0 8 0 mcl64k 65536 32 0 0 3 0 3 3 0 8 0 mcl16k 16384 18 0 0 3 0 3 3 0 8 0 mcl12k 12288 45 0 0 2 0 2 2 0 8 0 mcl9k 9216 25 0 0 2 0 2 2 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 26 0 0 4 1 3 3 0 8 0 mcl2k2 2112 9 0 0 1 0 1 1 0 8 0 mcl2k 2048 185 0 0 18 6 12 18 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 947 0 0 31 0 31 31 0 8 0 bufpl 256 23500 0 16456 441 0 441 441 0 8 0 anonpl 16 1137104 0 1127447 212 156 56 65 0 124 1 amapchunkpl 152 66817 0 66700 136 125 11 19 0 158 5 amappl16 192 39857 0 39222 297 256 41 45 0 8 8 amappl15 184 1226 0 1226 3 3 0 1 0 8 0 amappl14 176 1417 0 1413 1 0 1 1 0 8 0 amappl13 168 275 0 273 13 12 1 1 0 8 0 amappl12 160 584 0 580 1 0 1 1 0 8 0 amappl11 152 860 0 848 1 0 1 1 0 8 0 amappl10 144 4267 0 4261 1 0 1 1 0 8 0 amappl9 136 2774 0 2766 1 0 1 1 0 8 0 amappl8 128 2220 0 2133 4 0 4 4 0 8 0 amappl7 120 4833 0 4825 1 0 1 1 0 8 0 amappl6 112 554 0 534 1 0 1 1 0 8 0 amappl5 104 1668 0 1656 1 0 1 1 0 8 0 amappl4 96 12141 0 12108 1 0 1 1 0 8 0 amappl3 88 1203 0 1197 1 0 1 1 0 8 0 amappl2 80 59813 0 59751 3 1 2 3 0 8 0 amappl1 72 234626 0 234207 31 21 10 20 0 8 0 amappl 80 24241 0 24200 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 64 132 0 3 3 0 3 3 0 8 0 uaddrrnd 24 8808 0 8793 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 8808 0 8793 1 0 1 1 0 8 0 vmmpekpl 168 70124 0 70093 2 0 2 2 0 8 0 vmmpepl 168 1170494 0 1168690 261 147 114 124 0 357 20 vmsppl 368 8807 0 8793 2 0 2 2 0 8 0 pdppl 4096 17623 0 17586 6 0 6 6 0 8 1 pvpl 32 2792044 0 2779211 450 307 143 164 0 265 10 pmappl 232 8807 0 8793 10 8 2 2 0 8 1 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 676 0 56 18 0 18 18 0 8 0