panic: vput: v_writecount != 0
Stopped at db_enter+0x18: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
206645 83578 0 0x14000 0x200 0 reaper
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:207
vput(fffffd80641ced08) at vput+0x187 sys/kern/vfs_subr.c:759
vn_closefile(fffffd80644bd440,ffff800020b28018) at vn_closefile+0x15b sys/kern/vfs_vnops.c:583
fdrop(fffffd80644bd440,ffff800020b28018) at fdrop+0xc9 sys/kern/kern_descrip.c:1269
closef(fffffd80644bd440,ffff800020b28018) at closef+0x11d sys/kern/kern_descrip.c:1253
fdfree(ffff800020b28018) at fdfree+0xf8 sys/kern/kern_descrip.c:1185
exit1(ffff800020b28018,0,1) at exit1+0x32f sys/kern/kern_exit.c:196
sys_exit(ffff800020b28018,ffff800020b6fdf0,ffff800020b6fe60) at sys_exit+0x17 sys/kern/kern_exit.c:94
syscall(ffff800020b6fed0) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800020b6fed0) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,1,0,1,0,7f7fffff1704) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff16d0, 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
vput: v_writecount != 0
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
vput(fffffd80641ced08) at vput+0x187 sys/kern/vfs_subr.c:759
vn_closefile(fffffd80644bd440,ffff800020b28018) at vn_closefile+0x15b sys/kern/vfs_vnops.c:583
fdrop(fffffd80644bd440,ffff800020b28018) at fdrop+0xc9 sys/kern/kern_descrip.c:1269
closef(fffffd80644bd440,ffff800020b28018) at closef+0x11d sys/kern/kern_descrip.c:1253
fdfree(ffff800020b28018) at fdfree+0xf8 sys/kern/kern_descrip.c:1185
exit1(ffff800020b28018,0,1) at exit1+0x32f sys/kern/kern_exit.c:196
sys_exit(ffff800020b28018,ffff800020b6fdf0,ffff800020b6fe60) at sys_exit+0x17 sys/kern/kern_exit.c:94
syscall(ffff800020b6fed0) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800020b6fed0) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,1,0,1,0,7f7fffff1704) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff16d0, count: -11
ddb{1}> show registers
rdi 0
rsi 0x1
rbp 0xffff800020b6fae0
rbx 0xffff800020b6fb90
rdx 0xffff800020b28018
rcx 0
rax 0
r8 0xffffffff81c83d13 kprintf+0x173
r9 0x1
r10 0x25
r11 0x3880cdc0c63273c7
r12 0x3000000008
r13 0xffff800020b6faf0
r14 0x100
r15 0x1
rip 0xffffffff81a69fa8 db_enter+0x18
cs 0x8
rflags 0x246
rsp 0xffff800020b6fad0
ss 0x10
db_enter+0x18: addq $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor.0) pid=31079 stat=onproc
flags process=1008<EXITING,SINGLEEXIT> proc=2000<WEXIT>
pri=32, usrpri=86, nice=20
forw=0xffffffffffffffff, list=0xffff800020b293d8,0xffffffff82362638
process=0xffff800020b7d180 user=0xffff800020b6a000, vmspace=0xfffffd806e7e8458
estcpu=36, cpticks=15, pctcpu=0.0
user=0, sys=3, intr=0
ddb{1}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
50486 93459 0 0 3 0x14200 bored sosplice
72829 469981 78970 0 3 0x2 biowait syz-executor.1
94888 296548 78970 0 3 0x82 nanosleep syz-executor.0
78970 120712 1159 0 3 0x82 thrsleep syz-fuzzer
78970 234453 1159 0 3 0x4000082 nanosleep syz-fuzzer
78970 237648 1159 0 3 0x4000082 thrsleep syz-fuzzer
78970 473012 1159 0 3 0x4000082 thrsleep syz-fuzzer
78970 48288 1159 0 3 0x4000082 kqread syz-fuzzer
78970 521416 1159 0 3 0x4000082 thrsleep syz-fuzzer
78970 476790 1159 0 3 0x4000082 thrsleep syz-fuzzer
78970 46748 1159 0 3 0x4000082 thrsleep syz-fuzzer
78970 111599 1159 0 3 0x4000082 thrsleep syz-fuzzer
78970 488440 1159 0 3 0x4000082 thrsleep syz-fuzzer
1159 200664 7175 0 3 0x10008a pause ksh
7175 267814 18680 0 3 0x92 select sshd
8221 320729 1 0 3 0x100083 ttyopn getty
18680 206254 1 0 3 0x80 select sshd
74502 267497 80199 74 3 0x100092 bpf pflogd
80199 406665 1 0 3 0x80 netio pflogd
97253 45784 42686 73 3 0x100090 kqread syslogd
42686 249323 1 0 3 0x100082 netio syslogd
20497 243254 1 77 3 0x100090 poll dhclient
34608 160809 1 0 3 0x80 poll dhclient
51383 94040 0 0 3 0x14200 pgzero zerothread
80948 89843 0 0 3 0x14200 aiodoned aiodoned
72309 406125 0 0 3 0x14200 syncer update
37162 54516 0 0 3 0x14200 cleaner cleaner
83578 206645 0 0 7 0x14200 reaper
19941 73073 0 0 3 0x14200 pgdaemon pagedaemon
73489 460552 0 0 3 0x14200 bored crynlk
59460 104553 0 0 3 0x14200 bored crypto
41931 238109 0 0 3 0x40014200 acpi0 acpi0
62165 142693 0 0 3 0x40014200 idle1
63842 71933 0 0 3 0x14200 bored softnet
22907 218294 0 0 3 0x14200 bored systqmp
70239 62364 0 0 3 0x14200 bored systq
39257 516279 0 0 3 0x40014200 bored softclock
90109 207130 0 0 3 0x40014200 idle0
35787 206953 0 0 3 0x14200 bored smr
1 367076 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{1}> show all locks
Process 72829 (syz-executor.1) thread 0xffff800020b28508 (469981)
exclusive rrwlock inode r = 0 (0xfffffd8065fea4e8)
#0 witness_lock+0x52e sys/kern/subr_witness.c:1163
#1 rw_enter+0x46d sys/kern/kern_rwlock.c:306
#2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435
#3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602
#4 vn_lock+0x6e sys/kern/vfs_vnops.c:556
#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 ufs_lookup+0x1575 sys/ufs/ufs/ufs_lookup.c:487
#9 VOP_LOOKUP+0x5b sys/kern/vfs_vops.c:90
#10 vfs_lookup+0x7a5 sys/kern/vfs_lookup.c:567
#11 namei+0x61c sys/kern/vfs_lookup.c:248
#12 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1768
#13 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#13 syscall+0x552 sys/arch/amd64/amd64/trap.c:555
#14 Xsyscall+0x128
exclusive rrwlock inode r = 0 (0xfffffd806b125f78)
#0 witness_lock+0x52e sys/kern/subr_witness.c:1163
#1 rw_enter+0x46d sys/kern/kern_rwlock.c:306
#2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435
#3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602
#4 vn_lock+0x6e sys/kern/vfs_vnops.c:556
#5 vfs_lookup+0xec sys/kern/vfs_lookup.c:418
#6 namei+0x61c sys/kern/vfs_lookup.c:248
#7 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1768
#8 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
#8 syscall+0x552 sys/arch/amd64/amd64/trap.c:555
#9 Xsyscall+0x128
ddb{1}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim
devbuf 9562 6626K 7260K 78643K 14267 0 0
pcb 13 8K 8K 78643K 109 0 0
rtable 113 4K 4K 78643K 396 0 0
ifaddr 68 14K 15K 78643K 151 0 0
counters 39 33K 33K 78643K 39 0 0
ioctlops 0 0K 4K 78643K 1521 0 0
iov 0 0K 24K 78643K 133 0 0
mount 1 1K 1K 78643K 1 0 0
vnodes 1204 76K 77K 78643K 2312 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 20 0 0
VM map 2 1K 1K 78643K 2 0 0
sem 12 1K 1K 78643K 111 0 0
dirhash 12 2K 2K 78643K 12 0 0
ACPI 1808 196K 290K 78643K 12765 0 0
file desc 5 13K 25K 78643K 1134 0 0
sigio 0 0K 0K 78643K 10 0 0
proc 54 51K 71K 78643K 503 0 0
subproc 32 2K 2K 78643K 39 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 98 0 0
in_multi 33 2K 2K 78643K 45 0 0
ether_multi 1 0K 0K 78643K 3 0 0
mrt 0 0K 0K 78643K 17 0 0
ISOFS mount 1 32K 32K 78643K 1 0 0
MSDOSFS mount 1 16K 16K 78643K 1 0 0
ttys 60 265K 265K 78643K 60 0 0
exec 0 0K 1K 78643K 325 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 100 21K 30K 78643K 4544 0 0
UVM aobj 49 2K 2K 78643K 59 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 80 0 0
NDP 15 0K 0K 78643K 40 0 0
temp 193 2748K 2872K 78643K 6848 0 0
kqueue 0 0K 0K 78643K 6 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 7 0 0 1 0 1 1 0 8 0
plcache 128 20 0 0 1 0 1 1 0 8 0
rtpcb 80 65 0 63 1 0 1 1 0 8 0
rtentry 112 53 0 8 2 0 2 2 0 8 0
unpcb 120 346 0 334 1 0 1 1 0 8 0
syncache 264 4 0 4 1 1 0 1 0 8 0
tcpqe 32 8559 0 8559 2 2 0 1 0 8 0
tcpcb 544 160 0 156 1 0 1 1 0 8 0
inpcb 280 493 0 485 1 0 1 1 0 8 0
rttmr 72 11 0 11 1 0 1 1 0 8 1
nd6 48 6 0 0 1 0 1 1 0 8 0
pkpcb 40 4 0 4 2 1 1 1 0 8 1
swfcl 56 3 0 0 1 0 1 1 0 8 0
ppxss 1128 17 0 17 4 3 1 1 0 8 1
pffrag 232 2 0 2 1 1 0 1 0 482 0
pffrnode 88 2 0 2 1 1 0 1 0 8 0
pffrent 40 6 0 6 1 1 0 1 0 8 0
pfosfp 40 846 0 423 5 0 5 5 0 8 0
pfosfpen 112 1428 0 714 21 0 21 21 0 8 0
pfstitem 24 21 0 11 1 0 1 1 0 8 0
pfstkey 112 21 0 11 1 0 1 1 0 8 0
pfstate 328 21 0 11 1 0 1 1 0 8 0
pfrule 1360 21 0 16 2 1 1 2 0 8 0
art_heap8 4096 1 0 0 1 0 1 1 0 8 0
art_heap4 256 188 0 0 12 0 12 12 0 8 0
art_table 32 189 0 0 2 0 2 2 0 8 0
art_node 16 52 0 11 1 0 1 1 0 8 0
sysvmsgpl 40 4 0 4 2 2 0 1 0 8 0
semupl 112 1 0 1 1 1 0 1 0 8 0
semapl 112 109 0 99 1 0 1 1 0 8 0
shmpl 112 57 0 10 2 0 2 2 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino1pl 128 3127 0 1713 47 0 47 47 0 8 0
ffsino 272 3127 0 1713 96 0 96 96 0 8 0
nchpl 144 4890 0 3253 62 0 62 62 0 8 0
uvmvnodes 72 3998 0 0 73 0 73 73 0 8 0
vnodes 200 3998 0 0 211 0 211 211 0 8 0
namei 1024 14676 0 14676 2 1 1 1 0 8 1
percpumem 16 30 0 0 1 0 1 1 0 8 0
scsiplug 64 2 0 2 1 1 0 1 0 8 0
scxspl 192 14834 0 14833 15 14 1 6 0 8 0
plimitpl 152 101 0 93 1 0 1 1 0 8 0
sigapl 432 1334 0 1319 3 1 2 3 0 8 0
futexpl 56 13168 0 13168 1 0 1 1 0 8 1
knotepl 112 181 0 162 1 0 1 1 0 8 0
kqueuepl 104 206 0 204 1 0 1 1 0 8 0
pipepl 112 788 0 769 3 2 1 2 0 8 0
fdescpl 488 1335 0 1319 3 0 3 3 0 8 0
filepl 152 7344 0 7244 9 4 5 7 0 8 0
lockfpl 104 385 0 385 2 1 1 1 0 8 1
lockfspl 48 144 0 144 2 1 1 1 0 8 1
sessionpl 112 18 0 7 1 0 1 1 0 8 0
pgrppl 48 41 0 30 1 0 1 1 0 8 0
ucredpl 96 1161 0 1152 1 0 1 1 0 8 0
zombiepl 144 1320 0 1319 2 1 1 1 0 8 0
processpl 896 1351 0 1319 4 0 4 4 0 8 0
procpl 632 3753 0 3711 9 4 5 5 0 8 1
srpgc 64 3 0 3 2 1 1 1 0 8 1
sosppl 128 9 0 9 2 1 1 1 0 8 1
sockpl 384 917 0 896 5 2 3 4 0 8 0
mcl64k 65536 12 0 0 2 0 2 2 0 8 0
mcl16k 16384 3 0 0 1 0 1 1 0 8 0
mcl12k 12288 4 0 0 1 0 1 1 0 8 0
mcl9k 9216 6 0 0 1 0 1 1 0 8 0
mcl8k 8192 3 0 0 1 0 1 1 0 8 0
mcl4k 4096 10 0 0 2 0 2 2 0 8 0
mcl2k2 2112 3 0 0 1 0 1 1 0 8 0
mcl2k 2048 194 0 0 23 1 22 23 0 8 0
mtagpl 80 29 0 0 1 0 1 1 0 8 0
mbufpl 256 234 0 0 12 0 12 12 0 8 0
bufpl 256 8208 0 1179 440 0 440 440 0 8 0
anonpl 16 122999 0 111037 87 30 57 63 0 125 8
amapchunkpl 152 7491 0 7381 25 15 10 10 0 158 5
amappl16 192 6065 0 5407 51 16 35 42 0 8 1
amappl15 184 3 0 2 1 0 1 1 0 8 0
amappl14 176 53 0 47 1 0 1 1 0 8 0
amappl13 168 577 0 576 3 2 1 1 0 8 0
amappl12 160 23 0 18 1 0 1 1 0 8 0
amappl11 152 58 0 43 1 0 1 1 0 8 0
amappl10 144 605 0 599 1 0 1 1 0 8 0
amappl9 136 601 0 598 1 0 1 1 0 8 0
amappl8 128 142 0 126 1 0 1 1 0 8 0
amappl7 120 566 0 560 1 0 1 1 0 8 0
amappl6 112 61 0 53 1 0 1 1 0 8 0
amappl5 104 143 0 128 1 0 1 1 0 8 0
amappl4 96 1601 0 1574 2 1 1 2 0 8 0
amappl3 88 201 0 190 1 0 1 1 0 8 0
amappl2 80 9813 0 9741 3 1 2 3 0 8 0
amappl1 72 38363 0 37919 25 15 10 20 0 8 0
amappl 80 4004 0 3965 1 0 1 1 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
dma64 64 259 0 259 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 58 0 10 1 0 1 1 0 8 0
uaddrrnd 24 1335 0 1319 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 1335 0 1319 1 0 1 1 0 8 0
vmmpekpl 168 15403 0 15376 3 1 2 2 0 8 0
vmmpepl 168 167238 0 165445 131 46 85 99 0 357 2
vmsppl 368 1334 0 1319 2 0 2 2 0 8 0
pdppl 4096 2678 0 2638 8 2 6 6 0 8 0
pvpl 32 377876 0 362721 197 53 144 156 0 265 20
pmappl 232 1334 0 1319 2 1 1 2 0 8 0
extentpl 40 41 0 26 1 0 1 1 0 8 0
phpool 112 610 0 7 18 0 18 18 0 8 0