panic: vrele: v_writecount != 0
Stopped at db_enter+0x25: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*398388 34674 0 0x1004 0 0K syz-executor
473061 92638 73 0x1100010 0x1 1 syslogd
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8331ff57) at panic+0x1e5 sys/kern/subr_prf.c:198
vrele(fffffd806d0943a0) at vrele+0x274
uvn_detach(fffffd806e3e0e68) at uvn_detach+0x1b7 sys/uvm/uvm_vnode.c:375
uvm_unmap_detach(ffff80003c4379d8,0) at uvm_unmap_detach+0x15e sys/uvm/uvm_map.c:1364
uvmspace_exec(ffff800035fe6fb0,1000,7f7fffffc000) at uvmspace_exec+0x3b7 sys/uvm/uvm_map.c:3393
sys_execve(ffff800035fe6fb0,ffff80003c438070,ffff80003c437fc0) at sys_execve+0xc31 sys/kern/kern_exec.c:453
syscall(ffff80003c438070) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c438070) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7255a3cbf710, count: 6
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
*cpu0: vrele: v_writecount != 0
ddb{0}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8331ff57) at panic+0x1e5 sys/kern/subr_prf.c:198
vrele(fffffd806d0943a0) at vrele+0x274
uvn_detach(fffffd806e3e0e68) at uvn_detach+0x1b7 sys/uvm/uvm_vnode.c:375
uvm_unmap_detach(ffff80003c4379d8,0) at uvm_unmap_detach+0x15e sys/uvm/uvm_map.c:1364
uvmspace_exec(ffff800035fe6fb0,1000,7f7fffffc000) at uvmspace_exec+0x3b7 sys/uvm/uvm_map.c:3393
sys_execve(ffff800035fe6fb0,ffff80003c438070,ffff80003c437fc0) at sys_execve+0xc31 sys/kern/kern_exec.c:453
syscall(ffff80003c438070) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c438070) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7255a3cbf710, count: -9
ddb{0}> show registers
rdi 0
rsi 0x1
rbp 0xffff80003c437820
rbx 0xffffffff8384ce07 cpu_info_full_primary+0x2e07
rdx 0
rcx 0xffff800035fe6fb0
rax 0xffffffff8384bff0 cpu_info_full_primary+0x1ff0
r8 0x101010101010101
r9 0x8080808080808080
r10 0x8549635570749ef3
r11 0xd878fc471b2ef65f
r12 0xffffffff8384cc08 cpu_info_full_primary+0x2c08
r13 0
r14 0
r15 0x1
rip 0xffffffff82d87095 db_enter+0x25
cs 0x8
rflags 0x246
rsp 0xffff80003c437810
ss 0x10
db_enter+0x25: addq $0x8,%rsp
ddb{0}> show proc
PROC (syz-executor) tid=398388 pid=34674 tcnt=1 stat=onproc
flags process=1004<INEXEC,SINGLEEXIT> proc=0
runpri=50, usrpri=86, slppri=24, nice=20
wchan=0x0, wmesg=, ps_single=0xffff800035fe6fb0 scnt=0 ecnt=0
forw=0xffffffffffffffff, list=0xffff800035fe67e8,0xffff800035fe7cb8
process=0xffff8000fffeb508 user=0xffff80003c433000, vmspace=0xfffffd806c200018
estcpu=36, cpticks=2, pctcpu=0.0, user=0, sys=2, intr=0
ddb{0}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
68316 227081 7516 0 2 0 syz-executor
68316 341177 7516 0 2 0x4000000 syz-executor
*34674 398388 7748 0 7 0x1004 syz-executor
57186 521897 47491 0 2 0 syz-executor
57186 13893 47491 0 3 0x4000080 fsleep syz-executor
88827 450591 5036 0 2 0 syz-executor
88827 483865 5036 0 3 0x4000080 fsleep syz-executor
88827 297061 5036 0 2 0x4000000 syz-executor
66706 445674 90018 0 2 0 syz-executor
66706 43206 90018 0 3 0x4000080 fsleep syz-executor
62097 150135 21831 0 2 0xc80 syz-executor
62097 231883 21831 0 3 0x4000080 pipewr syz-executor
62097 475693 21831 0 3 0x4000080 fsleep syz-executor
67167 316585 0 0 3 0x14280 nfsidl nfsio
58731 493640 0 0 3 0x14280 nfsidl nfsio
51094 379829 0 0 3 0x14280 nfsidl nfsio
23449 237337 0 0 3 0x14280 nfsidl nfsio
74713 456944 0 0 3 0x14280 nfsidl nfsio
41294 233337 0 0 3 0x14280 nfsidl nfsio
4860 314767 1 0 3 0x100083 ttyin getty
7516 90765 7748 0 2 0xc82 syz-executor
5036 520686 7748 0 2 0x2 syz-executor
94833 88256 7748 0 3 0x82 wait syz-executor
47491 19709 7748 0 2 0xc82 syz-executor
21831 40200 7748 0 2 0x2 syz-executor
90018 192004 7748 0 2 0xc82 syz-executor
86204 266808 7748 0 2 0x2 syz-executor
7748 505919 65983 0 3 0x82 kqread syz-executor
65983 145946 94612 0 3 0x10008a sigsusp ksh
94612 362241 52825 0 3 0x98 kqread sshd-session
52825 51210 73823 0 3 0x92 kqread sshd-session
73823 285255 1 0 3 0x88 kqread sshd
55186 242579 77357 74 3 0x1100092 bpf pflogd
77357 363888 1 0 3 0x80 sbwait pflogd
92638 473061 23836 73 7 0x1100011 syslogd
23836 200025 1 0 3 0x100082 sbwait syslogd
90167 271827 1 0 3 0x100080 kqread resolvd
84374 210035 97240 77 3 0x100092 kqread dhcpleased
34032 63258 97240 77 3 0x100092 kqread dhcpleased
97240 388555 1 0 3 0x80 kqread dhcpleased
17651 301473 0 0 3 0x14200 bored smr
27347 164189 0 0 2 0x14200 zerothread
35374 479520 0 0 3 0x14200 aiodoned aiodoned
493 83198 0 0 3 0x14200 syncer update
3348 166478 0 0 3 0x14200 cleaner cleaner
18149 318700 0 0 3 0x14200 reaper reaper
99217 48320 0 0 3 0x14200 pgdaemon pagedaemon
45349 520776 0 0 3 0x14200 bored viomb
51021 303847 0 0 3 0x40014200 acpi0 acpi0
22070 497180 0 0 3 0x40014200 idle1
26506 442904 0 0 3 0x14200 bored softnet1
22964 293027 0 0 3 0x14200 bored softnet0
92467 426937 0 0 3 0x14200 bored systqmp
80729 148956 0 0 3 0x14200 bored systq
59181 51100 0 0 3 0x14200 tmoslp softclockmp
95447 52160 0 0 3 0x40014200 tmoslp softclock
97784 445132 0 0 3 0x40014200 idle0
1 414004 0 0 3 0x82 wait init
0 0 -1 0 3 0x10010200 scheduler swapper
ddb{0}> show all locks
Process 34674 (syz-executor) thread 0xffff800035fe6fb0 (398388)
exclusive kernel_lock &kernel_lock r = 1 (0xffffffff83901248)
#0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1 syscall+0xaf4 mi_syscall sys/sys/syscall_mi.h:175 [inline]
#1 syscall+0xaf4 sys/arch/amd64/amd64/trap.c:765
#2 Xsyscall+0x128
ddb{0}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 10223 11031K 11424K 166960K 12374 0
pcb 17 13K 14K 166960K 178 0
rtable 212 10K 10K 166960K 447 0
pf 34 17K 67486K 166960K 141 0
ifaddr 39 7K 8K 166960K 87 0
ifgroup 51 2K 2K 166960K 135 0
sysctl 4 1K 9K 166960K 12 0
counters 66 36K 37K 166960K 166 0
ioctlops 0 0K 8K 166960K 1683 0
iov 0 0K 16K 166960K 42 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1412 89K 89K 166960K 2190 0
UFS quota 1 32K 32K 166960K 1 0
UFS mount 5 36K 36K 166960K 5 0
shm 2 1K 9K 166960K 15 0
VM map 2 1K 1K 166960K 2 0
sem 16 3K 3K 166960K 65 0
dirhash 12 2K 2K 166960K 24 0
ACPI 1692 195K 286K 166960K 12470 0
file desc 16 54K 240K 166960K 896 0
sigio 0 0K 0K 166960K 11 0
proc 72 115K 180K 166960K 655 0
subproc 63 3K 4K 166960K 81 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 16K 16K 166960K 1 0
ip_moptions 0 0K 0K 166960K 100 0
in_multi 90 6K 7K 166960K 146 0
ether_multi 1 0K 0K 166960K 12 0
mrt 2 0K 0K 166960K 12 0
ISOFS mount 1 32K 32K 166960K 1 0
MSDOSFS mount 1 16K 16K 166960K 1 0
ttys 247 1102K 1102K 166960K 247 0
exec 1 0K 1K 166960K 529 0
fusefs mount 1 32K 32K 166960K 1 0
tdb 3 0K 0K 166960K 3 0
VM swap 8 62K 64K 166960K 10 0
UVM amap 223 150K 177K 166960K 9462 0
UVM aobj 53 6K 6K 166960K 58 0
pinsyscall 42 84K 104K 166960K 2033 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 2 0K 0K 166960K 57 0
NDP 11 0K 1K 166960K 60 0
temp 53 8658K 8752K 166960K 30862 0
kqueue 13 20K 29K 166960K 147 0
SYN cache 2 16K 16K 166960K 2 0
ddb{0}> show all pools
Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
plcache 128 26 0 0 1 0 1 1 0 8 0
rtpcb 120 78 0 75 1 0 1 1 0 8 0
rtentry 176 133 0 47 6 0 6 6 0 8 0
unpcb 144 579 0 560 8 4 4 6 0 8 3
syncache 336 5 0 5 2 2 0 1 0 8 0
tcpqe 32 1 0 1 1 1 0 1 0 8 0
tcpcb 736 254 0 246 7 6 1 4 0 8 0
arp 136 21 0 7 1 0 1 1 0 8 0
inpcb 328 911 0 899 13 10 3 7 0 8 1
nd6 152 29 0 6 1 0 1 1 0 8 0
pkpcb 40 2 0 2 2 2 0 1 0 8 0
kcovpl 48 9 0 2 1 0 1 1 0 8 0
ppxss 1192 42 0 42 3 2 1 1 0 8 1
pppxif 1504 1 0 1 1 1 0 1 0 8 0
pfstscr 40 6 0 6 1 1 0 1 0 8 0
pffrag 232 75 0 66 1 0 1 1 0 482 0
pffrnode 88 9 0 1 1 0 1 1 0 8 0
pffrent 40 143 0 134 1 0 1 1 0 8 0
pfosfp 40 1429 0 1005 5 0 5 5 0 8 0
pfosfpen 112 1429 0 714 21 0 21 21 0 8 0
pfstitem 24 70 0 19 1 0 1 1 0 8 0
pfstkey 128 76 0 25 2 0 2 2 0 8 0
pfstate 384 72 0 22 6 0 6 6 0 8 0
pfrule 1344 29 0 22 2 1 1 2 0 8 0
art_heap8 4096 1 0 0 1 0 1 1 0 8 0
art_heap4 256 593 0 219 33 8 25 31 0 8 0
art_table 40 594 0 219 5 0 5 5 0 8 0
art_node 32 132 0 55 1 0 1 1 0 8 0
sysvmsgpl 40 6 0 2 1 0 1 1 0 8 0
semupl 112 4 0 4 2 2 0 1 0 8 0
semapl 112 59 0 45 1 0 1 1 0 8 0
shmpl 112 53 0 5 2 0 2 2 0 8 0
dirhash 1024 26 0 9 3 0 3 3 0 8 0
dino2pl 256 3067 0 1554 96 0 96 96 0 8 0
ffsino 296 3067 0 1554 118 0 118 118 0 8 0
nchpl 144 4277 0 2574 64 0 64 64 0 8 0
rtmask 32 8 0 8 2 2 0 1 0 8 0
vnodes 216 3592 0 0 200 0 200 200 0 8 0
namei 1024 15291 0 15290 2 1 1 1 0 8 0
percpumem 16 98 0 50 1 0 1 1 0 8 0
vcpupl 3968 2 0 0 1 0 1 1 0 8 0
vmpool 840 2 0 0 1 0 1 1 0 8 0
kstatmem 264 86 0 62 4 2 2 3 0 8 0
acpiwqpl 32 1 0 1 1 0 1 1 1 8 1
scsiplug 72 8 0 8 3 2 1 1 0 8 1
scxspl 216 21972 0 21972 11 9 2 8 1 8 2
plimitpl 152 538 0 522 1 0 1 1 0 8 0
sigapl 424 1197 0 1145 9 1 8 8 0 8 0
knotepl 120 568 0 0 17 0 17 17 0 8 0
kqueuepl 224 352 0 343 6 4 2 5 0 8 1
pipepl 344 232 0 204 9 6 3 9 0 8 0
fdescpl 528 1157 0 1127 3 0 3 3 0 8 0
filepl 160 7818 0 7607 19 6 13 16 0 8 0
lockfpl 104 535 0 533 2 1 1 2 0 8 0
lockfspl 48 211 0 209 1 0 1 1 0 8 0
sessionpl 144 27 0 18 1 0 1 1 0 8 0
pgrppl 48 143 0 126 1 0 1 1 0 8 0
ucredpl 104 1883 0 1870 1 0 1 1 0 8 0
zombiepl 144 1146 0 1145 1 0 1 1 0 8 0
processpl 1232 1197 0 1145 7 2 5 6 0 8 0
procpl 664 2444 0 2385 7 0 7 7 0 8 0
sosppl 176 6 0 6 2 1 1 1 0 8 1
sockpl 752 1598 0 1564 25 14 11 17 0 8 7
mcl64k 65536 4 0 0 1 0 1 1 0 8 0
mcl16k 16384 1 0 0 1 0 1 1 0 8 0
mcl8k 8192 4 0 0 1 0 1 1 0 8 0
mcl4k 4096 131 0 0 17 0 17 17 0 8 0
mcl2k2 2112 1 0 0 1 0 1 1 0 8 0
mcl2k 2048 36 0 0 5 0 5 5 0 8 0
mtagpl 96 5 0 0 1 0 1 1 0 8 0
mbufpl 256 205 0 0 13 0 13 13 0 8 0
bufpl 280 8087 0 1950 439 0 439 439 0 8 0
anonpl 32 11360 0 0 92 0 92 92 0 246 0
amapchunkpl 152 31476 0 31039 43 8 35 35 0 158 15
amappl16 200 3792 0 3760 36 21 15 27 0 8 6
amappl15 192 24 0 24 1 1 0 1 0 8 0
amappl14 184 6 0 6 1 1 0 1 0 8 0
amappl13 176 440 0 439 1 0 1 1 0 8 0
amappl12 168 1539 0 1499 3 0 3 3 0 8 0
amappl11 160 8 0 8 1 1 0 1 0 8 0
amappl10 152 125 0 109 1 0 1 1 0 8 0
amappl9 144 276 0 276 2 2 0 1 0 8 0
amappl8 136 26 0 23 1 0 1 1 0 8 0
amappl7 128 85 0 84 1 0 1 1 0 8 0
amappl6 120 292 0 279 1 0 1 1 0 8 0
amappl5 112 90 0 79 1 0 1 1 0 8 0
amappl4 104 431 0 399 1 0 1 1 0 8 0
amappl3 96 5447 0 5363 4 1 3 3 0 8 0
amappl2 88 1299 0 1222 2 0 2 2 0 8 0
amappl1 80 12728 0 12155 14 0 14 14 0 8 0
amappl 88 8573 0 8426 5 0 5 5 0 92 0
uvmvnodes 80 130 0 0 3 0 3 3 0 8 0
dma65536 65536 2 0 2 1 1 0 1 0 8 0
dma16384 16384 1 0 1 1 0 1 1 0 8 1
dma4096 4096 1 0 1 1 1 0 1 0 8 0
dma1024 1024 1 0 0 1 0 1 1 0 8 0
dma256 256 6 0 6 1 1 0 1 0 8 0
dma128 128 254 0 254 2 2 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 18 0 17 1 0 1 1 0 8 0
aobjpl 72 57 0 5 1 0 1 1 0 8 0
uaddrrnd 24 1158 0 1128 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 1158 0 1128 1 0 1 1 0 8 0
vmmpekpl 168 11315 0 11259 3 0 3 3 0 8 0
vmmpepl 168 79874 0 78031 107 9 98 107 0 357 2
vmsppl 488 1157 0 1128 5 0 5 5 0 8 0
rwobjpl 80 23395 0 22321 34 5 29 32 0 8 0
pdppl 4096 2327 0 2258 107 34 73 85 0 8 4
pvpl 32 17572 0 0 143 1 142 143 0 265 0
pmappl 256 1159 0 1128 3 0 3 3 0 8 0
extentpl 40 45 0 27 1 0 1 1 0 8 0
phpool 112 297 0 54 8 0 8 8 0 8 0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438
panic(ffffffff8331ff57) at panic+0x1e5 sys/kern/subr_prf.c:198
vrele(fffffd806d0943a0) at vrele+0x274
uvn_detach(fffffd806e3e0e68) at uvn_detach+0x1b7 sys/uvm/uvm_vnode.c:375
uvm_unmap_detach(ffff80003c4379d8,0) at uvm_unmap_detach+0x15e sys/uvm/uvm_map.c:1364
uvmspace_exec(ffff800035fe6fb0,1000,7f7fffffc000) at uvmspace_exec+0x3b7 sys/uvm/uvm_map.c:3393
sys_execve(ffff800035fe6fb0,ffff80003c438070,ffff80003c437fc0) at sys_execve+0xc31 sys/kern/kern_exec.c:453
syscall(ffff80003c438070) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80003c438070) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7255a3cbf710, count: -9
ddb{0}> machine ddbcpu 1
Stopped at x86_ipi_db+0x27: addq $0x8,%rsp
x86_ipi_db(ffff8000299edff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394
x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
__mp_lock(ffffffff83901040) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff83901040) at __mp_lock+0x192 sys/kern/kern_lock.c:173
ktrstruct(ffff80002a273c98,ffffffff833beafa,ffff80002a2ce150,20) at ktrstruct+0xdf sys/kern/kern_ktrace.c:313
sys_kevent(ffff80002a273c98,ffff80002a2ce4d0,ffff80002a2ce420) at sys_kevent+0x7bf sys/kern/kern_event.c:1327
syscall(ffff80002a2ce4d0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a2ce4d0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x79263f4839d0, count: 7
ddb{1}> trace
x86_ipi_db(ffff8000299edff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394
x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27
__mp_lock(ffffffff83901040) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:142 [inline]
__mp_lock(ffffffff83901040) at __mp_lock+0x192 sys/kern/kern_lock.c:173
ktrstruct(ffff80002a273c98,ffffffff833beafa,ffff80002a2ce150,20) at ktrstruct+0xdf sys/kern/kern_ktrace.c:313
sys_kevent(ffff80002a273c98,ffff80002a2ce4d0,ffff80002a2ce420) at sys_kevent+0x7bf sys/kern/kern_event.c:1327
syscall(ffff80002a2ce4d0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a2ce4d0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x79263f4839d0, count: -8