panic: kernel diagnostic assertion "TAILQ_EMPTY(&lock->lf_blkhd)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/vfs_lockf.c", line 205
Stopped at db_enter+0x18: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*248667 45803 0 0x2 0x4000000 1 syz-executor1646560472
513316 36606 0 0x14000 0x40000200 0 softclock
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff8259eac4) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff82612e18,ffffffff8256ffc8,cd,ffffffff825f2f93) at __assert+0x25 sys/kern/subr_prf.c:161
lf_free(fffffd806f00d820) at lf_free+0xe2 ls_rele sys/kern/vfs_lockf.c:152 [inline]
lf_free(fffffd806f00d820) at lf_free+0xe2 sys/kern/vfs_lockf.c:208
lf_setlock(fffffd806f00d820) at lf_setlock+0xb54
lf_advlock(ffff800000bd5ba0,0,fffffd806f9e35e0,8,ffff8000211d01e0,50) at lf_advlock+0x3a7 sys/kern/vfs_lockf.c:301
VOP_ADVLOCK(fffffd806f2f1168,fffffd806f9e35e0,8,ffff8000211d01e0,50) at VOP_ADVLOCK+0x71 sys/kern/vfs_vops.c:628
sys_fcntl(ffff8000211337a8,ffff8000211d0268,ffff8000211d02c0) at sys_fcntl+0xad9
syscall(ffff8000211d0330) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff8000211d0330) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xfe52fd01790, count: 5
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
*cpu1: kernel diagnostic assertion "TAILQ_EMPTY(&lock->lf_blkhd)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/vfs_lockf.c", line 205
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff8259eac4) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff82612e18,ffffffff8256ffc8,cd,ffffffff825f2f93) at __assert+0x25 sys/kern/subr_prf.c:161
lf_free(fffffd806f00d820) at lf_free+0xe2 ls_rele sys/kern/vfs_lockf.c:152 [inline]
lf_free(fffffd806f00d820) at lf_free+0xe2 sys/kern/vfs_lockf.c:208
lf_setlock(fffffd806f00d820) at lf_setlock+0xb54
lf_advlock(ffff800000bd5ba0,0,fffffd806f9e35e0,8,ffff8000211d01e0,50) at lf_advlock+0x3a7 sys/kern/vfs_lockf.c:301
VOP_ADVLOCK(fffffd806f2f1168,fffffd806f9e35e0,8,ffff8000211d01e0,50) at VOP_ADVLOCK+0x71 sys/kern/vfs_vops.c:628
sys_fcntl(ffff8000211337a8,ffff8000211d0268,ffff8000211d02c0) at sys_fcntl+0xad9
syscall(ffff8000211d0330) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff8000211d0330) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xfe52fd01790, count: -10
ddb{1}> show registers
rdi 0
rsi 0x1
rbp 0xffff8000211cfed0
rbx 0xffff800020cd9c5f
rdx 0x3fd
rcx 0
rax 0x95
r8 0x101010101010101
r9 0x8080808080808080
r10 0x8f59cff0ae48494c
r11 0x4b323472889c2c58
r12 0xffff800020cd9a60
r13 0
r14 0
r15 0x1
rip 0xffffffff8232f328 db_enter+0x18
cs 0x8
rflags 0x246
rsp 0xffff8000211cfec0
ss 0x10
db_enter+0x18: addq $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor1646560472) pid=248667 stat=onproc
flags process=2<EXEC> proc=4000000<THREAD>
pri=51, usrpri=51, nice=20
forw=0xffffffffffffffff, list=0xffff800021133508,0xffffffff82a71a88
process=0xffff8000ffff2150 user=0xffff8000211cb000, vmspace=0xfffffd806ee28cf8
estcpu=1, cpticks=1, pctcpu=0.0
user=0, sys=1, intr=0
ddb{1}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
45803 181252 8746 0 2 0x2 syz-executor1646560472
45803 412490 8746 0 3 0x4000082 lockf syz-executor1646560472
*45803 248667 8746 0 7 0x4000002 syz-executor1646560472
8746 428688 85654 0 3 0x10008a sigsusp ksh
85654 361334 6831 0 3 0x9a kqread sshd
82937 443237 1 0 3 0x100083 ttyin getty
6831 465766 1 0 3 0x88 kqread sshd
38156 297837 94233 74 3 0x1100092 bpf pflogd
94233 108865 1 0 3 0x80 netio pflogd
25665 46763 48807 73 3 0x1100090 kqread syslogd
48807 264616 1 0 3 0x100082 netio syslogd
28566 9258 1 0 3 0x100080 kqread resolvd
43316 269921 46340 77 3 0x100092 kqread dhcpleased
67919 126187 46340 77 3 0x100092 kqread dhcpleased
46340 11628 1 0 3 0x80 kqread dhcpleased
89739 517763 0 0 3 0x14200 bored smr
78840 499733 0 0 3 0x14200 pgzero zerothread
76184 108284 0 0 3 0x14200 aiodoned aiodoned
82654 166304 0 0 3 0x14200 syncer update
60371 207094 0 0 3 0x14200 cleaner cleaner
1336 348496 0 0 3 0x14200 reaper reaper
33450 131860 0 0 3 0x14200 pgdaemon pagedaemon
53770 402640 0 0 3 0x14200 bored viomb
484 482512 0 0 3 0x40014200 acpi0 acpi0
94375 390900 0 0 3 0x40014200 idle1
8613 461462 0 0 3 0x14200 bored softnet
92139 109372 0 0 3 0x14200 bored softnet
89291 80560 0 0 3 0x14200 bored softnet
21318 245210 0 0 3 0x14200 bored softnet
32096 485507 0 0 3 0x14200 bored systqmp
87250 282009 0 0 3 0x14200 bored systq
36606 513316 0 0 7 0x40014200 softclock
18575 14753 0 0 3 0x40014200 idle0
1 353896 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{1}> show all locks
Process 45803 (syz-executor1646560472) thread 0xffff8000211337a8 (248667)
exclusive rwlock lockflk r = 0 (0xffffffff829ae930)
#0 witness_lock+0x44d
#1 lf_advlock+0x189 sys/kern/vfs_lockf.c:263
#2 VOP_ADVLOCK+0x71 sys/kern/vfs_vops.c:628
#3 sys_fcntl+0xad9
#4 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#4 syscall+0x489 sys/arch/amd64/amd64/trap.c:585
#5 Xsyscall+0x128
ddb{1}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 10153 6455K 6456K 78643K 11243 0
pcb 13 8K 8K 78643K 13 0
rtable 58 1K 2K 78643K 108 0
ifaddr 29 8K 8K 78643K 32 0
counters 40 33K 33K 78643K 40 0
ioctlops 0 0K 4K 78643K 1479 0
mount 1 1K 1K 78643K 1 0
log 0 0K 0K 78643K 5 0
vnodes 1167 73K 73K 78643K 1180 0
UFS quota 1 32K 32K 78643K 1 0
UFS mount 5 36K 36K 78643K 5 0
shm 2 1K 1K 78643K 2 0
VM map 2 1K 1K 78643K 2 0
sem 2 0K 0K 78643K 2 0
dirhash 12 2K 2K 78643K 12 0
ACPI 1697 195K 286K 78643K 12548 0
file desc 2 2K 3K 78643K 4 0
proc 67 91K 91K 78643K 282 0
NFS srvsock 1 0K 0K 78643K 1 0
NFS daemon 1 16K 16K 78643K 1 0
in_multi 11 0K 0K 78643K 11 0
ether_multi 1 0K 0K 78643K 1 0
ISOFS mount 1 32K 32K 78643K 1 0
MSDOSFS mount 1 16K 16K 78643K 1 0
ttys 31 148K 148K 78643K 31 0
exec 0 0K 2K 78643K 432 0
tdb 3 0K 0K 78643K 3 0
pagedep 1 8K 8K 78643K 1 0
inodedep 1 32K 32K 78643K 1 0
newblk 1 0K 0K 78643K 1 0
VM swap 7 26K 26K 78643K 7 0
UVM amap 62 3K 5K 78643K 1559 0
UVM aobj 3 2K 2K 78643K 3 0
memdesc 1 4K 4K 78643K 1 0
crypto data 1 1K 1K 78643K 1 0
NDP 4 0K 0K 78643K 4 0
temp 23 4713K 4777K 78643K 2516 0
kqueue 11 16K 18K 78643K 24 0
SYN cache 2 16K 16K 78643K 2 0
ddb{1}> show all pools
Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
plcache 128 22 0 0 1 0 1 1 0 8 0
rtpcb 120 17 0 14 1 0 1 1 0 8 0
rtentry 112 23 0 1 1 0 1 1 0 8 0
unpcb 136 35 0 20 1 0 1 1 0 8 0
syncache 296 5 0 5 2 1 1 1 0 8 1
tcpcb 736 8 0 5 1 0 1 1 0 8 0
arp 120 2 0 0 1 0 1 1 0 8 0
inpcb 312 32 0 26 1 0 1 1 0 8 0
pfosfp 40 1428 0 1005 5 0 5 5 0 8 0
pfosfpen 112 1428 0 714 21 0 21 21 0 8 0
pfstitem 24 9 0 2 1 0 1 1 0 8 0
pfstkey 112 9 0 2 1 0 1 1 0 8 0
pfstate 336 9 0 2 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 96 0 0 6 0 6 6 0 8 0
art_table 32 97 0 0 1 0 1 1 0 8 0
art_node 16 22 0 2 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1425 0 39 87 0 87 87 0 8 0
ffsino 272 1425 0 39 93 0 93 93 0 8 0
nchpl 144 1614 0 49 58 0 58 58 0 8 0
uvmvnodes 80 1435 0 0 30 0 30 30 0 8 0
vnodes 224 1435 0 0 85 0 85 85 0 8 0
namei 1024 4476 0 4476 2 1 1 1 0 8 1
percpumem 16 32 0 0 1 0 1 1 0 8 0
kstatmem 264 8 0 0 1 0 1 1 0 8 0
scxspl 216 4067 0 4067 10 4 6 8 0 8 6
plimitpl 152 16 0 9 1 0 1 1 0 8 0
sigapl 424 323 0 291 5 1 4 5 0 8 0
knotepl 120 50 0 0 2 0 2 2 0 8 0
kqueuepl 216 20 0 13 1 0 1 1 0 8 0
pipepl 336 86 0 83 2 1 1 1 0 8 0
fdescpl 496 306 0 291 3 0 3 3 0 8 0
filepl 152 1185 0 1125 3 0 3 3 0 8 0
lockfpl 104 11 0 6 1 0 1 1 0 8 0
lockfspl 48 5 0 2 1 0 1 1 0 8 0
sessionpl 144 18 0 9 1 0 1 1 0 8 0
pgrppl 48 18 0 9 1 0 1 1 0 8 0
ucredpl 96 72 0 60 1 0 1 1 0 8 0
zombiepl 144 291 0 291 2 1 1 1 0 8 1
processpl 1064 323 0 291 3 0 3 3 0 8 0
procpl 672 325 0 291 4 1 3 4 0 8 0
sockpl 480 84 0 60 5 1 4 4 0 8 0
mcl8k 8192 4 0 0 1 0 1 1 0 8 0
mcl4k 4096 5 0 0 1 0 1 1 0 8 0
mcl2k 2048 64 0 0 8 0 8 8 0 8 0
mtagpl 96 3 0 0 1 0 1 1 0 8 0
mbufpl 256 115 0 0 7 0 7 7 0 8 0
bufpl 288 2021 0 90 138 0 138 138 0 8 0
anonpl 24 39056 0 36911 18 4 14 15 0 186 1
amapchunkpl 152 2868 0 2761 7 2 5 6 0 158 0
amappl16 200 97 0 92 1 0 1 1 0 8 0
amappl15 192 1 0 0 1 0 1 1 0 8 0
amappl14 184 1 0 1 1 1 0 1 0 8 0
amappl13 176 34 0 33 2 1 1 1 0 8 0
amappl12 168 3 0 3 2 1 1 1 0 8 1
amappl11 160 66 0 49 1 0 1 1 0 8 0
amappl10 152 3 0 1 1 0 1 1 0 8 0
amappl9 144 497 0 495 1 0 1 1 0 8 0
amappl8 136 365 0 363 2 1 1 1 0 8 0
amappl7 128 52 0 49 1 0 1 1 0 8 0
amappl6 120 106 0 96 1 0 1 1 0 8 0
amappl5 112 91 0 79 1 0 1 1 0 8 0
amappl4 104 629 0 608 1 0 1 1 0 8 0
amappl3 96 398 0 373 1 0 1 1 0 8 0
amappl2 88 454 0 416 1 0 1 1 0 8 0
amappl1 80 9451 0 9025 12 2 10 10 0 8 0
amappl 88 1278 0 1235 2 1 1 2 0 92 0
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 128 253 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 18 0 17 1 0 1 1 0 8 0
aobjpl 72 2 0 0 1 0 1 1 0 8 0
uaddrrnd 24 306 0 291 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 306 0 291 1 0 1 1 0 8 0
vmmpekpl 168 6217 0 6206 1 0 1 1 0 8 0
vmmpepl 168 27089 0 26176 45 3 42 42 0 357 2
vmsppl 368 305 0 291 2 0 2 2 0 8 0
rwobjpl 56 9732 0 7700 30 0 30 30 0 8 0
pdppl 4096 619 0 582 57 20 37 45 0 8 0
pvpl 32 131573 0 127433 43 7 36 36 0 265 2
pmappl 248 305 0 291 2 0 2 2 0 8 0
extentpl 40 58 0 38 1 0 1 1 0 8 0
phpool 112 416 0 25 12 0 12 12 0 8 0
ddb{1}> machine ddbcpu 0
Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp
x86_ipi_db(ffffffff8297aff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__mp_lock(ffffffff82a369e0) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82a369e0) at __mp_lock+0x122 sys/kern/kern_lock.c:147
__mp_acquire_count(ffffffff82a369e0,1) at __mp_acquire_count+0x48 sys/kern/kern_lock.c:227
mi_switch() at mi_switch+0x3d3 sys/kern/sched_bsd.c:416
sleep_finish(ffff8000210f5158,1) at sleep_finish+0x180 sys/kern/kern_synch.c:420
softclock_thread(ffff8000210e9500) at softclock_thread+0xd9 sys/kern/kern_timeout.c:797
end trace frame: 0x0, count: 7
ddb{0}> trace
x86_ipi_db(ffffffff8297aff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
__mp_lock(ffffffff82a369e0) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82a369e0) at __mp_lock+0x122 sys/kern/kern_lock.c:147
__mp_acquire_count(ffffffff82a369e0,1) at __mp_acquire_count+0x48 sys/kern/kern_lock.c:227
mi_switch() at mi_switch+0x3d3 sys/kern/sched_bsd.c:416
sleep_finish(ffff8000210f5158,1) at sleep_finish+0x180 sys/kern/kern_synch.c:420
softclock_thread(ffff8000210e9500) at softclock_thread+0xd9 sys/kern/kern_timeout.c:797
end trace frame: 0x0, count: -8
ddb{0}> machine ddbcpu 1
Stopped at db_enter+0x18: addq $0x8,%rsp
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff8259eac4) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff82612e18,ffffffff8256ffc8,cd,ffffffff825f2f93) at __assert+0x25 sys/kern/subr_prf.c:161
lf_free(fffffd806f00d820) at lf_free+0xe2 ls_rele sys/kern/vfs_lockf.c:152 [inline]
lf_free(fffffd806f00d820) at lf_free+0xe2 sys/kern/vfs_lockf.c:208
lf_setlock(fffffd806f00d820) at lf_setlock+0xb54
lf_advlock(ffff800000bd5ba0,0,fffffd806f9e35e0,8,ffff8000211d01e0,50) at lf_advlock+0x3a7 sys/kern/vfs_lockf.c:301
VOP_ADVLOCK(fffffd806f2f1168,fffffd806f9e35e0,8,ffff8000211d01e0,50) at VOP_ADVLOCK+0x71 sys/kern/vfs_vops.c:628
sys_fcntl(ffff8000211337a8,ffff8000211d0268,ffff8000211d02c0) at sys_fcntl+0xad9
syscall(ffff8000211d0330) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff8000211d0330) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xfe52fd01790, count: 5
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff8259eac4) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff82612e18,ffffffff8256ffc8,cd,ffffffff825f2f93) at __assert+0x25 sys/kern/subr_prf.c:161
lf_free(fffffd806f00d820) at lf_free+0xe2 ls_rele sys/kern/vfs_lockf.c:152 [inline]
lf_free(fffffd806f00d820) at lf_free+0xe2 sys/kern/vfs_lockf.c:208
lf_setlock(fffffd806f00d820) at lf_setlock+0xb54
lf_advlock(ffff800000bd5ba0,0,fffffd806f9e35e0,8,ffff8000211d01e0,50) at lf_advlock+0x3a7 sys/kern/vfs_lockf.c:301
VOP_ADVLOCK(fffffd806f2f1168,fffffd806f9e35e0,8,ffff8000211d01e0,50) at VOP_ADVLOCK+0x71 sys/kern/vfs_vops.c:628
sys_fcntl(ffff8000211337a8,ffff8000211d0268,ffff8000211d02c0) at sys_fcntl+0xad9
syscall(ffff8000211d0330) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff8000211d0330) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xfe52fd01790, count: -10
ddb{1}>