login: panic: kernel diagnostic assertion "len >= 0 && !M_READONLY(m)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/uipc_mbuf.c", line 1384
Stopped at db_enter+0x18: addq $0x8,%rsp
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*461008 76867 0 0 0 0K syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440
panic(ffffffff82579a90) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff825ec6cc,ffffffff82560ab1,568,ffffffff8258f284) at __assert+0x25 sys/kern/subr_prf.c:161
m_align(fffffd806d18bf00,ffffffd8) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385
bpf_movein(ffff8000212221b8,ffff800000ba5800,ffff800021221f18,ffff800021221e18) at bpf_movein+0x25e sys/net/bpf.c:228
bpfwrite(31700,ffff8000212221b8,1) at bpfwrite+0x169 sys/net/bpf.c:644
spec_write(ffff800021222010) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806a97fcc0,ffff8000212221b8,1,fffffd807f7d8840) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245
vn_write(fffffd806ee8eee0,ffff8000212221b8,0) at vn_write+0x157 sys/kern/vfs_vnops.c:414
dofilewritev(ffff80002117fa40,3,ffff8000212221b8,0,ffff8000212222b0) at dofilewritev+0x19c sys/kern/sys_generic.c:381
sys_write(ffff80002117fa40,ffff800021222258,ffff8000212222b0) at sys_write+0x83 sys/kern/sys_generic.c:301
syscall(ffff800021222320) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800021222320) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffda0d0, count: 2
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: kernel diagnostic assertion "len >= 0 && !M_READONLY(m)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/uipc_mbuf.c", line 1384
ddb{0}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440
panic(ffffffff82579a90) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff825ec6cc,ffffffff82560ab1,568,ffffffff8258f284) at __assert+0x25 sys/kern/subr_prf.c:161
m_align(fffffd806d18bf00,ffffffd8) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385
bpf_movein(ffff8000212221b8,ffff800000ba5800,ffff800021221f18,ffff800021221e18) at bpf_movein+0x25e sys/net/bpf.c:228
bpfwrite(31700,ffff8000212221b8,1) at bpfwrite+0x169 sys/net/bpf.c:644
spec_write(ffff800021222010) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806a97fcc0,ffff8000212221b8,1,fffffd807f7d8840) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245
vn_write(fffffd806ee8eee0,ffff8000212221b8,0) at vn_write+0x157 sys/kern/vfs_vnops.c:414
dofilewritev(ffff80002117fa40,3,ffff8000212221b8,0,ffff8000212222b0) at dofilewritev+0x19c sys/kern/sys_generic.c:381
sys_write(ffff80002117fa40,ffff800021222258,ffff8000212222b0) at sys_write+0x83 sys/kern/sys_generic.c:301
syscall(ffff800021222320) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800021222320) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffda0d0, count: -13
ddb{0}> show registers
rdi 0
rsi 0x1
rbp 0xffff800021221c30
rbx 0xffffffff828ecbff cpu_info_full_primary+0x2bff
rdx 0x3fd
rcx 0
rax 0x94
r8 0x101010101010101
r9 0x8080808080808080
r10 0xf438738fe98bdd8a
r11 0x420a457ad6ef2cfd
r12 0xffffffff828eca00 cpu_info_full_primary+0x2a00
r13 0
r14 0
r15 0x1
rip 0xffffffff82237da8 db_enter+0x18
cs 0x8
rflags 0x246
rsp 0xffff800021221c20
ss 0x10
db_enter+0x18: addq $0x8,%rsp
ddb{0}> show proc
PROC (syz-executor.0) pid=461008 stat=onproc
flags process=0 proc=0
pri=51, usrpri=51, nice=20
forw=0xffffffffffffffff, list=0xffff80002117efc0,0xffffffff82af1e70
process=0xffff8000ffffa998 user=0xffff80002121d000, vmspace=0xfffffd807effe170
estcpu=36, cpticks=1, pctcpu=0.0
user=0, sys=1, intr=0
ddb{0}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
*76867 461008 35022 0 7 0 syz-executor.0
35022 483890 40648 0 3 0x82 nanoslp syz-executor.0
40648 475655 93427 0 3 0x82 thrsleep syz-execprog
40648 295286 93427 0 3 0x4000082 nanoslp syz-execprog
40648 181005 93427 0 3 0x4000082 thrsleep syz-execprog
40648 146324 93427 0 3 0x4000082 thrsleep syz-execprog
40648 221204 93427 0 3 0x4000082 thrsleep syz-execprog
40648 43414 93427 0 3 0x4000082 kqread syz-execprog
40648 12190 93427 0 3 0x4000082 nanoslp syz-execprog
40648 336307 93427 0 3 0x4000082 thrsleep syz-execprog
40648 423255 93427 0 3 0x4000082 thrsleep syz-execprog
93427 345247 62554 0 3 0x10008a sigsusp ksh
62554 292549 64296 0 3 0x9a kqread sshd
30353 356292 1 0 3 0x100083 ttyin getty
64296 194040 1 0 3 0x88 kqread sshd
71028 91678 64739 74 3 0x100092 bpf pflogd
64739 53861 1 0 3 0x80 netio pflogd
73706 445760 68314 73 3 0x100090 kqread syslogd
68314 73110 1 0 3 0x100082 netio syslogd
10423 200274 1 0 3 0x100080 kqread resolvd
82570 40094 16919 77 3 0x100092 kqread dhcpleased
47467 400333 16919 77 3 0x100092 kqread dhcpleased
16919 176281 1 0 3 0x80 kqread dhcpleased
37944 513673 0 0 3 0x14200 bored smr
60495 441874 0 0 3 0x14200 pgzero zerothread
71560 485853 0 0 3 0x14200 aiodoned aiodoned
81292 241414 0 0 3 0x14200 syncer update
7501 11826 0 0 3 0x14200 cleaner cleaner
46357 109891 0 0 3 0x14200 reaper reaper
22565 258476 0 0 3 0x14200 pgdaemon pagedaemon
53946 73429 0 0 3 0x14200 bored viomb
1868 281327 0 0 3 0x40014200 acpi0 acpi0
23161 492915 0 0 7 0x40014200 idle1
66532 25174 0 0 3 0x14200 bored softnet
24066 282312 0 0 3 0x14200 bored systqmp
10099 383972 0 0 3 0x14200 bored systq
51644 476929 0 0 3 0x40014200 bored softclock
23866 400964 0 0 3 0x40014200 idle0
1 223563 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{0}> show all locks
Process 76867 (syz-executor.0) thread 0xffff80002117fa40 (461008)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82ac44c8)
#0 witness_lock+0x44d
#1 vn_write+0x42 sys/kern/vfs_vnops.c:399
#2 dofilewritev+0x19c sys/kern/sys_generic.c:381
#3 sys_write+0x83 sys/kern/sys_generic.c:301
#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{0}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 10156 6522K 6522K 78643K 11246 0
pcb 13 8K 8K 78643K 13 0
rtable 84 2K 3K 78643K 142 0
ifaddr 37 9K 9K 78643K 40 0
counters 42 33K 33K 78643K 42 0
ioctlops 0 0K 4K 78643K 1480 0
mount 1 1K 1K 78643K 1 0
log 0 0K 0K 78643K 5 0
vnodes 1168 73K 73K 78643K 1181 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 3 8K 12K 78643K 18 0
proc 67 87K 99K 78643K 310 0
NFS srvsock 1 0K 0K 78643K 1 0
NFS daemon 1 16K 16K 78643K 1 0
in_multi 22 1K 1K 78643K 22 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 25 122K 122K 78643K 25 0
exec 0 0K 2K 78643K 481 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 135 15K 15K 78643K 2471 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 7 0K 0K 78643K 7 0
temp 29 4686K 4749K 78643K 3452 0
kqueue 12 18K 18K 78643K 25 0
SYN cache 2 16K 16K 78643K 2 0
ddb{0}> 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 19 0 16 1 0 1 1 0 8 0
rtentry 112 34 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 1 0 1 1 0 8 1
tcpcb 736 8 0 5 1 0 1 1 0 8 0
arp 120 4 0 0 1 0 1 1 0 8 0
inpcb 304 36 0 30 1 0 1 1 0 8 0
nd6 48 3 0 0 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 10 0 0 1 0 1 1 0 8 0
pfstkey 112 10 0 0 1 0 1 1 0 8 0
pfstate 320 10 0 0 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 256 144 0 0 9 0 9 9 0 8 0
art_table 32 145 0 0 2 0 2 2 0 8 0
art_node 16 33 0 3 1 0 1 1 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 1451 0 49 88 0 88 88 0 8 0
ffsino 272 1451 0 49 94 0 94 94 0 8 0
nchpl 144 1679 0 59 60 0 60 60 0 8 0
uvmvnodes 80 1462 0 0 30 0 30 30 0 8 0
vnodes 224 1462 0 0 86 0 86 86 0 8 0
namei 1024 5145 0 5145 2 0 2 2 0 8 2
percpumem 16 33 0 0 1 0 1 1 0 8 0
scxspl 216 5217 0 5217 2 1 1 2 0 8 1
plimitpl 152 17 0 9 1 0 1 1 0 8 0
sigapl 424 347 0 316 5 0 5 5 0 8 1
knotepl 120 62 0 0 2 0 2 2 0 8 0
kqueuepl 216 21 0 13 1 0 1 1 0 8 0
pipepl 336 106 0 99 1 0 1 1 0 8 0
fdescpl 496 333 0 316 4 0 4 4 0 8 1
filepl 152 1350 0 1279 4 0 4 4 0 8 1
lockfpl 104 7 0 4 1 0 1 1 0 8 0
lockfspl 48 5 0 2 1 0 1 1 0 8 0
sessionpl 144 19 0 9 1 0 1 1 0 8 0
pgrppl 48 19 0 9 1 0 1 1 0 8 0
ucredpl 96 69 0 57 1 0 1 1 0 8 0
zombiepl 144 316 0 316 1 0 1 1 0 8 1
processpl 1064 347 0 316 3 0 3 3 0 8 0
procpl 672 355 0 316 4 0 4 4 0 8 0
sockpl 480 90 0 66 4 0 4 4 0 8 0
mcl8k 8192 4 0 0 1 0 1 1 0 8 0
mcl4k 4096 4 0 0 1 0 1 1 0 8 0
mcl2k 2048 80 0 0 10 0 10 10 0 8 0
mtagpl 96 3 0 0 1 0 1 1 0 8 0
mbufpl 256 132 0 0 9 0 9 9 0 8 0
bufpl 288 3561 0 142 245 0 245 245 0 8 0
anonpl 24 48990 0 45295 49 4 45 46 0 186 19
amapchunkpl 152 4843 0 4526 21 1 20 20 0 158 6
amappl16 200 123 0 68 5 1 4 4 0 8 0
amappl15 192 83 0 79 1 0 1 1 0 8 0
amappl14 184 2 0 1 1 0 1 1 0 8 0
amappl13 176 50 0 48 1 0 1 1 0 8 0
amappl12 168 8 0 7 2 1 1 1 0 8 0
amappl11 160 50 0 34 1 0 1 1 0 8 0
amappl10 152 24 0 19 1 0 1 1 0 8 0
amappl9 144 437 0 435 1 0 1 1 0 8 0
amappl8 136 429 0 408 1 0 1 1 0 8 0
amappl7 128 90 0 79 1 0 1 1 0 8 0
amappl6 120 187 0 168 2 0 2 2 0 8 1
amappl5 112 169 0 155 1 0 1 1 0 8 0
amappl4 104 693 0 670 2 0 2 2 0 8 1
amappl3 96 147 0 136 1 0 1 1 0 8 0
amappl2 88 470 0 428 3 0 3 3 0 8 2
amappl1 80 9720 0 9285 19 0 19 19 0 8 10
amappl 88 2137 0 2035 4 0 4 4 0 92 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 128 253 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 24 333 0 316 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 333 0 316 1 0 1 1 0 8 0
vmmpekpl 168 8032 0 8012 2 0 2 2 0 8 1
vmmpepl 168 31528 0 30395 91 0 91 91 0 357 41
vmsppl 368 332 0 316 3 0 3 3 0 8 1
rwobjpl 56 10813 0 8621 41 0 41 41 0 8 6
pdppl 4096 673 0 632 67 10 57 57 0 8 16
pvpl 32 215557 0 208905 261 0 261 261 0 265 203
pmappl 248 332 0 316 2 0 2 2 0 8 0
extentpl 40 58 0 38 1 0 1 1 0 8 0
phpool 112 540 0 13 16 0 16 16 0 8 0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440
panic(ffffffff82579a90) at panic+0x177 sys/kern/subr_prf.c:202
__assert(ffffffff825ec6cc,ffffffff82560ab1,568,ffffffff8258f284) at __assert+0x25 sys/kern/subr_prf.c:161
m_align(fffffd806d18bf00,ffffffd8) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385
bpf_movein(ffff8000212221b8,ffff800000ba5800,ffff800021221f18,ffff800021221e18) at bpf_movein+0x25e sys/net/bpf.c:228
bpfwrite(31700,ffff8000212221b8,1) at bpfwrite+0x169 sys/net/bpf.c:644
spec_write(ffff800021222010) at spec_write+0xd4 sys/kern/spec_vnops.c:309
VOP_WRITE(fffffd806a97fcc0,ffff8000212221b8,1,fffffd807f7d8840) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245
vn_write(fffffd806ee8eee0,ffff8000212221b8,0) at vn_write+0x157 sys/kern/vfs_vnops.c:414
dofilewritev(ffff80002117fa40,3,ffff8000212221b8,0,ffff8000212222b0) at dofilewritev+0x19c sys/kern/sys_generic.c:381
sys_write(ffff80002117fa40,ffff800021222258,ffff8000212222b0) at sys_write+0x83 sys/kern/sys_generic.c:301
syscall(ffff800021222320) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800021222320) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffda0d0, count: -13
ddb{0}> machine ddbcpu 1
Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp
x86_ipi_db(ffff800020ce8ff0) 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
acpicpu_idle() at acpicpu_idle+0x312 sys/dev/acpi/acpicpu.c:1206
sched_idle(ffff800020ce8ff0) at sched_idle+0x417 sys/kern/kern_sched.c:178
end trace frame: 0x0, count: 10
ddb{1}> trace
x86_ipi_db(ffff800020ce8ff0) 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
acpicpu_idle() at acpicpu_idle+0x312 sys/dev/acpi/acpicpu.c:1206
sched_idle(ffff800020ce8ff0) at sched_idle+0x417 sys/kern/kern_sched.c:178
end trace frame: 0x0, count: -5
ddb{1}>