protection_fault: in6_addmulti (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1e5b016c5082 sync for __syscall removal
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=10c32528c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=dbe4b5a3f404f47bd764

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/cb9a404e2563/disk-1e5b016c.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/27dc2036237a/bsd-1e5b016c.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ea0ea667b9fa/kernel-1e5b016c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dbe4b5...@syzkaller.appspotmail.com

kernel: protection fault trap, code=0
Stopped at in6_addmulti+0xc4: movzbl 0x1(%rax),%ebx
ddb{1}>
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
the kernel did not panic
ddb{1}> trace
in6_addmulti(ffff800024b2f2e8,ffff800000d0b800,ffff800024b2f37c) at in6_addmulti+0xc4 sys/netinet6/in6.c:1037
in6_update_ifa(ffff800000d0b800,ffff800024b2f3f0,0) at in6_update_ifa+0x1418 in6_joingroup sys/netinet6/in6.c:1154 [inline]
in6_update_ifa(ffff800000d0b800,ffff800024b2f3f0,0) at in6_update_ifa+0x1418 sys/netinet6/in6.c:776
in6_ifattach_linklocal(ffff800000d0b800,0) at in6_ifattach_linklocal+0x28d sys/netinet6/in6_ifattach.c:281
in6_ifattach(ffff800000d0b800) at in6_ifattach+0x1bb sys/netinet6/in6_ifattach.c:405
ifnewlladdr(ffff800000d0b800) at ifnewlladdr+0x180 sys/net/if.c:3204
ifioctl(fffffd80641e53d8,8020691f,ffff800024b2f650,ffff8000211e8b40) at ifioctl+0x1f5e sys/net/if.c:2253
sys_ioctl(ffff8000211e8b40,ffff800024b2f768,ffff800024b2f7b0) at sys_ioctl+0x4a2
syscall(ffff800024b2f830) at syscall+0x606 mi_syscall sys/sys/syscall_mi.h:110 [inline]
syscall(ffff800024b2f830) at syscall+0x606 sys/arch/amd64/amd64/trap.c:625
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xb90fbeb3460, count: -9
ddb{1}> show registers
rdi 0xffff80002430c000
rsi 0x4a80 __ALIGN_SIZE+0x3a80
rbp 0xffff800024b2f1d0
rbx 0
rdx 0xffff80002430c000
rcx 0x4a7f __ALIGN_SIZE+0x3a7f
rax 0xdeaf0036deaf4152
r8 0x2
r9 0x16d5b805
r10 0x52b606d257e14acb
r11 0x5bb3b7e9c0d9b46f
r12 0xffff800000e1f480
r13 0xffff800024b2f2e8
r14 0xffff800024b2f37c
r15 0xffff800000d0b800
rip 0xffffffff810e3c54 in6_addmulti+0xc4
cs 0x8
rflags 0x10282 __ALIGN_SIZE+0xf282
rsp 0xffff800024b2f050
ss 0
in6_addmulti+0xc4: movzbl 0x1(%rax),%ebx
ddb{1}> show proc
PROC (syz-executor.3) pid=429091 stat=onproc
flags process=0 proc=4000000<THREAD>
pri=32, usrpri=83, nice=20
forw=0xffffffffffffffff, list=0xffff80002120f928,0xffffffff82ca0df8
process=0xffff800021297688 user=0xffff800024b2a000, vmspace=0xfffffd806f0c88a0
estcpu=33, cpticks=0, pctcpu=0.0
user=0, sys=0, intr=0
ddb{1}> ps
PID TID PPID UID S FLAGS WAIT COMMAND
42288 76623 54803 0 2 0x480 syz-executor.2
42288 39038 54803 0 2 0x4000000 syz-executor.2
42288 462655 54803 0 3 0x4000080 fsleep syz-executor.2
48413 162719 23741 0 2 0 syz-executor.3
48413 199484 23741 0 3 0x4000000 smrbar syz-executor.3
*48413 429091 23741 0 7 0x4000000 syz-executor.3
3430 28104 57317 0 3 0x82 piperd syz-executor.0
54803 335265 57317 0 7 0x3 syz-executor.2
23741 80242 57317 0 3 0x82 nanoslp syz-executor.3
93488 23846 57317 0 3 0x82 piperd syz-executor.6
82323 41590 0 0 3 0x14280 nfsidl nfsio
68841 407662 0 0 3 0x14280 nfsidl nfsio
9288 81725 0 0 3 0x14280 nfsidl nfsio
36936 473621 0 0 3 0x14280 nfsidl nfsio
1112 59222 0 0 3 0x14280 nfsidl nfsio
7552 82367 0 0 3 0x14280 nfsidl nfsio
16115 474705 0 0 3 0x14280 nfsidl nfsio
61616 67967 0 0 3 0x14280 nfsidl nfsio
46564 418868 0 0 3 0x14280 nfsidl nfsio
80652 329802 0 0 3 0x14280 nfsidl nfsio
56261 507924 0 0 3 0x14280 nfsidl nfsio
3818 187172 0 0 3 0x14280 nfsidl nfsio
52620 116226 0 0 3 0x14280 nfsidl nfsio
62144 58127 0 0 3 0x14280 nfsidl nfsio
78773 208262 0 0 3 0x14280 nfsidl nfsio
38734 63645 0 0 3 0x14280 nfsidl nfsio
89087 494568 0 0 3 0x14280 nfsidl nfsio
98379 852 0 0 3 0x14280 nfsidl nfsio
1771 363568 0 0 3 0x14280 nfsidl nfsio
43763 5924 0 0 3 0x14280 nfsidl nfsio
78504 452089 57317 0 3 0x82 piperd syz-executor.1
22543 221145 57317 0 3 0x82 nanoslp syz-executor.5
96848 13932 57317 0 2 0x2 syz-executor.4
47462 409289 57317 0 3 0x82 piperd syz-executor.7
63630 427484 1 0 3 0 vmmaplk syz-executor.7
63630 354633 1 0 3 0x4000080 fsleep syz-executor.7
63630 171527 1 0 3 0x4000080 fsleep syz-executor.7
63630 2736 1 0 3 0x4000000 vmmaplk syz-executor.7
43855 92230 1 0 3 0x100083 ttyin getty
7246 231895 0 0 3 0x14200 bored sosplice
57317 43853 30923 0 3 0x82 thrsleep syz-fuzzer
57317 71708 30923 0 3 0x4000082 nanoslp syz-fuzzer
57317 196289 30923 0 3 0x4000082 thrsleep syz-fuzzer
57317 351357 30923 0 3 0x4000082 wait syz-fuzzer
57317 109852 30923 0 3 0x4000082 thrsleep syz-fuzzer
57317 428619 30923 0 3 0x4000082 thrsleep syz-fuzzer
57317 369866 30923 0 3 0x4000082 wait syz-fuzzer
57317 382069 30923 0 3 0x4000082 thrsleep syz-fuzzer
57317 275720 30923 0 3 0x4000082 wait syz-fuzzer
57317 477018 30923 0 3 0x4000082 wait syz-fuzzer
57317 183379 30923 0 3 0x4000082 thrsleep syz-fuzzer
57317 51294 30923 0 3 0x4000082 kqread syz-fuzzer
57317 423944 30923 0 3 0x4000082 wait syz-fuzzer
57317 384498 30923 0 3 0x4000082 wait syz-fuzzer
57317 481682 30923 0 3 0x4000082 wait syz-fuzzer
57317 198301 30923 0 3 0x4000082 wait syz-fuzzer
30923 101328 13684 0 3 0x10008a sigsusp ksh
13684 228254 54139 0 3 0x9a kqread sshd
54139 289329 1 0 3 0x88 kqread sshd
30926 300749 26838 74 3 0x1100092 bpf pflogd
26838 485411 1 0 3 0x80 netio pflogd
70040 391681 34143 73 3 0x1100090 kqread syslogd
34143 211563 1 0 3 0x100082 netio syslogd
53850 140398 1 0 3 0x100080 kqread resolvd
6774 158786 0 0 3 0x14200 bored smr
76529 135892 0 0 2 0x14200 zerothread
62512 48669 0 0 3 0x14200 aiodoned aiodoned
44303 97132 0 0 3 0x14200 syncer update
64555 479568 0 0 3 0x14200 cleaner cleaner
14756 161647 0 0 3 0x14200 reaper reaper
36599 315273 0 0 3 0x14200 pgdaemon pagedaemon
75394 335887 0 0 3 0x14200 bored viomb
50639 363621 0 0 3 0x40014200 acpi0 acpi0
48493 282406 0 0 3 0x40014200 idle1
57344 96758 0 0 3 0x14200 bored softnet
33810 198108 0 0 3 0x14200 bored softnet
82156 335797 0 0 3 0x14200 bored softnet
75704 293993 0 0 3 0x14200 bored softnet
32711 344375 0 0 2 0x14200 systqmp
79171 323543 0 0 3 0x14200 bored systq
41079 375820 0 0 3 0x40014200 bored softclock
95912 309541 0 0 3 0x40014200 idle0
1 313819 0 0 3 0x82 wait init
0 0 -1 0 3 0x10200 scheduler swapper
ddb{1}> show all locks
ddb{1}> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 10223 6498K 7148K 78643K 16383 0
pcb 13 18K 23K 78643K 2136 0
rtable 206 16K 18K 78643K 2746 0
ifaddr 81 27K 30K 78643K 1115 0
sysctl 3 1K 3K 78643K 38 0
counters 58 35K 36K 78643K 884 0
ioctlops 0 0K 4K 78643K 2278 0
iov 0 0K 28K 78643K 1587 0
mount 1 1K 1K 78643K 1 0
log 0 0K 0K 78643K 4 0
vnodes 1646 103K 103K 78643K 6920 0
UFS quota 1 32K 32K 78643K 1 0
UFS mount 5 36K 36K 78643K 5 0
shm 3 5K 13K 78643K 125 0
VM map 2 1K 1K 78643K 2 0
sem 12 1K 1K 78643K 912 0
dirhash 12 2K 2K 78643K 12 0
ACPI 1697 195K 286K 78643K 12548 0
file desc 13 45K 81K 78643K 10468 0
sigio 0 0K 0K 78643K 150 0
proc 70 67K 128K 78643K 2370 0
subproc 117 7K 7K 78643K 715 0
NFS srvsock 1 0K 0K 78643K 1 0
NFS daemon 1 16K 16K 78643K 1 0
ip_moptions 0 0K 0K 78643K 562 0
in_multi 79 5K 7K 78643K 850 0
ether_multi 1 0K 0K 78643K 70 0
mrt 1 0K 0K 78643K 75 0
ISOFS mount 1 32K 32K 78643K 1 0
MSDOSFS mount 1 16K 16K 78643K 1 0
ttys 169 758K 758K 78643K 169 0
exec 0 0K 1K 78643K 1955 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 8 62K 64K 78643K 10 0
UVM amap 353 98K 109K 78643K 74012 0
UVM aobj 131 4K 4K 78643K 131 0
memdesc 1 4K 4K 78643K 1 0
crypto data 1 1K 1K 78643K 1 0
ip6_options 0 0K 0K 78643K 670 0
NDP 14 0K 1K 78643K 355 0
temp 141 5778K 6802K 78643K 154677 0
kqueue 8 11K 26K 78643K 761 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 1159 0 1158 19 18 1 5 0 8 0
rtentry 112 832 0 746 5 2 3 4 0 8 0
unpcb 144 8929 0 8856 94 88 6 10 0 8 3
syncache 296 43 0 43 10 10 0 1 0 8 0
tcpqe 32 237 0 237 7 7 0 2 0 8 0
tcpcb 776 9992 0 9986 180 172 8 14 0 8 7
arp 120 131 0 115 1 0 1 1 0 8 0
inpcb 368 17891 0 17882 197 190 7 20 0 8 5
nd6 48 181 0 161 1 0 1 1 0 8 0
pkpcb 40 105 0 105 10 10 0 1 0 8 0
kcovpl 48 55 0 46 1 0 1 1 0 8 0
mppekey 1024 6 0 6 2 2 0 1 0 8 0
ppxss 1256 260 0 260 20 20 0 1 0 8 0
pppxif 1456 132 0 132 15 15 0 1 0 8 0
pfstscr 40 3 0 3 1 1 0 1 0 8 0
pffrag 232 69 0 69 5 5 0 1 0 482 0
pffrnode 88 69 0 69 5 5 0 1 0 8 0
pffrent 40 279 0 279 5 5 0 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
pfanchor 1280 6 0 0 1 0 1 1 0 8 0
pfstitem 24 220 0 199 1 0 1 1 0 8 0
pfstkey 128 226 0 205 3 2 1 2 0 8 0
pfstate 384 223 0 202 11 8 3 7 0 8 0
pfrule 1344 21 0 16 2 1 1 2 0 8 0
rttmr 136 18 0 18 5 5 0 1 0 8 0
art_heap8 4096 2 0 1 2 1 1 2 0 8 0
art_heap4 256 3494 0 3047 56 28 28 30 0 8 0
art_table 32 3496 0 3048 4 0 4 4 0 8 0
art_node 16 830 0 752 1 0 1 1 0 8 0
sysvmsgpl 40 81 0 70 1 0 1 1 0 8 0
semupl 112 3 0 3 1 1 0 1 0 8 0
semapl 112 906 0 896 1 0 1 1 0 8 0
shmpl 112 128 0 0 4 0 4 4 0 8 0
dirhash 1024 17 0 0 3 0 3 3 0 8 0
dino2pl 256 15088 0 13595 94 0 94 94 0 8 0
ffsino 272 15088 0 13595 100 0 100 100 0 8 0
nchpl 144 30665 0 29016 63 0 63 63 0 8 0
rtmask 32 13 0 13 5 5 0 1 0 8 0
uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0
vnodes 216 5926 0 0 330 0 330 330 0 8 0
namei 1024 105968 0 105968 6 5 1 2 0 8 1
percpumem 16 455 0 413 1 0 1 1 0 8 0
vmpool 696 28 0 28 7 7 0 1 0 8 0
kstatmem 264 470 0 442 8 5 3 3 0 8 0
scsiplug 72 4 0 4 1 1 0 1 0 8 0
scxspl 216 90586 0 90586 33 32 1 8 0 8 1
plimitpl 152 1396 0 1380 1 0 1 1 0 8 0
sigapl 424 10867 0 10805 12 4 8 8 0 8 0
futexpl 64 98560 0 98557 5 4 1 1 0 8 0
knotepl 120 731 0 0 11 0 11 11 0 8 0
kqueuepl 216 2113 0 2107 47 44 3 5 0 8 2
pipepl 320 2839 0 2810 73 70 3 8 0 8 0
fdescpl 496 10668 0 10645 7 3 4 5 0 8 0
filepl 152 80457 0 80153 145 128 17 23 0 8 5
lockfpl 104 3836 0 3835 8 6 2 2 0 8 1
lockfspl 48 1311 0 1310 1 0 1 1 0 8 0
sessionpl 144 73 0 56 1 0 1 1 0 8 0
pgrppl 48 244 0 227 1 0 1 1 0 8 0
ucredpl 104 7596 0 7587 1 0 1 1 0 8 0
zombiepl 144 10806 0 10805 2 1 1 1 0 8 0
processpl 1072 10867 0 10805 6 1 5 5 0 8 0
procpl 696 30028 0 29944 23 13 10 10 0 8 0
srpgc 96 62 0 62 17 16 1 1 0 8 1
sosppl 168 94 0 94 18 17 1 1 0 8 1
sockpl 488 28203 0 28121 554 527 27 36 0 8 16
mcl64k 65536 21 0 0 3 0 3 3 0 8 0
mcl16k 16384 25 0 0 4 1 3 3 0 8 0
mcl12k 12288 25 0 0 2 0 2 2 0 8 0
mcl9k 9216 29 0 0 2 0 2 2 0 8 0
mcl8k 8192 50 0 0 3 0 3 3 0 8 0
mcl4k 4096 32 0 0 4 1 3 3 0 8 0
mcl2k2 2112 4 0 0 1 0 1 1 0 8 0
mcl2k 2048 499 0 0 57 28 29 57 0 8 0
mtagpl 96 93 0 0 3 0 3 3 0 8 0
mbufpl 256 1914 0 0 108 0 108 108 0 8 0
bufpl 288 21169 0 14841 453 0 453 453 0 8 0
anonpl 24 2216644 0 2199649 296 168 128 184 0 186 0
amapchunkpl 152 213889 0 213180 95 61 34 62 0 158 0
amappl16 200 21849 0 21301 148 115 33 43 0 8 0
amappl15 192 74 0 73 1 0 1 1 0 8 0
amappl14 184 320 0 306 3 2 1 2 0 8 0
amappl13 176 16 0 15 1 0 1 1 0 8 0
amappl12 168 990 0 986 1 0 1 1 0 8 0
amappl11 160 47 0 39 1 0 1 1 0 8 0
amappl10 152 96 0 79 1 0 1 1 0 8 0
amappl9 144 1026 0 1025 1 0 1 1 0 8 0
amappl8 136 668 0 548 5 0 5 5 0 8 0
amappl7 128 306 0 282 2 0 2 2 0 8 0
amappl6 120 515 0 494 2 1 1 2 0 8 0
amappl5 112 470 0 463 1 0 1 1 0 8 0
amappl4 104 1281 0 1246 2 1 1 2 0 8 0
amappl3 96 31758 0 31714 2 0 2 2 0 8 0
amappl2 88 11757 0 11694 4 2 2 4 0 8 0
amappl1 80 247252 0 246620 30 12 18 28 0 8 0
amappl 88 72666 0 72483 6 0 6 6 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 72 130 0 0 3 0 3 3 0 8 0
uaddrrnd 24 10696 0 10673 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 10696 0 10673 1 0 1 1 0 8 0
vmmpekpl 168 90415 0 90341 4 0 4 4 0 8 0
vmmpepl 168 996500 0 994039 341 201 140 163 0 357 0
vmsppl 440 10695 0 10673 5 1 4 4 0 8 0
rwobjpl 56 270379 0 262656 139 24 115 116 0 8 0
pdppl 4096 21399 0 21346 654 591 63 77 0 8 10
pvpl 32 4514985 0 4492324 674 460 214 366 0 265 0
pmappl 248 10695 0 10673 3 1 2 3 0 8 0
extentpl 40 56 0 38 1 0 1 1 0 8 0
phpool 112 1769 0 869 28 1 27 27 0 8 0
ddb{1}> machine ddbcpu 0
Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp
ddb{0}> trace
x86_ipi_db(ffffffff82b24ff0) 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(ffffffff82db6020) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline]
__mp_lock(ffffffff82db6020) at __mp_lock+0x122 sys/kern/kern_lock.c:147
ktrstruct(ffff8000211e8888,ffffffff827ee3fe,ffff800029377060,10) at ktrstruct+0xd6 sys/kern/kern_ktrace.c:307
sys_nanosleep(ffff8000211e8888,ffff8000293770d0,ffff800029377120) at sys_nanosleep+0xe0 sys/kern/kern_time.c:288
syscall(ffff8000293771a0) at syscall+0x606 mi_syscall sys/sys/syscall_mi.h:110 [inline]
syscall(ffff8000293771a0) at syscall+0x606 sys/arch/amd64/amd64/trap.c:625
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffffb790, count: -8
ddb{0}> machine ddbcpu 1
Stopped at in6_addmulti+0xc4: movzbl 0x1(%rax),%ebx
ddb{1}> trace
in6_addmulti(ffff800024b2f2e8,ffff800000d0b800,ffff800024b2f37c) at in6_addmulti+0xc4 sys/netinet6/in6.c:1037
in6_update_ifa(ffff800000d0b800,ffff800024b2f3f0,0) at in6_update_ifa+0x1418 in6_joingroup sys/netinet6/in6.c:1154 [inline]
in6_update_ifa(ffff800000d0b800,ffff800024b2f3f0,0) at in6_update_ifa+0x1418 sys/netinet6/in6.c:776
in6_ifattach_linklocal(ffff800000d0b800,0) at in6_ifattach_linklocal+0x28d sys/netinet6/in6_ifattach.c:281
in6_ifattach(ffff800000d0b800) at in6_ifattach+0x1bb sys/netinet6/in6_ifattach.c:405
ifnewlladdr(ffff800000d0b800) at ifnewlladdr+0x180 sys/net/if.c:3204
ifioctl(fffffd80641e53d8,8020691f,ffff800024b2f650,ffff8000211e8b40) at ifioctl+0x1f5e sys/net/if.c:2253
sys_ioctl(ffff8000211e8b40,ffff800024b2f768,ffff800024b2f7b0) at sys_ioctl+0x4a2
syscall(ffff800024b2f830) at syscall+0x606 mi_syscall sys/sys/syscall_mi.h:110 [inline]
syscall(ffff800024b2f830) at syscall+0x606 sys/arch/amd64/amd64/trap.c:625
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xb90fbeb3460, count: -9


---
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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.