syzbot


kernel: protection fault trap, code=0 (3)

Status: fixed on 2019/01/27 23:19
Reported-by: syzbot+c5997876fea393e6b948@syzkaller.appspotmail.com
Fix commit: Validate the user-supplied device index given to WSMUXIO_ADD_DEVICE. The same
First crash: 1972d, last: 1972d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd kernel: protection fault trap, code=0 (6) C 55024 1660d 1745d 3/3 fixed on 2019/12/05 05:48
openbsd kernel: protection fault trap, code=0 (4) C 759 1827d 1939d 3/3 fixed on 2019/06/22 17:44
openbsd kernel: protection fault trap, code=0 (8) syz 1348 1227d 1416d 3/3 fixed on 2021/02/10 20:48
openbsd kernel: protection fault trap, code=0 C 16 2026d 2030d 1/3 fixed on 2018/12/04 18:27
openbsd kernel: protection fault trap, code=0 (7) syz 774692 1416d 1660d 3/3 fixed on 2020/08/05 06:16
openbsd kernel: protection fault trap, code=0 (2) syz 109 1977d 2001d 3/3 fixed on 2019/01/22 07:18
openbsd kernel: protection fault trap, code=0 (5) C 607 1751d 1825d 3/3 fixed on 2019/09/05 13:34

Sample crash report:
login: kernel: protection fault trap, code=0
Stopped at      wsmux_getmux+0x247:     movq    0(%r12,%r15,8),%rbx
ddb> 
ddb> set $lines = 0
ddb> show panic
the kernel did not panic
ddb> trace
wsmux_getmux(b7d7f9c07d074208) at wsmux_getmux+0x247 sys/dev/wscons/wsmux.c:151
wsmux_do_ioctl(d15541cd434bc446,80085761,fffffd80355b2968,82,fffffd803f7c7ba0) at wsmux_do_ioctl+0x268 wsmux_add_mux sys/dev/wscons/wsmux.c:563 [inline]
wsmux_do_ioctl(d15541cd434bc446,80085761,fffffd80355b2968,82,fffffd803f7c7ba0) at wsmux_do_ioctl+0x268 sys/dev/wscons/wsmux.c:424
VOP_IOCTL(6c2539057c8d3560,80085761,fffffd80361c30f8,ffff80001496c718,fffffd80355b2968,ffff80001496c718) at VOP_IOCTL+0x80 sys/kern/vfs_vops.c:290
vn_ioctl(a3d07b2645faf15e,fffffd80361c30f8,ffff80001496c718,8) at vn_ioctl+0xc5 sys/kern/vfs_vnops.c:512sys_ioctl(47df970106db668d,2,ffff80001496c718) at sys_ioctl+0x639
syscall(53d665730488a663) at syscall+0x528
Xsyscall(6,0,7f7ffffc6548,0,1,7f7ffffc6558) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7ffffc64e0, count: -7
ddb> show registers
rdi                             0x40
rsi                       0xdf7ffce3
rbp               0xffff8000149a42e0
rbx                             0x40
rdx                             0x8b
rcx                              0x1
rax                                0
r8                0xffffffff81257b63    wsmux_do_ioctl+0x243
r9                               0x5
r10               0x74912713bbceea07
r11               0x616ad806869dc56c
r12               0xffff80000090e400
r13                             0x82
r14                       0xdf7ffce3
r15               0xffffffffdf7ffce3
rip               0xffffffff81258837    wsmux_getmux+0x247
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff8000149a4290
ss                              0x10
wsmux_getmux+0x247:     movq    0(%r12,%r15,8),%rbx
ddb> show proc
PROC (syz-executor7627) pid=140721 stat=onproc
    flags process=2<EXEC> proc=0
    pri=51, usrpri=51, nice=20
    forw=0xffffffffffffffff, list=0xffff80001496cbc8,0xffffffff822084f8
    process=0xffff8000ffff6358 user=0xffff80001499f000, vmspace=0xfffffd803f015738
    estcpu=1, cpticks=1, pctcpu=0.0
    user=0, sys=1, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
*92412  140721  52635      0  7         0x2                syz-executor7627
 52635  122267  29302      0  3    0x10008a  pause         ksh
 29302  380339  12914      0  3        0x92  select        sshd
 75225  271958      1      0  3    0x100083  ttyin         getty
 12914   54853      1      0  3        0x80  select        sshd
 69840  452209  58749     73  3    0x100090  kqread        syslogd
 58749  493267      1      0  3    0x100082  netio         syslogd
 78540  409985      1     77  3    0x100090  poll          dhclient
 85610  261204      1      0  3        0x80  poll          dhclient
  9208   99248      0      0  3     0x14200  pgzero        zerothread
  8730  349173      0      0  3     0x14200  aiodoned      aiodoned
 95369  371106      0      0  3     0x14200  syncer        update
 90651  104226      0      0  3     0x14200  cleaner       cleaner
 86722  286597      0      0  3     0x14200  reaper        reaper
 20484   32470      0      0  3     0x14200  pgdaemon      pagedaemon
 20632  131443      0      0  3     0x14200  bored         crynlk
 30823  412205      0      0  3     0x14200  bored         crypto
 28392  318641      0      0  3  0x40014200  acpi0         acpi0
 51058   12219      0      0  3     0x14200  bored         softnet
 57019  160550      0      0  3     0x14200  bored         systqmp
  6432  469524      0      0  3     0x14200  bored         systq
 39983   55061      0      0  3  0x40014200  bored         softclock
 52764    1157      0      0  3  0x40014200                idle0
     1  311832      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb> show all locks
No such command
ddb> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim Kern Lim
         devbuf  9427   6307K    6307K  78643K     10521        0        0
            pcb    23      9K       9K  78643K        55        0        0
         rtable    61      1K       2K  78643K       115        0        0
         ifaddr    21      7K       7K  78643K        21        0        0
       counters    19     16K      16K  78643K        19        0        0
       ioctlops     0      0K       2K  78643K        13        0        0
          mount     1      1K       1K  78643K         1        0        0
         vnodes  1167     73K      73K  78643K      1172        0        0
      UFS quota     1     32K      32K  78643K         1        0        0
      UFS mount     5     36K      36K  78643K         5        0        0
            shm     2      1K       1K  78643K         2        0        0
         VM map     2      0K       0K  78643K         2        0        0
            sem     2      0K       0K  78643K         2        0        0
        dirhash    12      2K       2K  78643K        12        0        0
           ACPI  1777    193K     286K  78643K     12501        0        0
      file desc     1      0K       0K  78643K         1        0        0
           proc    40     30K      38K  78643K       201        0        0
    NFS srvsock     1      0K       0K  78643K         1        0        0
     NFS daemon     1     16K      16K  78643K         1        0        0
       in_multi    11      0K       0K  78643K        11        0        0
    ether_multi     1      0K       0K  78643K         1        0        0
    ISOFS mount     1     32K      32K  78643K         1        0        0
  MSDOSFS mount     1     16K      16K  78643K         1        0        0
           ttys    18     79K      79K  78643K        18        0        0
           exec     0      0K       1K  78643K       149        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    47      2K       3K  78643K       665        0        0
       UVM aobj     2      2K       2K  78643K         2        0        0
        memdesc     1      4K       4K  78643K         1        0        0
    crypto data     1      1K       1K  78643K         1        0        0
            NDP     3      0K       0K  78643K         3        0        0
           temp    30   2327K    2391K  78643K      1690        0        0
      SYN cache     2     16K      16K  78643K         2        0        0
ddb> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
arp         64        2    0        0     1     0     1     1     0     8    0
inpcbpl    280       22    0       16     1     0     1     1     0     8    0
plimitpl   152       13    0        8     1     0     1     1     0     8    0
rtentry    112       23    0        1     1     0     1     1     0     8    0
syncache   264        5    0        5     2     1     1     1     0     8    1
tcpcb      544        8    0        5     1     0     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256       97    0        0     7     0     7     7     0     8    0
art_table   32       98    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
dino1pl    128     1383    0       17    45     0    45    45     0     8    0
ffsino     240     1383    0       17    81     0    81    81     0     8    0
nchpl      144     1554    0       30    57     0    57    57     0     8    0
uvmvnodes   72     1392    0        0    26     0    26    26     0     8    0
vnodes     200     1392    0        0    74     0    74    74     0     8    0
namei      1024    3257    0     3257     3     2     1     1     0     8    1
scxspl     192     2323    0     2323     6     1     5     5     0     8    5
sigapl     432      173    0      163     2     0     2     2     0     8    0
knotepl    112        5    0        0     1     0     1     1     0     8    0
kqueuepl   104        1    0        0     1     0     1     1     0     8    0
pipepl     112      114    0      107     3     2     1     1     0     8    0
fdescpl    424      174    0      163     2     0     2     2     0     8    0
filepl     120      808    0      765     2     0     2     2     0     8    0
lockfpl     96        7    0        6     2     1     1     1     0     8    0
lockfspl    24        4    0        3     2     1     1     1     0     8    0
sessionpl  112       17    0        9     1     0     1     1     0     8    0
pgrppl      48       17    0        9     1     0     1     1     0     8    0
ucredpl     96       47    0       40     1     0     1     1     0     8    0
zombiepl   144      163    0      163     3     2     1     1     0     8    1
processpl  840      187    0      163     4     1     3     4     0     8    0
procpl     600      187    0      163     3     0     3     3     0     8    0
sockpl     384       64    0       48     2     0     2     2     0     8    0
mcl4k      4096      10    0       10     2     1     1     1     0     8    1
mcl2k      2048    5507    0     5479     7     1     6     6     0     8    2
mtagpl      80        2    0        2     1     1     0     1     0     8    0
mbufpl     256     9553    0     9513     5     1     4     4     0     8    0
bufpl      256     1997    0      261   109     0   109   109     0     8    0
anonpl      16    17683    0    16589     8     2     6     7     0    62    1
amapchunkpl 152     553    0      518     2     0     2     2     0   158    0
amappl16   192       67    0       62     1     0     1     1     0     8    0
amappl15   184        1    0        0     1     0     1     1     0     8    0
amappl14   176        1    0        1     1     1     0     1     0     8    0
amappl13   168       15    0       12     1     0     1     1     0     8    0
amappl12   160        9    0        9     2     1     1     1     0     8    1
amappl11   152      176    0      167     1     0     1     1     0     8    0
amappl10   144       47    0       47     3     2     1     1     0     8    1
amappl9    136      192    0      191     1     0     1     1     0     8    0
amappl8    128      101    0       95     1     0     1     1     0     8    0
amappl7    120       28    0       24     1     0     1     1     0     8    0
amappl6    112       41    0       37     1     0     1     1     0     8    0
amappl5    104      158    0      147     1     0     1     1     0     8    0
amappl4     96      251    0      230     1     0     1     1     0     8    0
amappl3     88      111    0      106     1     0     1     1     0     8    0
amappl2     80      568    0      533     1     0     1     1     0     8    0
amappl1     72    11523    0    11134    16     7     9    16     0     8    0
amappl      72      381    0      362     1     0     1     1     0    75    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        1    0        0     1     0     1     1     0     8    0
uaddrrnd    24      174    0      163     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      174    0      163     1     0     1     1     0     8    0
vmmpekpl   168     5174    0     5160     1     0     1     1     0     8    0
vmmpepl    168    23357    0    22667    49    15    34    47     0   357    2
vmsppl     264      173    0      163     1     0     1     1     0     8    0
pdppl      4096     354    0      326     5     0     5     5     0     8    0
pvpl        32    70710    0    67990    35     9    26    26     0   265    3
pmappl     192      173    0      163     1     0     1     1     0     8    0
extentpl    40       39    0       25     1     0     1     1     0     8    0
phpool     112      226    0        7     7     0     7     7     0     8    0
ddb> 

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/01/27 06:34 openbsd fdee2cadce4b c73f090a .config console log report syz C ci-openbsd-main
2019/01/27 06:52 openbsd fdee2cadce4b c73f090a .config console log report ci-openbsd-main
2019/01/27 06:13 openbsd fdee2cadce4b c73f090a .config console log report ci-openbsd-main
* Struck through repros no longer work on HEAD.