syzbot


protection_fault: witness_checkorder (5)

Status: upstream: reported on 2025/02/06 12:35
Reported-by: syzbot+a61fbe87bc805c481c49@syzkaller.appspotmail.com
First crash: 176d, last: 20h59m
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd protection_fault: witness_checkorder (2) -1 C 311 633d 748d 0/3 auto-obsoleted due to no activity on 2023/12/28 01:55
openbsd protection_fault: witness_checkorder -1 1 1068d 1068d 0/3 auto-obsoleted due to no activity on 2022/11/27 19:38
openbsd protection_fault: witness_checkorder (4) -1 1 326d 326d 0/3 auto-obsoleted due to no activity on 2024/12/08 12:11
openbsd protection_fault: witness_checkorder (3) -1 1 515d 515d 0/3 auto-obsoleted due to no activity on 2024/06/02 14:39

Sample crash report:
kernel: protection fault trap, code=0
Stopped at      witness_checkorder+0xb5:        movl    0x20(%r14),%r15d
ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
the kernel did not panic
ddb{1}> trace
witness_checkorder(deadbeefdeadc017,9,0) at witness_checkorder+0xb5 sys/kern/subr_witness.c:779
mtx_enter(deadbeefdeadc007) at mtx_enter+0x4a sys/kern/kern_lock.c:260
prsignal(deadbeefdeadbeef,14) at prsignal+0x36 sys/kern/kern_sig.c:904
reaper(ffff8000ffffc2a0) at reaper+0x2cc sys/kern/kern_exit.c:516
end trace frame: 0x0, count: -4
ddb{1}> show registers
rdi                                0
rsi                                0
rbp               0xffff80002a278020
rbx                                0
rdx                                0
rcx               0xffff8000ffffc2a0
rax               0xffff8000299fdffe
r8                    0x7f7fffffc000
r9                               0x1
r10                0x33651f4e9fe7f6a
r11               0x6d881aa3132f7c80
r12               0xdeadbeefdeadbefe
r13                              0x9
r14               0xdeadbeefdeadc017
r15                                0
rip               0xffffffff82079745    witness_checkorder+0xb5
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff80002a277f80
ss                              0x10
witness_checkorder+0xb5:        movl    0x20(%r14),%r15d
ddb{1}> show proc
PROC (reaper) tid=183144 pid=51211 tcnt=1 stat=onproc
    flags process=14000<NOZOMBIE,SYSTEM> proc=200<SYSTEM>
    runpri=32, usrpri=50, slppri=32, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff8000ffffc538,0xffff8000ffffc018
    process=0xffff8000ffff49c8 user=0xffff80002a273000, vmspace=0xffffffff8386bc08
    estcpu=0, cpticks=3, pctcpu=0.0, user=0, sys=0, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 90786   27067  70240  32767  2        0x10                syz-executor
 28360  264248  44085  32767  2        0x10                syz-executor
 28360   26783  44085  32767  7   0x4000010                syz-executor
 88124  218079   9770  32767  2        0x10                syz-executor
 88124   30352   9770  32767  3   0x4000090  fsleep        syz-executor
 14197   80942  96158  32767  2        0x10                syz-executor
 14197  256221  96158  32767  3   0x4000090  fsleep        syz-executor
 44447  237384  76406      0  2    0x100000                sh
 54066  241328  25545      0  2    0x100000                sh
 25545  481702  63252      0  3    0x10008a  sigsusp       sh
 76406  515186  11002      0  3    0x10008a  sigsusp       sh
  9770  327597   6865  32767  2        0x10                syz-executor
 96158   63908  61217  32767  3        0x90  nanoslp       syz-executor
 63252  179761  86169      0  3        0x80  wait          syz-executor
 93019  439396  79620  32767  2  0x10000010                syz-executor
 71042  193756   1603  32767  2        0x10                syz-executor
 70240  102203  61061  32767  3        0x90  nanoslp       syz-executor
 11002  100334  13420      0  3        0x80  wait          syz-executor
 44085  482351  32274  32767  3        0x90  nanoslp       syz-executor
 61061  126426  88470      0  3        0x82  wait          syz-executor
  1603  318526  88470      0  3        0x82  wait          syz-executor
 61217   57132  88470      0  3        0x82  wait          syz-executor
 32274  359841  88470      0  3        0x82  wait          syz-executor
 13420  137376  88470      0  3        0x82  wait          syz-executor
  6865   90499  88470      0  3        0x82  wait          syz-executor
 86169  387001  88470      0  3        0x82  wait          syz-executor
 79620  264665  88470      0  3        0x82  wait          syz-executor
 88470  109058  43154      0  2         0x2                syz-executor
 43154  390045    176      0  3    0x10008a  sigsusp       ksh
   176  263494  81965      0  3        0x98  kqread        sshd-session
 81965  475269   6326      0  3        0x92  kqread        sshd-session
 12374   45405      1      0  3    0x100083  ttyin         getty
  6326  459438      1      0  3        0x88  kqread        sshd
 39327  438197  86299     73  3   0x1100090  kqread        syslogd
 86299  145237      1      0  3    0x100082  sbwait        syslogd
 69586  423375      1      0  3    0x100080  kqread        resolvd
 21899  475965  14266     77  3    0x100092  kqread        dhcpleased
 32952  272637  14266     77  3    0x100092  kqread        dhcpleased
 14266  230408      1      0  3        0x80  kqread        dhcpleased
 55753   60224      0      0  2  0x40014200                smr
 92897  519465      0      0  2     0x14200                zerothread
 85953  219608      0      0  3     0x14200  aiodoned      aiodoned
 56299  429795      0      0  3     0x14200  syncer        update
 48902  132788      0      0  3     0x14200  cleaner       cleaner
*51211  183144      0      0  7     0x14200                reaper
 75545  166977      0      0  3     0x14200  pgdaemon      pagedaemon
 32843  507809      0      0  3     0x14200  bored         viomb
 80893  499293      0      0  3  0x40014200  acpi0         acpi0
 74420  138027      0      0  3  0x40014200                idle1
 46900  365132      0      0  3     0x14200  bored         softnet7
 69308   57091      0      0  3     0x14200  bored         softnet6
  4254   22334      0      0  3     0x14200  bored         softnet5
 22312  505180      0      0  3     0x14200  bored         softnet4
 51101  178772      0      0  3     0x14200  bored         softnet3
 11254  138711      0      0  3     0x14200  bored         softnet2
 20329  207374      0      0  3     0x14200  bored         softnet1
 58663  143253      0      0  2     0x14200                softnet0
 80829  104343      0      0  3     0x14200  smrbar        systqmp
 37002  386224      0      0  3     0x14200  bored         systq
 46738  344544      0      0  3     0x14200  tmoslp        softclockmp
  7758  302582      0      0  3  0x40014200  tmoslp        softclock
 86789  491163      0      0  3  0x40014200                idle0
     1  349333      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
Process 51211 (reaper) thread 0xffff8000ffffc2a0 (183144)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff839227f8)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1
#2  sleep_finish+0x2d8 sys/kern/kern_synch.c:367
#3  rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298
#4  knote_processexit+0x2b sys/kern/kern_event.c:2217
#5  reaper+0x24d sys/kern/kern_exit.c:513
#6  proc_trampoline+0x10
Process 80829 (systqmp) thread 0xffff8000ffffe7c8 (104343)
shared rwlock systqmp r = 0 (0xffffffff8381d4e8)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  taskq_thread+0x12a sys/kern/kern_task.c:442
#2  proc_trampoline+0x10
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf 10186  10955K   10968K 166960K     11264        0
            pcb    17     12K      12K 166960K        17        0
         rtable   187      5K       5K 166960K       233        0
             pf    31     16K      16K 166960K        31        0
         ifaddr    39      6K       6K 166960K        41        0
        ifgroup    50      2K       2K 166960K        50        0
         sysctl     1      1K       9K 166960K         5        0
       counters    68     36K      36K 166960K        68        0
       ioctlops     0      0K       2K 166960K        28        0
            iov     0      0K       0K 166960K         1        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1334     84K      84K 166960K      1350        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     2      1K       1K 166960K         2        0
         VM map     2      1K       1K 166960K         2        0
            sem     2      0K       0K 166960K         2        0
        dirhash    12      2K       2K 166960K        12        0
           ACPI  1692    195K     286K 166960K     12470        0
      file desc    26     97K     121K 166960K       142        0
           proc    58     99K     163K 166960K       459        0
        subproc    72      4K       4K 166960K        72        0
    NFS srvsock     1      0K       0K 166960K         1        0
     NFS daemon     1     16K      16K 166960K         1        0
       in_multi    88      6K       6K 166960K        88        0
    ether_multi     1      0K       0K 166960K         1        0
    ISOFS mount     1     32K      32K 166960K         1        0
  MSDOSFS mount     1     16K      16K 166960K         1        0
           ttys    25    122K     122K 166960K        25        0
           exec     0      0K       1K 166960K       328        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   221    161K     167K 166960K      2725        0
       UVM aobj     3      2K       2K 166960K         3        0
     pinsyscall    47     94K     110K 166960K      1118        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
            NDP    25      1K       1K 166960K        25        0
           temp    33   8634K    8698K 166960K      3559        0
         kqueue    14     20K      20K 166960K        22        0
      SYN cache     2     16K      16K 166960K         2        0
ddb{1}> 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       30    0       27     1     0     1     1     0     8    0
rtentry    176       86    0        1     4     0     4     4     0     8    0
unpcb      144       34    0       19     1     0     1     1     0     8    0
syncache   336        3    0        3     1     0     1     1     0     8    1
tcpcb      736        7    0        3     1     0     1     1     0     8    0
arp        128        9    0        0     1     0     1     1     0     8    0
inpcb      328       53    0       46     1     0     1     1     0     8    0
nd6        144       14    0        0     1     0     1     1     0     8    0
kcovpl      48        8    0        0     1     0     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      395    0        0    25     0    25    25     0     8    0
art_table   40      396    0        0     4     0     4     4     0     8    0
art_node    32       86    0        4     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1546    0       45    94     0    94    94     0     8    0
ffsino     296     1546    0       45   116     0   116   116     0     8    0
nchpl      144     1731    0       58    63     0    63    63     0     8    0
uvmvnodes   80     1627    0        0    34     0    34    34     0     8    0
vnodes     216     1627    0        0    91     0    91    91     0     8    0
namei      1024    4991    0     4991     3     1     2     2     0     8    2
percpumem   16       49    0        0     1     0     1     1     0     8    0
kstatmem   264       24    0        0     2     0     2     2     0     8    0
scxspl     216     6275    0     6275     4     2     2     2     1     8    2
plimitpl   152       34    0       10     1     0     1     1     0     8    0
sigapl     424      417    0      356     8     0     8     8     0     8    0
knotepl    120       53    0        0     2     0     2     2     0     8    0
kqueuepl   224       18    0        8     1     0     1     1     0     8    0
pipepl     344       95    0       68     4     1     3     3     0     8    0
fdescpl    528      395    0      357     3     0     3     3     0     8    0
filepl     160     1248    0     1044     9     0     9     9     0     8    0
lockfpl    104        6    0        4     1     0     1     1     0     8    0
lockfspl    48        4    0        2     1     0     1     1     0     8    0
sessionpl  144       21    0        5     1     0     1     1     0     8    0
pgrppl      48       29    0        5     1     0     1     1     0     8    0
ucredpl    104       82    0       65     1     0     1     1     0     8    0
zombiepl   144      357    0      356     2     1     1     1     0     8    0
processpl  1248     417    0      356     7     1     6     6     0     8    0
procpl     664      426    0      362     6     0     6     6     0     8    0
sockpl     752      117    0       92     3     0     3     3     0     8    0
mcl8k      8192       2    0        0     1     0     1     1     0     8    0
mcl4k      4096     119    0        0    15     0    15    15     0     8    0
mcl2k      2048      17    0        0     3     0     3     3     0     8    0
mtagpl      96        3    0        0     1     0     1     1     0     8    0
mbufpl     256      148    0        0     9     0     9     9     0     8    0
bufpl      280     2803    0      116   192     0   192   192     0     8    0
anonpl      32     3640    0        0    30     0    30    30     0   246    0
amapchunkpl 152    7762    0     7315    23     4    19    19     0   158    1
amappl16   200     1534    0     1522     5     0     5     5     0     8    4
amappl15   192       11    0       11     2     1     1     1     0     8    1
amappl14   184       96    0       86     1     0     1     1     0     8    0
amappl13   176        3    0        3     1     0     1     1     0     8    1
amappl12   168      975    0      937     2     0     2     2     0     8    0
amappl11   160       43    0       33     1     0     1     1     0     8    0
amappl10   152       28    0       28     2     1     1     1     0     8    1
amappl9    144      237    0      236     1     0     1     1     0     8    0
amappl8    136       34    0       33     1     0     1     1     0     8    0
amappl7    128       92    0       82     1     0     1     1     0     8    0
amappl6    120      156    0      151     2     1     1     1     0     8    0
amappl5    112      171    0      165     1     0     1     1     0     8    0
amappl4    104      259    0      244     1     0     1     1     0     8    0
amappl3     96     1139    0     1036     3     0     3     3     0     8    0
amappl2     88      578    0      522     2     0     2     2     0     8    0
amappl1     80     7598    0     7022    14     0    14    14     0     8    1
amappl      88     2140    0     1985     4     0     4     4     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      395    0      357     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      395    0      357     1     0     1     1     0     8    0
vmmpekpl   168     4587    0     4555     2     0     2     2     0     8    0
vmmpepl    168    31155    0    29156    94     2    92    92     0   357    1
vmsppl     488      394    0      357     7     1     6     6     0     8    0
rwobjpl     80    12789    0    10344    53     0    53    53     0     8    0
pdppl      4096     798    0      714   108    12    96    96     0     8   12
pvpl        32     9432    0        0    77     1    76    76     0   265    0
pmappl     256      394    0      357     4     1     3     3     0     8    0
extentpl    40       45    0       27     1     0     1     1     0     8    0
phpool     112      271    0       16     8     0     8     8     0     8    0
ddb{1}> machine ddbcpu 0
Stopped at      x86_ipi_db+0x27:        addq    $0x8,%rsp
ddb{0}> trace
x86_ipi_db(ffffffff8379aff0) 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(ffffffff839225f0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline]
__mp_lock(ffffffff839225f0) at __mp_lock+0x192 sys/kern/kern_lock.c:165
vn_ioctl(fffffd806c503a28,80044b02,ffff800038441950,ffff800038037cb0) at vn_ioctl+0x4d sys/kern/vfs_vnops.c:514
sys_ioctl(ffff800038037cb0,ffff800038441b30,ffff800038441a80) at sys_ioctl+0x674 sys/kern/sys_generic.c:-1
syscall(ffff800038441b30) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff800038441b30) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x34fceff8aa0, count: -8
ddb{0}> machine ddbcpu 1
Stopped at      witness_checkorder+0xb5:        movl    0x20(%r14),%r15d
ddb{1}> trace
witness_checkorder(deadbeefdeadc017,9,0) at witness_checkorder+0xb5 sys/kern/subr_witness.c:779
mtx_enter(deadbeefdeadc007) at mtx_enter+0x4a sys/kern/kern_lock.c:260
prsignal(deadbeefdeadbeef,14) at prsignal+0x36 sys/kern/kern_sig.c:904
reaper(ffff8000ffffc2a0) at reaper+0x2cc sys/kern/kern_exit.c:516
end trace frame: 0x0, count: -4

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/01 13:31 openbsd 8693ef6a6ffe 3cda49cf .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/05/22 04:12 openbsd c902741cb17b 0919b50b .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/03/03 02:30 openbsd 2ca76a892c5e c3901742 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/02/11 06:35 openbsd c7df606a226b 43f51a00 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-multicore protection_fault: witness_checkorder
2025/02/07 14:11 openbsd 307723971475 a4f327c2 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-multicore protection_fault: witness_checkorder
2025/02/06 12:35 openbsd 4a7e1005694f 1e1faf27 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
* Struck through repros no longer work on HEAD.