syzbot


protection_fault: witness_checkorder (5)

Status: upstream: reported on 2025/02/06 12:35
Reported-by: syzbot+a61fbe87bc805c481c49@syzkaller.appspotmail.com
First crash: 483d, last: 34d
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 939d 1054d 0/3 auto-obsoleted due to no activity on 2023/12/28 01:55
openbsd protection_fault: witness_checkorder -1 1 1374d 1374d 0/3 auto-obsoleted due to no activity on 2022/11/27 19:38
openbsd protection_fault: witness_checkorder (4) -1 1 633d 633d 0/3 auto-obsoleted due to no activity on 2024/12/08 12:11
openbsd protection_fault: witness_checkorder (3) -1 1 821d 821d 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{0}> 
ddb{0}> set $lines = 0
ddb{0}> set $maxwidth = 0
ddb{0}> show panic
the kernel did not panic
ddb{0}> trace
witness_checkorder(deafbeaddeafbfc5,9,0) at witness_checkorder+0xb5 sys/kern/subr_witness.c:779
mtx_enter(deafbeaddeafbfb5) at mtx_enter+0x95 sys/kern/kern_lock.c:406
prsignal(deafbeaddeafbead,14) at prsignal+0x36 sys/kern/kern_sig.c:904
reaper(ffff8000ffffdc90) at reaper+0x2ec sys/kern/kern_exit.c:516
end trace frame: 0x0, count: -4
ddb{0}> show registers
rdi                                0
rsi                                0
rbp               0xffff80002a204d70
rbx                                0
rdx                                0
rcx               0xffff8000ffffdc90
rax               0xffffffff83922ffe    cpu_info_full_primary+0x1ffe
r8                    0x7f7fffffc000
r9                                 0
r10               0xf292c5782b718876
r11               0x7dbfba7fbde9376f
r12               0xdeafbeaddeafbffe
r13                              0x9
r14               0xdeafbeaddeafbfc5
r15                                0
rip               0xffffffff813866e5    witness_checkorder+0xb5
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff80002a204cd0
ss                              0x10
witness_checkorder+0xb5:        movl    0x20(%r14),%r15d
ddb{0}> show proc
PROC (reaper) tid=283301 pid=60916 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=0xffff8000fffff9f0,0xffff8000ffffd770
    process=0xffff8000ffffb9c0 user=0xffff80002a1ff000, vmspace=0xffffffff839c81e0
    estcpu=0, cpticks=17, pctcpu=0.0, user=0, sys=0, intr=0
ddb{0}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 68980  421760  57746  32767  4     0x82010                syz-executor
 68980  463387  57746  32767  2   0x4002010                syz-executor
 68980  220950  57746  32767  4   0x4082010                syz-executor
 10945  347883  56649  32767  2        0x10                syz-executor
 10945  318521  56649  32767  3   0x4000090  fsleep        syz-executor
 51097  397587  48078  32767  2        0x10                syz-executor
 51097  267195  48078  32767  7   0x4000010                syz-executor
 51097   14659  48078  32767  3   0x4000090  fsleep        syz-executor
 52698  203788  57408  32767  2        0x10                syz-executor
 52698  257617  57408  32767  3   0x4000090  fsleep        syz-executor
 57408  201689  15595  32767  3        0x90  nanoslp       syz-executor
 57746  408141   7671  32767  3        0x90  nanoslp       syz-executor
 36083  120309  33397  32767  3        0x90  nanoslp       syz-executor
 56649  338821  51559  32767  3        0x90  nanoslp       syz-executor
  8600   60533  58172  32767  3        0x90  nanoslp       syz-executor
 54681  221898  53908  32767  2        0x10                syz-executor
 48078  467093  43313  32767  3        0x90  nanoslp       syz-executor
 15595  484714      1      0  3        0x82  wait          syz-executor
 33397  414218      1      0  3        0x82  wait          syz-executor
  7671  379765      1      0  3        0x82  wait          syz-executor
 51559   91110      1      0  3        0x82  wait          syz-executor
 58172  508306      1      0  3        0x82  wait          syz-executor
 53908  347240      1      0  3        0x82  wait          syz-executor
 43313  222933      1      0  3        0x82  wait          syz-executor
 62387  121002  69237      0  3    0x10008a  sigsusp       ksh
 69237  357826  26235      0  3        0x98  kqread        sshd-session
 26235   68829  16464      0  3        0x92  kqread        sshd-session
 62682  218414      1      0  3    0x100083  ttyin         getty
 16464  109931      1      0  3        0x88  kqread        sshd
 13358  374856  93123     73  3   0x1100090  kqread        syslogd
 93123  413386      1      0  3    0x100082  sbwait        syslogd
 13279  267629      1      0  3    0x100080  kqread        resolvd
 97671   85998  85549     77  3    0x100092  kqread        dhcpleased
 61524  357119  85549     77  3    0x100092  kqread        dhcpleased
 85549  362525      1      0  3        0x80  kqread        dhcpleased
  7719  395011      0      0  3     0x14200  bored         smr
 87593  481722      0      0  2     0x14200                zerothread
 10897   34901      0      0  3     0x14200  aiodoned      aiodoned
 66588   87184      0      0  3     0x14200  syncer        update
 43161   81066      0      0  3     0x14200  cleaner       cleaner
*60916  283301      0      0  7     0x14200                reaper
 21254  499680      0      0  3     0x14200  pgdaemon      pagedaemon
  9780  307432      0      0  3     0x14200  bored         viomb
 78368  271718      0      0  3  0x40014200  acpi0         acpi0
 63319  348144      0      0  3  0x40014200                idle1
 32612  446200      0      0  3     0x14200  bored         softnet1
  3641  407915      0      0  2     0x14200                softnet0
 20057  276096      0      0  3     0x14200  bored         systqmp
 77381  282355      0      0  3     0x14200  bored         systq
  6461  295887      0      0  3     0x14200  tmoslp        softclockmp
 73458  333096      0      0  3  0x40014200  tmoslp        softclock
 32781   53136      0      0  3  0x40014200                idle0
     1  391608      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{0}> show all locks
Process 51097 (syz-executor) thread 0xffff8000fffe74e0 (267195)
shared rwlock vmmaplk r = 0 (0xfffffd806c82be80)
#0  witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
#0  witness_lock+0x5f1 sys/kern/subr_witness.c:1160
#1  rw_do_enter_read+0x3e8 sys/kern/kern_rwlock.c:413
#2  uvmfault_lookup+0x122 sys/uvm/uvm_fault.c:1880
Process 60916 (reaper) thread 0xffff8000ffffdc90 (283301)
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff839cac80)
#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:369
#3  rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298
#4  knote_processexit+0x2b sys/kern/kern_event.c:2217
#5  reaper+0x26d sys/kern/kern_exit.c:513
#6  proc_trampoline+0x10
ddb{0}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf 11050  12016K   12034K 166960K     12144        0
            pcb    17     12K      12K 166960K        17        0
         rtable   215      6K       7K 166960K       486        0
             pf    29     16K      16K 166960K        31        0
         ifaddr    38      6K       7K 166960K        44        0
        ifgroup    46      2K       2K 166960K        50        0
         sysctl     3      1K       9K 166960K         8        0
       counters    68     36K      37K 166960K        70        0
       ioctlops     0      0K       2K 166960K       103        0
            iov     0      0K      16K 166960K       160        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1288     81K      81K 166960K      1562        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     2      1K       5K 166960K        12        0
         VM map     2      1K       1K 166960K         2        0
            sem    12      1K       1K 166960K        30        0
        dirhash    12      2K       2K 166960K        18        0
           ACPI  1692    195K     286K 166960K     12470        0
      file desc    19     72K     129K 166960K       500        0
          sigio     0      0K       0K 166960K         8        0
           proc    58     99K     163K 166960K       535        0
        subproc    63      3K       4K 166960K       261        0
    NFS srvsock     1      0K       0K 166960K         1        0
     NFS daemon     1     16K      16K 166960K         1        0
    ip_moptions     0      0K       0K 166960K       207        0
       in_multi    88      6K       7K 166960K       114        0
    ether_multi     1      0K       0K 166960K         2        0
            mrt     1      0K       0K 166960K        17        0
    ISOFS mount     1     32K      32K 166960K         1        0
  MSDOSFS mount     1     16K      16K 166960K         1        0
           ttys    61    281K     281K 166960K        61        0
           exec     0      0K       1K 166960K       411        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   209    143K     177K 166960K      5940        0
       UVM aobj    24      2K       2K 166960K        24        0
     pinsyscall    40     80K     113K 166960K      1584        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
    ip6_options     0      0K       0K 166960K        36        0
            NDP    10      0K       2K 166960K        27        0
           temp    40   9072K    9136K 166960K      5439        0
         kqueue    14     20K      24K 166960K        67        0
      SYN cache     2     16K      16K 166960K         2        0
ddb{0}> 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       49    0       46     1     0     1     1     0     8    0
rtentry    176      113    0       14     6     1     5     6     0     8    0
unpcb      144      481    0      466     4     3     1     4     0     8    0
syncache   336       14    0       14     1     0     1     1     0     8    1
tcpcb      736      235    0      230     7     6     1     7     0     8    0
arp        136       18    0        2     1     0     1     1     0     8    0
ipq         40        2    0        0     1     0     1     1     0     8    0
ipqe        40       68    0       64     1     0     1     1     0     8    0
inpcb      328      491    0      483    10     3     7     7     0     8    6
ip6q        72        3    0        0     1     0     1     1     0     8    0
ip6af       40        4    0        1     1     0     1     1     0     8    0
nd6        152       26    0        5     1     0     1     1     0     8    0
kcovpl      48       29    0       22     1     0     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      456    0       48    29     1    28    29     0     8    0
art_table   40      457    0       48     5     0     5     5     0     8    0
art_node    32      113    0       23     1     0     1     1     0     8    0
sysvmsgpl   40        3    0        1     1     0     1     1     0     8    0
semapl     112       26    0       16     1     0     1     1     0     8    0
shmpl      112       21    0        0     1     0     1     1     0     8    0
dirhash    1024      21    0        4     3     0     3     3     0     8    0
dino2pl    256     1975    0      491    94     0    94    94     0     8    0
ffsino     296     1975    0      491   115     0   115   115     0     8    0
nchpl      144     2551    0      836    64     0    64    64     0     8    0
vnodes     216     2245    0        0   125     0   125   125     0     8    0
namei      1024    8291    0     8291     1     0     1     1     0     8    1
percpumem   16       50    0        1     1     0     1     1     0     8    0
kstatmem   264       25    0        2     2     0     2     2     0     8    0
scxspl     216     8768    0     8768    11     3     8     8     1     8    8
plimitpl   152      185    0      161     3     2     1     2     0     8    0
sigapl     424      749    0      699     7     0     7     7     0     8    0
knotepl    120      335    0        0    10     0    10    10     0     8    0
kqueuepl   224       83    0       74     1     0     1     1     0     8    0
pipepl     344      206    0      182     3     0     3     3     0     8    0
fdescpl    528      733    0      702     4     1     3     4     0     8    0
filepl     160     3864    0     3702    14     2    12    12     0     8    3
lockfpl    104      102    0      100     1     0     1     1     0     8    0
lockfspl    48       34    0       32     1     0     1     1     0     8    0
sessionpl  144       66    0       51     1     0     1     1     0     8    0
pgrppl      48       99    0       77     1     0     1     1     0     8    0
ucredpl    104      525    0      507     1     0     1     1     0     8    0
zombiepl   144      702    0      699     1     0     1     1     0     8    0
processpl  1232     749    0      699     5     0     5     5     0     8    0
procpl     664     1250    0     1192     7     1     6     7     0     8    0
sosppl     176        1    0        1     1     0     1     1     0     8    1
sockpl     752     1025    0      999    15     5    10    11     0     8    7
mcl64k     65536      3    0        0     1     0     1     1     0     8    0
mcl16k     16384      2    0        0     1     0     1     1     0     8    0
mcl12k     12288      1    0        0     1     0     1     1     0     8    0
mcl9k128   9344       1    0        0     1     0     1     1     0     8    0
mcl8k      8192       2    0        0     1     0     1     1     0     8    0
mcl4k      4096     112    0        0    14     0    14    14     0     8    0
mcl2k2     2112       1    0        0     1     0     1     1     0     8    0
mcl2k      2048      21    0        0     3     0     3     3     0     8    0
mtagpl      96        3    0        0     1     0     1     1     0     8    0
mbufpl     256      297    0        0    19     0    19    19     0     8    0
bufpl      280     2892    0      108   199     0   199   199     0     8    0
anonpl      32     6864    0        0    56     0    56    56     0   246    0
amapchunkpl 152   18235    0    17811    29     3    26    27     0   158    5
amappl16   200     2496    0     2470    13    11     2    11     0     8    0
amappl15   192        8    0        8     1     1     0     1     0     8    0
amappl14   184      402    0      401     1     0     1     1     0     8    0
amappl13   176      121    0      111     1     0     1     1     0     8    0
amappl12   168      966    0      936     2     0     2     2     0     8    0
amappl11   160        1    0        1     1     1     0     1     0     8    0
amappl10   152       60    0       50     1     0     1     1     0     8    0
amappl9    144      257    0      257     1     1     0     1     0     8    0
amappl8    136       99    0       98     1     0     1     1     0     8    0
amappl7    128      140    0      129     1     0     1     1     0     8    0
amappl6    120      165    0      163     1     0     1     1     0     8    0
amappl5    112      100    0       93     1     0     1     1     0     8    0
amappl4    104      268    0      253     1     0     1     1     0     8    0
amappl3     96     3382    0     3280     5     1     4     4     0     8    0
amappl2     88      532    0      483     2     0     2     2     0     8    0
amappl1     80    11580    0    11031    19     3    16    16     0     8    2
amappl      88     5177    0     5030     5     0     5     5     0    92    0
uvmvnodes   80      106    0        0     3     0     3     3     0     8    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       23    0        0     1     0     1     1     0     8    0
uaddrrnd    24      733    0      702     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      733    0      702     1     0     1     1     0     8    0
vmmpekpl   168     8132    0     8088     3     0     3     3     0     8    0
vmmpepl    168    55514    0    53744   105     8    97   103     0   357   11
vmsppl     488      732    0      699     7     2     5     6     0     8    0
rwobjpl     80    18402    0    17495    27     3    24    25     0     8    2
pdppl      4096    1473    0     1398   137    56    81    99     0     8    6
pvpl        32    12875    0        0   104     0   104   104     0   265    0
pmappl     256      732    0      699     4     1     3     3     0     8    0
extentpl    40       45    0       27     1     0     1     1     0     8    0
phpool     112      319    0       66     8     0     8     8     0     8    0
ddb{0}> machine ddbcpu 0
Invalid cpu 0
ddb{0}> trace
witness_checkorder(deafbeaddeafbfc5,9,0) at witness_checkorder+0xb5 sys/kern/subr_witness.c:779
mtx_enter(deafbeaddeafbfb5) at mtx_enter+0x95 sys/kern/kern_lock.c:406
prsignal(deafbeaddeafbead,14) at prsignal+0x36 sys/kern/kern_sig.c:904
reaper(ffff8000ffffdc90) at reaper+0x2ec sys/kern/kern_exit.c:516
end trace frame: 0x0, count: -4
ddb{0}> machine ddbcpu 1
Stopped at      x86_ipi_db+0x27:        addq    $0x8,%rsp
ddb{1}> trace
x86_ipi_db(ffff8000299adff0) 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
__sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x18 kd_curproc sys/dev/kcov.c:580 [inline]
__sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x18 sys/dev/kcov.c:153
witness_lock(fffffd806c82be80,1) at witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline]
witness_lock(fffffd806c82be80,1) at witness_lock+0x5f1 sys/kern/subr_witness.c:1160
rw_do_enter_read(fffffd806c82be68,0) at rw_do_enter_read+0x3e8 sys/kern/kern_rwlock.c:413
uvmfault_lookup(ffff80002ffd22f0,0) at uvmfault_lookup+0x122 sys/uvm/uvm_fault.c:1880
uvm_fault_check(ffff80002ffd22f0,ffff80002ffd2328,ffff80002ffd2360,0) at uvm_fault_check+0x4f sys/uvm/uvm_fault.c:693
uvm_fault(fffffd806c82bd80,57000,0,2) at uvm_fault+0x106 sys/uvm/uvm_fault.c:627
kpageflttrap(ffff80002ffd24a0,57960) at kpageflttrap+0x2f4 sys/arch/amd64/amd64/trap.c:283
kerntrap(ffff80002ffd24a0) at kerntrap+0x19d sys/arch/amd64/amd64/trap.c:528
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
copyout() at copyout+0x64
syscall(ffff80002ffd28e0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002ffd28e0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x2d1402a3c40, count: -15

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/01 10:39 openbsd d15801fa3705 340bcdf0 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2026/04/08 02:04 openbsd 008d3704691e 4b3d9a38 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2026/03/21 12:05 openbsd a71bcab410b6 5b92003d .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2026/01/22 21:14 openbsd 9e4d3748fbc0 56f88057 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2026/01/11 22:59 openbsd 527652508a36 56f88057 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2026/01/03 02:33 openbsd 287000ffa12f e3fbc05e .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/12/17 06:33 openbsd 3a6d4b98bde9 a066d2bc .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-multicore protection_fault: witness_checkorder
2025/12/16 04:47 openbsd e03bf016d023 a066d2bc .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/11/20 04:55 openbsd 9c1a3717ded9 26ee5237 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/11/10 19:53 openbsd d046e1d8fd3f 4e1406b4 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/11/07 12:00 openbsd e6704d8803de 4e1406b4 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/11/05 13:07 openbsd 69af9e93ff65 a6c9c731 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/11/02 14:16 openbsd 6e779084bd79 2c50b6a9 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
2025/08/14 02:11 openbsd f6ad99933bf1 22ec1469 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-setuid protection_fault: witness_checkorder
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.