syzbot


protection_fault: pf_anchor_global_RB_REMOVE (3)

Status: upstream: reported on 2026/03/28 06:46
Reported-by: syzbot+839c1d9df91ce3820b90@syzkaller.appspotmail.com
First crash: 17d, last: 1d07h
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd protection_fault: pf_anchor_global_RB_REMOVE -1 73 1426d 1513d 3/3 fixed on 2022/06/27 02:23
openbsd protection_fault: pf_anchor_global_RB_REMOVE (2) -1 5 139d 286d 0/3 auto-obsoleted due to no activity on 2026/02/24 00:50

Sample crash report:
kernel: protection fault trap, code=0
Stopped at      pf_anchor_global_RB_REMOVE+0x81:        movq    0(%r12),%r15
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
the kernel did not panic
ddb> trace
pf_anchor_global_RB_REMOVE(ffffffff83a42cb8,ffff80000167f250) at pf_anchor_global_RB_REMOVE+0x81 sys/net/pf_ruleset.c:82
pf_remove_if_empty_ruleset(ffff80000167f6e0) at pf_remove_if_empty_ruleset+0x12d sys/net/pf_ruleset.c:301
pfi_dynaddr_setup(ffff80000164d7f8,0,1) at pfi_dynaddr_setup+0x671 sys/net/pf_if.c:508
pf_addr_setup(ffffffff83a43150,ffff80000164d7f8,0) at pf_addr_setup+0x46 sys/net/pf_ioctl.c:948
pfioctl(14900,cd60441a,ffff8000015dc000,83,ffff80003c90bca8) at pfioctl+0x9aee sys/net/pf_ioctl.c:2653
VOP_IOCTL(fffffd806c5ee208,cd60441a,ffff8000015dc000,83,fffffd8007ffd7b8,ffff80003c90bca8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd806b1c6db0,cd60441a,ffff8000015dc000,ffff80003c90bca8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:537
sys_ioctl(ffff80003c90bca8,ffff80002f0c1da0,ffff80002f0c1cf0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1
syscall(ffff80002f0c1da0) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002f0c1da0) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x86df37dd50, count: -10
ddb> show registers
rdi               0xffff800033cce000
rsi                            0xc3b
rbp               0xffff80002f0c1770
rbx               0xffffffff83a42cb8    pf_anchors
rdx               0xffff800033cce000
rcx                            0xc3a
rax               0xffffffff83039c7f    pf_anchor_global_RB_REMOVE+0x2f
r8                             0x3fc
r9                0x8080808080808080
r10                0x797da8775b79a85
r11               0xbd706b5604e08929
r12               0xf68eaffd597cb7bc
r13                              0x1
r14               0xffff80000167f250
r15               0x3919ab04b8efe172
rip               0xffffffff83039cd1    pf_anchor_global_RB_REMOVE+0x81
cs                               0x8
rflags                       0x10282    __ALIGN_SIZE+0xf282
rsp               0xffff80002f0c1720
ss                              0x10
pf_anchor_global_RB_REMOVE+0x81:        movq    0(%r12),%r15
ddb> show proc
PROC (syz-executor) tid=308628 pid=63553 tcnt=3 stat=onproc
    flags process=0 proc=4000000<THREAD>
    runpri=32, usrpri=86, slppri=32, nice=20
    wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
    forw=0xffffffffffffffff, list=0xffff80002a76a7e0,0xffff80002a76bcb0
    process=0xffff8000ffffb198 user=0xffff80002f0bc000, vmspace=0xfffffd806cb1bb90
    estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 49552  266974  14333      0  2           0                syz-executor
 49552  379854  14333      0  3   0x4000080  fsleep        syz-executor
 63553  406236  81446      0  2           0                syz-executor
 63553  441945  81446      0  3   0x4000080  kqpoll        syz-executor
*63553  308628  81446      0  7   0x4000000                syz-executor
 14382  299637  57428      0  3        0x80  nanoslp       syz-executor
 14382  320170  57428      0  3   0x4000080  pipewr        syz-executor
 14382  506910  57428      0  3   0x4000080  fsleep        syz-executor
 14382  447325  57428      0  3   0x4000080  fsleep        syz-executor
 86008  322033  90911      0  2       0xc80                syz-executor
 86008    1294  90911      0  3   0x4000080  kqread        syz-executor
 86008  457615  90911      0  3   0x4000080  sbwait        syz-executor
 86008  325901  90911      0  3   0x4000080  fsleep        syz-executor
 22706  435510  12793      0  3        0x80  nanoslp       syz-executor
 22706  415930  12793      0  3   0x4000080  sbwait        syz-executor
 22706  397856  12793      0  3   0x4000080  fsleep        syz-executor
 79290  519516      0      0  3     0x14280  nfsidl        nfsio
 43566  414881      0      0  3     0x14280  nfsidl        nfsio
 76589  511899      0      0  3     0x14280  nfsidl        nfsio
 31285  130645      0      0  3     0x14280  nfsidl        nfsio
 71622  343731      0      0  3     0x14280  nfsidl        nfsio
 81532  247997      0      0  3     0x14280  nfsidl        nfsio
 24014  498454      0      0  3     0x14280  nfsidl        nfsio
 95099  137310      0      0  3     0x14280  nfsidl        nfsio
 24774  207760      0      0  3     0x14280  nfsidl        nfsio
 68097   34050      0      0  3     0x14280  nfsidl        nfsio
 13702  229757      0      0  3     0x14280  nfsidl        nfsio
 91560  313053      0      0  3     0x14280  nfsidl        nfsio
 85651  365177      0      0  3     0x14280  nfsidl        nfsio
 60840  231683      0      0  3     0x14280  nfsidl        nfsio
 56419  104864      0      0  3     0x14280  nfsidl        nfsio
 84386  236316      0      0  3     0x14280  nfsidl        nfsio
 47834   85145      0      0  3     0x14280  nfsidl        nfsio
 18947   31153      0      0  3     0x14280  nfsidl        nfsio
 77859  193994      0      0  3     0x14280  nfsidl        nfsio
 55202  125588      0      0  3     0x14280  nfsidl        nfsio
 14333  471167  16193      0  2       0xc82                syz-executor
 49501  518155  16193      0  2         0x2                syz-executor
 57428   29874  16193      0  2       0xc82                syz-executor
 81446  136096  16193      0  3        0x82  nanoslp       syz-executor
 53692  240705  16193      0  2         0x2                syz-executor
 90911  212325  16193      0  3        0x82  nanoslp       syz-executor
 20931  179466  16193      0  3        0x82  wait          syz-executor
 12793  172740  16193      0  2       0xc82                syz-executor
 16193  116137  71077      0  3        0x82  kqread        syz-executor
 71077  496532  52258      0  3    0x10008a  sigsusp       ksh
 52258  193074  45957      0  3        0x98  kqread        sshd-session
 45957  227734  74564      0  3        0x92  kqread        sshd-session
 13262  403563      1      0  3    0x100083  ttyin         getty
 74564   87312      1      0  3        0x88  kqread        sshd
 20846   42840  28246     73  3   0x1100090  kqread        syslogd
 28246  348761      1      0  3    0x100082  sbwait        syslogd
 74001  266476      1      0  3    0x100080  kqread        resolvd
 94001  246452   6029     77  3    0x100092  kqread        dhcpleased
 55107   57124   6029     77  3    0x100092  kqread        dhcpleased
  6029   39501      1      0  3        0x80  kqread        dhcpleased
  9561  257663      0      0  2     0x14200                smr
  2551   36486      0      0  2     0x14200                zerothread
 64640  475379      0      0  3     0x14200  aiodoned      aiodoned
 36327  306435      0      0  3     0x14200  syncer        update
 25906  417475      0      0  3     0x14200  cleaner       cleaner
 73272  165128      0      0  3     0x14200  reaper        reaper
 67516  116139      0      0  3     0x14200  pgdaemon      pagedaemon
 45179  304574      0      0  3     0x14200  bored         viomb
 19105  391932      0      0  3  0x40014200  acpi0         acpi0
 86176  369037      0      0  3     0x14200  bored         softnet0
 15014  257627      0      0  3     0x14200  bored         systqmp
 93856  200001      0      0  3     0x14200  bored         systq
 63022  244186      0      0  2  0x40014200                softclock
  6447  335045      0      0  3  0x40014200                idle0
     1  160891      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
         devbuf 11041  12106K   12365K 166960K     12378        0
            pcb    17     14K      15K 166960K        67        0
         rtable   215      6K       7K 166960K       368        0
             pf    32     13K      16K 166960K        63        0
         ifaddr    37      6K       7K 166960K        55        0
        ifgroup    46      2K       2K 166960K        77        0
         sysctl     3      1K       9K 166960K         9        0
       counters    32     17K      18K 166960K        44        0
       ioctlops     1      4K       4K 166960K       135        0
            iov     1     12K      24K 166960K         8        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1327     83K      84K 166960K      1540        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     2      1K       5K 166960K         3        0
         VM map     2      1K       1K 166960K         2        0
            sem    12      0K       0K 166960K        43        0
        dirhash    12      2K       2K 166960K        12        0
           ACPI  1692    195K     286K 166960K     12470        0
      file desc    16     57K      97K 166960K       316        0
          sigio     0      0K       0K 166960K         1        0
           proc    60     59K     124K 166960K       514        0
        subproc    72      4K       4K 166960K        72        0
    NFS srvsock     1      0K       0K 166960K         1        0
     NFS daemon     1     16K      16K 166960K         1        0
    ip_moptions     0      0K       0K 166960K        11        0
       in_multi    87      6K       7K 166960K       101        0
    ether_multi     1      0K       0K 166960K         1        0
            mrt     0      0K       0K 166960K         8        0
    ISOFS mount     1     32K      32K 166960K         1        0
  MSDOSFS mount     1     16K      16K 166960K         1        0
           ttys    79    360K     360K 166960K        79        0
           exec     0      0K       1K 166960K       385        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   225    159K     174K 166960K      4522        0
       UVM aobj     5      2K       2K 166960K         5        0
     pinsyscall    37     74K      96K 166960K      1407        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
    ip6_options     0      0K       0K 166960K        14        0
            NDP    10      0K       2K 166960K        35        0
           temp    43   9067K    9132K 166960K     10230        0
         kqueue    16     24K      26K 166960K        61        0
      SYN cache     2     16K      16K 166960K         2        0
ddb> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
rtpcb      120       47    0       44     1     0     1     1     0     8    0
rtentry    136      115    0       17     4     0     4     4     0     8    0
unpcb      144      260    0      242     6     0     6     6     0     8    5
syncache   336        3    0        3     1     1     0     1     0     8    0
tcpcb      736       61    0       56     2     0     2     2     0     8    1
arp         96       18    0        4     1     0     1     1     0     8    0
ipq         40        3    0        2     2     1     1     1     0     8    0
ipqe        40        6    0        5     2     1     1     1     0     8    0
inpcb      328      270    0      262     7     0     7     7     0     8    5
nd6        112       27    0        3     1     0     1     1     0     8    0
pkpcb       40        1    0        0     1     0     1     1     0     8    0
kcovpl      48        8    0        0     1     0     1     1     0     8    0
ppxss      1072       7    0        7     1     0     1     1     0     8    1
pppxif     1416       1    0        1     1     0     1     1     0     8    1
pfrktable  1344       1    1        1     1     0     1     1     0     8    1
pfanchor   1288       1    0        1     1     0     1     1     0     8    1
pfrule     1360       5    0        4     2     1     1     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      464    0       54    29     0    29    29     0     8    1
art_table   40      465    0       54     5     0     5     5     0     8    0
art_node    32      115    0       26     1     0     1     1     0     8    0
sysvmsgpl   40        7    0        5     1     0     1     1     0     8    0
semupl     112        1    0        1     1     0     1     1     0     8    1
semapl     112       40    0       30     1     0     1     1     0     8    0
shmpl      112        2    0        0     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1898    0      447    92     0    92    92     0     8    0
ffsino     256     1898    0      447    92     0    92    92     0     8    0
nchpl      144     2351    0      658    64     0    64    64     0     8    0
vnodes     216     2098    0        0   117     0   117   117     0     8    0
namei      1024    7097    0     7096     3     2     1     2     0     8    0
pfiaddrpl  120        1    0        0     1     0     1     1     0     8    0
kstatmem   264       38    0       18     2     0     2     2     0     8    0
scsiplug    72        3    0        3     1     0     1     1     0     8    1
scxspl     216     7777    0     7777     4     2     2     3     1     8    2
plimitpl   152       45    0       28     1     0     1     1     0     8    0
sigapl     424      629    0      568     9     1     8     8     0     8    0
knotepl    120    19538    0    19485    11     1    10    11     0     8    8
kqueuepl   184       81    0       68     1     0     1     1     0     8    0
pipepl     304      134    0      106     3     0     3     3     0     8    0
fdescpl    448      596    0      568     5     1     4     5     0     8    0
filepl     120     2824    0     2604    13     0    13    13     0     8    5
lockfpl    104       79    0       76     1     0     1     1     0     8    0
lockfspl    48       35    0       32     1     0     1     1     0     8    0
sessionpl  144       59    0       51     1     0     1     1     0     8    0
pgrppl      48       69    0       53     1     0     1     1     0     8    0
ucredpl    104      313    0      302     1     0     1     1     0     8    0
zombiepl   144      569    0      568     1     0     1     1     0     8    0
processpl  1152     629    0      568     5     0     5     5     0     8    0
procpl     664      903    0      831     7     0     7     7     0     8    0
sockpl     552      586    0      556    17     0    17    17     0     8   14
mcl64k     65536     17    0       17     2     1     1     1     0     8    1
mcl16k     16384      2    0        2     1     1     0     1     0     8    0
mcl9k      9216       1    0        1     1     0     1     1     0     8    1
mcl8k      8192       8    0        8     2     1     1     1     0     8    1
mcl4k      4096    2716    0     2664    13     5     8    12     0     8    1
mcl2k      2048     269    0      267     1     0     1     1     0     8    0
mtagpl      96        7    0        6     1     0     1     1     0     8    0
mbufpl     256     5725    0     5570    13     1    12    12     0     8    1
bufpl      280     2612    0      103   180     0   180   180     0     8    0
anonpl      24   122327    0   119065    45     0    45    45     0   187   16
amapchunkpl 152   13848    0    13381    33     1    32    32     0   158   11
amappl16   200     2418    0     2392    17     6    11    14     0     8    8
amappl15   192       11    0       11     1     1     0     1     0     8    0
amappl14   184      416    0      415     1     0     1     1     0     8    0
amappl13   176      110    0      100     1     0     1     1     0     8    0
amappl12   168      854    0      827     2     0     2     2     0     8    0
amappl11   160        5    0        5     1     1     0     1     0     8    0
amappl10   152       89    0       79     1     0     1     1     0     8    0
amappl9    144      258    0      258     1     1     0     1     0     8    0
amappl8    136       97    0       95     1     0     1     1     0     8    0
amappl7    128      141    0      130     1     0     1     1     0     8    0
amappl6    120      150    0      148     1     0     1     1     0     8    0
amappl5    112       91    0       84     1     0     1     1     0     8    0
amappl4    104      258    0      240     1     0     1     1     0     8    0
amappl3     96     2560    0     2456     3     0     3     3     0     8    0
amappl2     88      505    0      449     2     0     2     2     0     8    0
amappl1     80     9831    0     9275    14     2    12    14     0     8    0
amappl      88     3800    0     3639     5     0     5     5     0    92    1
uvmvnodes   80      102    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
dma512     512        1    0        1     1     1     0     1     0     8    0
dma256     256        6    0        6     1     1     0     1     0     8    0
dma128     128      254    0      254     2     1     1     1     0     8    1
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        4    0        0     1     0     1     1     0     8    0
uaddrrnd    24      596    0      568     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      596    0      568     1     0     1     1     0     8    0
vmmpekpl   168     6308    0     6266     3     0     3     3     0     8    0
vmmpepl    168    45907    0    44171    92     1    91    91     0   357   10
vmsppl     368      595    0      568     4     1     3     4     0     8    0
rwobjpl     40    15621    0    14662    13     0    13    13     0     8    1
pdppl      4096    1198    0     1136   102    36    66    82     0     8    4
pvpl        32   292337    0   283886   111     5   106   106     0   265   16
pmappl     216      595    0      568     3     0     3     3     0     8    0
extentpl    40       45    0       27     1     0     1     1     0     8    0
phpool     112      372    0       54    10     0    10    10     0     8    0
ddb> machine ddbcpu 0
No such command
ddb> trace
pf_anchor_global_RB_REMOVE(ffffffff83a42cb8,ffff80000167f250) at pf_anchor_global_RB_REMOVE+0x81 sys/net/pf_ruleset.c:82
pf_remove_if_empty_ruleset(ffff80000167f6e0) at pf_remove_if_empty_ruleset+0x12d sys/net/pf_ruleset.c:301
pfi_dynaddr_setup(ffff80000164d7f8,0,1) at pfi_dynaddr_setup+0x671 sys/net/pf_if.c:508
pf_addr_setup(ffffffff83a43150,ffff80000164d7f8,0) at pf_addr_setup+0x46 sys/net/pf_ioctl.c:948
pfioctl(14900,cd60441a,ffff8000015dc000,83,ffff80003c90bca8) at pfioctl+0x9aee sys/net/pf_ioctl.c:2653
VOP_IOCTL(fffffd806c5ee208,cd60441a,ffff8000015dc000,83,fffffd8007ffd7b8,ffff80003c90bca8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd806b1c6db0,cd60441a,ffff8000015dc000,ffff80003c90bca8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:537
sys_ioctl(ffff80003c90bca8,ffff80002f0c1da0,ffff80002f0c1cf0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1
syscall(ffff80002f0c1da0) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002f0c1da0) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x86df37dd50, count: -10
ddb> machine ddbcpu 1
No such command
ddb> trace
pf_anchor_global_RB_REMOVE(ffffffff83a42cb8,ffff80000167f250) at pf_anchor_global_RB_REMOVE+0x81 sys/net/pf_ruleset.c:82
pf_remove_if_empty_ruleset(ffff80000167f6e0) at pf_remove_if_empty_ruleset+0x12d sys/net/pf_ruleset.c:301
pfi_dynaddr_setup(ffff80000164d7f8,0,1) at pfi_dynaddr_setup+0x671 sys/net/pf_if.c:508
pf_addr_setup(ffffffff83a43150,ffff80000164d7f8,0) at pf_addr_setup+0x46 sys/net/pf_ioctl.c:948
pfioctl(14900,cd60441a,ffff8000015dc000,83,ffff80003c90bca8) at pfioctl+0x9aee sys/net/pf_ioctl.c:2653
VOP_IOCTL(fffffd806c5ee208,cd60441a,ffff8000015dc000,83,fffffd8007ffd7b8,ffff80003c90bca8) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd806b1c6db0,cd60441a,ffff8000015dc000,ffff80003c90bca8) at vn_ioctl+0xea sys/kern/vfs_vnops.c:537
sys_ioctl(ffff80003c90bca8,ffff80002f0c1da0,ffff80002f0c1cf0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1
syscall(ffff80002f0c1da0) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002f0c1da0) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x86df37dd50, count: -10

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/13 16:23 openbsd ef90b149a753 9530ccf9 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-main protection_fault: pf_anchor_global_RB_REMOVE
2026/04/02 01:42 openbsd ffc378411de4 4b3d9a38 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-main protection_fault: pf_anchor_global_RB_REMOVE
2026/03/31 04:34 openbsd 0a71aa187b1b 4b3d9a38 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-main protection_fault: pf_anchor_global_RB_REMOVE
2026/03/28 06:45 openbsd 9d790fdba930 4b3d9a38 .config console log report [disk image] [bsd.gdb] [kernel image] ci-openbsd-multicore protection_fault: pf_anchor_global_RB_REMOVE
* Struck through repros no longer work on HEAD.