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: 14d, last: 9d08h
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 1422d 1510d 3/3 fixed on 2022/06/27 02:23
openbsd protection_fault: pf_anchor_global_RB_REMOVE (2) -1 5 136d 283d 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(ffffffff839ee860,ffff800010fdb250) at pf_anchor_global_RB_REMOVE+0x81 sys/net/pf_ruleset.c:82
pf_remove_if_empty_ruleset(ffff800010fdb6e0) at pf_remove_if_empty_ruleset+0x12d sys/net/pf_ruleset.c:301
pfi_dynaddr_setup(ffff800001646d48,0,1) at pfi_dynaddr_setup+0x671 sys/net/pf_if.c:508
pf_addr_setup(ffffffff839eecf8,ffff800001646d48,0) at pf_addr_setup+0x46 sys/net/pf_ioctl.c:948
pfioctl(14900,cd60441a,ffff8000015d6000,83,ffff800035cdb248) at pfioctl+0x9aee sys/net/pf_ioctl.c:2651
VOP_IOCTL(fffffd806ade0988,cd60441a,ffff8000015d6000,83,fffffd8007ffd820,ffff800035cdb248) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd8075b45078,cd60441a,ffff8000015d6000,ffff800035cdb248) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800035cdb248,ffff80003c921a80,ffff80003c9219d0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1
syscall(ffff80003c921a80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c921a80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6e6e893c3e0, count: -10
ddb> show registers
rdi               0xffff80002ccbc000
rsi                           0x113f    __ALIGN_SIZE+0x13f
rbp               0xffff80003c921450
rbx               0xffffffff839ee860    pf_anchors
rdx               0xffff80002ccbc000
rcx                           0x113e    __ALIGN_SIZE+0x13e
rax               0xffffffff8227ae9f    pf_anchor_global_RB_REMOVE+0x2f
r8                             0x3fc
r9                0x8080808080808080
r10                0xca12368cd86dafb
r11               0xdaf222314d9d6d5b
r12               0xc4b5496fe0397ce9
r13                              0x1
r14               0xffff800010fdb250
r15               0xcac321545c1a8a44
rip               0xffffffff8227aef1    pf_anchor_global_RB_REMOVE+0x81
cs                               0x8
rflags                       0x10282    __ALIGN_SIZE+0xf282
rsp               0xffff80003c921400
ss                              0x10
pf_anchor_global_RB_REMOVE+0x81:        movq    0(%r12),%r15
ddb> show proc
PROC (syz-executor) tid=228983 pid=5768 tcnt=2 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=0xffff800035cdba10,0xffff800035cd9260
    process=0xffff800035cdd218 user=0xffff80003c91c000, vmspace=0xfffffd806d67d188
    estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 81061  334427  72212      0  2        0x10                syz-executor
 81061  285702  72212      0  3   0x4000090  fsleep        syz-executor
  5768  238987  11551      0  2           0                syz-executor
* 5768  228983  11551      0  7   0x4000000                syz-executor
 29664  145483  42937      0  3        0x80  nanoslp       syz-executor
 29664  239510  42937      0  3   0x4000080  fsleep        syz-executor
 29664  405729  42937      0  3   0x4000080  fsleep        syz-executor
 98225  253198   7463      0  3        0x80  nanoslp       syz-executor
 98225  506951   7463      0  3   0x4000080  ttyretype     syz-executor
 75794  512476  73152      0  3        0x80  nanoslp       syz-executor
 75794  298702  73152      0  3   0x4000080  sbwait        syz-executor
 75794  187155  73152      0  3   0x4000080  fsleep        syz-executor
 27540  153662  99263      0  3        0x80  nanoslp       syz-executor
 27540  259372  99263      0  3   0x4000080  sbwait        syz-executor
 27540  482337  99263      0  3   0x4000080  fsleep        syz-executor
 15033  115962  10328      0  3      0x3010  suspend       syz-executor
 15033   37322  10328      0  2   0x4081010                syz-executor
 15033  260830  10328      0  3   0x4081010  inode         syz-executor
 99263  169098  55432      0  3        0x82  nanoslp       syz-executor
 10328  356905  55432      0  3        0x82  wait          syz-executor
  7463  415247  55432      0  3        0x82  nanoslp       syz-executor
 42937  517500  55432      0  3        0x82  nanoslp       syz-executor
 72212  258069  55432      0  3        0x82  nanoslp       syz-executor
 38265  385981  55432      0  3        0x82  wait          syz-executor
 11551  388002  55432      0  3        0x82  nanoslp       syz-executor
 73152  162580  55432      0  3        0x82  nanoslp       syz-executor
 55432  228931  37407      0  3        0x82  kqread        syz-executor
 37407  435413  26838      0  3    0x10008a  sigsusp       ksh
 26838  436021  92336      0  3        0x98  kqread        sshd-session
 92336  426591  86099      0  3        0x92  kqread        sshd-session
 88044  265064      1      0  3    0x100083  ttyin         getty
 86099     303      1      0  3        0x88  kqread        sshd
 33060  377754  75607     73  3   0x1100090  kqread        syslogd
 75607   44711      1      0  3    0x100082  sbwait        syslogd
 25888  217499      1      0  3    0x100080  kqread        resolvd
 39205   85067  51177     77  3    0x100092  kqread        dhcpleased
 25846  358734  51177     77  3    0x100092  kqread        dhcpleased
 51177  208900      1      0  3        0x80  kqread        dhcpleased
 47459  288247      0      0  3     0x14200  bored         smr
 41128  142072      0      0  2     0x14200                zerothread
  3931   86471      0      0  3     0x14200  aiodoned      aiodoned
 61351    1509      0      0  3     0x14200  syncer        update
 84596  365439      0      0  3     0x14200  cleaner       cleaner
 14192  270192      0      0  3     0x14200  reaper        reaper
 82108   25172      0      0  3     0x14200  pgdaemon      pagedaemon
 62375  430337      0      0  3     0x14200  bored         viomb
  6442   90805      0      0  3  0x40014200  acpi0         acpi0
 56669   65827      0      0  3     0x14200  bored         softnet0
 45901   75581      0      0  3     0x14200  bored         systqmp
 98527  110977      0      0  3     0x14200  bored         systq
 24735   10728      0      0  3  0x40014200  tmoslp        softclock
 65927  250691      0      0  3  0x40014200                idle0
     1  409135      0      0  3        0x82  wait          init
     0       0     -1      0  3  0x10010200  scheduler     swapper
ddb> show all locks
No such command
ddb> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf 11041  12120K   12368K 166960K     12328        0
            pcb    17     12K      12K 166960K        53        0
         rtable   217      7K       8K 166960K       395        0
             pf    35     14K      17K 166960K        60        0
         ifaddr    40      7K       7K 166960K        53        0
        ifgroup    50      2K       2K 166960K        67        0
         sysctl     4      1K       9K 166960K         8        0
       counters    33     17K      18K 166960K        46        0
       ioctlops     1      4K       4K 166960K        70        0
            iov     0      0K      12K 166960K         3        0
          mount     1      1K       1K 166960K         1        0
            log     0      0K       0K 166960K         4        0
         vnodes  1333     84K      84K 166960K      1505        0
      UFS quota     1     32K      32K 166960K         1        0
      UFS mount     5     36K      36K 166960K         5        0
            shm     2      1K       5K 166960K         5        0
         VM map     2      1K       1K 166960K         2        0
            sem     8      0K       0K 166960K        10        0
        dirhash    12      2K       2K 166960K        12        0
           ACPI  1692    195K     286K 166960K     12470        0
      file desc    18     65K      85K 166960K       294        0
          sigio     0      0K       0K 166960K         2        0
           proc    60     59K      91K 166960K       512        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        20        0
       in_multi    92      7K       7K 166960K       100        0
    ether_multi     1      0K       0K 166960K         1        0
            mrt     1      0K       0K 166960K         7        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       388        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   238    143K     160K 166960K      4307        0
       UVM aobj     7      4K       4K 166960K         9        0
     pinsyscall    39     78K      90K 166960K      1395        0
        memdesc     1      4K       4K 166960K         1        0
    crypto data     1      1K       1K 166960K         1        0
    ip6_options     0      0K       0K 166960K         9        0
            NDP    11      0K       2K 166960K        34        0
           temp    38   9063K    9128K 166960K      6206        0
         kqueue    14     22K      30K 166960K        52        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       53    0       47     1     0     1     1     0     8    0
rtentry    136      113    0       19     4     0     4     4     0     8    0
unpcb      144      198    0      181     4     3     1     4     0     8    0
syncache   336        5    0        5     1     1     0     1     0     8    0
tcpqe       32        1    0        1     1     1     0     1     0     8    0
tcpcb      736       58    0       52     2     1     1     2     0     8    0
arp         96       18    0        0     1     0     1     1     0     8    0
inpcb      328      189    0      177     2     0     2     2     0     8    0
ip6q        72        2    0        0     1     0     1     1     0     8    0
ip6af       40        3    0        1     1     0     1     1     0     8    0
nd6        112       25    0        3     1     0     1     1     0     8    0
pkpcb       40        2    0        2     1     1     0     1     0     8    0
kcovpl      48        8    0        0     1     0     1     1     0     8    0
ppxss      1072      12    0       12     1     1     0     1     0     8    0
pfstscr     40        1    0        1     1     1     0     1     0     8    0
pfrktable  1344       2    1        2     2     1     1     1     0     8    1
pfanchor   1288       1    0        1     1     0     1     1     0     8    1
pftag       88        1    0        1     1     1     0     1     0     8    0
pfstkey    128        1    0        1     1     1     0     1     0     8    0
pfstate    384        1    0        1     1     1     0     1     0     8    0
pfrule     1360       3    0        2     2     1     1     1     0     8    0
rttmr      136        1    0        1     1     1     0     1     0     8    0
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256      455    0       59    29     1    28    29     0     8    0
art_table   40      456    0       59     5     0     5     5     0     8    0
art_node    32      113    0       28     1     0     1     1     0     8    0
sysvmsgpl   40       41    0        1     1     0     1     1     0     8    0
semapl     112        7    0        1     1     0     1     1     0     8    0
shmpl      112        6    0        2     1     0     1     1     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino2pl    256     1845    0      382    92     0    92    92     0     8    0
ffsino     256     1845    0      382    92     0    92    92     0     8    0
nchpl      144     2257    0      562    64     0    64    64     0     8    0
rtmask      32        4    0        4     1     1     0     1     0     8    0
vnodes     216     2027    0        0   113     0   113   113     0     8    0
namei      1024    7028    0     7027     1     0     1     1     0     8    0
pfiaddrpl  120        1    0        0     1     0     1     1     0     8    0
kstatmem   264       36    0       14     2     0     2     2     0     8    0
scxspl     216    11255    0    11255     8     7     1     8     1     8    1
plimitpl   152      123    0      104     1     0     1     1     0     8    0
sigapl     424      590    0      547     6     1     5     6     0     8    0
knotepl    120    10013    0     9728    15     6     9    15     0     8    0
kqueuepl   184       67    0       56     1     0     1     1     0     8    0
pipepl     304      130    0      103     3     0     3     3     0     8    0
fdescpl    448      576    0      546     4     0     4     4     0     8    0
filepl     120     2589    0     2325    13     2    11    13     0     8    0
lockfpl    104       69    0       65     1     0     1     1     0     8    0
lockfspl    48       34    0       30     1     0     1     1     0     8    0
sessionpl  144       24    0       16     1     0     1     1     0     8    0
pgrppl      48       32    0       16     1     0     1     1     0     8    0
ucredpl    104      302    0      289     1     0     1     1     0     8    0
zombiepl   144      549    0      547     1     0     1     1     0     8    0
processpl  1152     590    0      547     4     0     4     4     0     8    0
procpl     664      835    0      781     6     1     5     6     0     8    0
sockpl     552      453    0      418     8     5     3     8     0     8    0
mcl64k     65536      7    0        7     1     1     0     1     0     8    0
mcl16k     16384      1    0        1     1     1     0     1     0     8    0
mcl8k      8192       8    0        8     1     1     0     1     0     8    0
mcl4k      4096    2696    0     2643    14     6     8    14     0     8    0
mcl2k      2048     280    0      279     2     1     1     2     0     8    0
mtagpl      96       10    0        7     1     0     1     1     0     8    0
mbufpl     256     5882    0     5681    14     0    14    14     0     8    0
bufpl      280     4427    0      105   309     0   309   309     0     8    0
anonpl      24   120796    0   114597    55     0    55    55     0   187    0
amapchunkpl 152   12898    0    12370    27     6    21    26     0   158    0
amappl16   200     2403    0     2213    19     3    16    19     0     8    0
amappl15   192        6    0        6     1     1     0     1     0     8    0
amappl14   184      415    0      413     1     0     1     1     0     8    0
amappl13   176      145    0      135     1     0     1     1     0     8    0
amappl12   168      812    0      783     2     0     2     2     0     8    0
amappl11   160        5    0        5     1     1     0     1     0     8    0
amappl10   152       91    0       81     1     0     1     1     0     8    0
amappl9    144      260    0      260     1     1     0     1     0     8    0
amappl8    136      109    0      107     1     0     1     1     0     8    0
amappl7    128      165    0      154     1     0     1     1     0     8    0
amappl6    120      154    0      153     1     0     1     1     0     8    0
amappl5    112       87    0       79     1     0     1     1     0     8    0
amappl4    104      257    0      242     1     0     1     1     0     8    0
amappl3     96     2471    0     2353     4     0     4     4     0     8    0
amappl2     88      521    0      467     2     0     2     2     0     8    0
amappl1     80    10013    0     9467    15     1    14    15     0     8    0
amappl      88     3586    0     3409     5     0     5     5     0    92    0
uvmvnodes   80      101    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        8    0        2     1     0     1     1     0     8    0
uaddrrnd    24      576    0      546     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      576    0      546     1     0     1     1     0     8    0
vmmpekpl   168     6245    0     6218     2     0     2     2     0     8    0
vmmpepl    168    45150    0    43154    99     5    94    99     0   357    0
vmsppl     368      575    0      546     4     1     3     4     0     8    0
rwobjpl     40    15732    0    14608    14     0    14    14     0     8    0
pdppl      4096    1158    0     1092    90    24    66    76     0     8    0
pvpl        32   287585    0   275191   121     0   121   121     0   265    0
pmappl     216      575    0      546     2     0     2     2     0     8    0
extentpl    40       45    0       27     1     0     1     1     0     8    0
phpool     112      357    0       41    10     0    10    10     0     8    0
ddb> machine ddbcpu 0
No such command
ddb> trace
pf_anchor_global_RB_REMOVE(ffffffff839ee860,ffff800010fdb250) at pf_anchor_global_RB_REMOVE+0x81 sys/net/pf_ruleset.c:82
pf_remove_if_empty_ruleset(ffff800010fdb6e0) at pf_remove_if_empty_ruleset+0x12d sys/net/pf_ruleset.c:301
pfi_dynaddr_setup(ffff800001646d48,0,1) at pfi_dynaddr_setup+0x671 sys/net/pf_if.c:508
pf_addr_setup(ffffffff839eecf8,ffff800001646d48,0) at pf_addr_setup+0x46 sys/net/pf_ioctl.c:948
pfioctl(14900,cd60441a,ffff8000015d6000,83,ffff800035cdb248) at pfioctl+0x9aee sys/net/pf_ioctl.c:2651
VOP_IOCTL(fffffd806ade0988,cd60441a,ffff8000015d6000,83,fffffd8007ffd820,ffff800035cdb248) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd8075b45078,cd60441a,ffff8000015d6000,ffff800035cdb248) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800035cdb248,ffff80003c921a80,ffff80003c9219d0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1
syscall(ffff80003c921a80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c921a80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6e6e893c3e0, count: -10
ddb> machine ddbcpu 1
No such command
ddb> trace
pf_anchor_global_RB_REMOVE(ffffffff839ee860,ffff800010fdb250) at pf_anchor_global_RB_REMOVE+0x81 sys/net/pf_ruleset.c:82
pf_remove_if_empty_ruleset(ffff800010fdb6e0) at pf_remove_if_empty_ruleset+0x12d sys/net/pf_ruleset.c:301
pfi_dynaddr_setup(ffff800001646d48,0,1) at pfi_dynaddr_setup+0x671 sys/net/pf_if.c:508
pf_addr_setup(ffffffff839eecf8,ffff800001646d48,0) at pf_addr_setup+0x46 sys/net/pf_ioctl.c:948
pfioctl(14900,cd60441a,ffff8000015d6000,83,ffff800035cdb248) at pfioctl+0x9aee sys/net/pf_ioctl.c:2651
VOP_IOCTL(fffffd806ade0988,cd60441a,ffff8000015d6000,83,fffffd8007ffd820,ffff800035cdb248) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd8075b45078,cd60441a,ffff8000015d6000,ffff800035cdb248) at vn_ioctl+0xea sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800035cdb248,ffff80003c921a80,ffff80003c9219d0) at sys_ioctl+0x660 sys/kern/sys_generic.c:-1
syscall(ffff80003c921a80) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c921a80) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6e6e893c3e0, count: -10

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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.