syzbot


panic: rw_enter: pf_state_lock locking against myself

Status: fixed on 2021/02/10 08:50
Reported-by: syzbot+d6ea8620b43dc69ecbc6@syzkaller.appspotmail.com
Fix commit: d7220220b7ed pfsync_state_import() must not be called with the pf state lock held, since the actual modification of the state table is done by a call to pf_state_insert(), which takes the pf state lock itself. Other calls to pfsync_state_import() also only have the pf lock.
First crash: 661d, last: 661d

Sample crash report:
login: panic: rw_enter: pf_state_lock locking against myself
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 50330  76539      0         0x2          0    0  syz-executor6837
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823e4940) at panic+0x15e sys/kern/subr_prf.c:218
rw_enter(ffffffff826fc3e0,1) at rw_enter+0x36f sys/kern/kern_rwlock.c:174
pf_state_insert(ffff8000006af800,ffff8000216c4e18,ffff8000216c4e20,fffffd806d1bbb40) at pf_state_insert+0xa0 sys/net/pf.c:951
pfsync_state_import(ffff800000acda00,1) at pfsync_state_import+0xcbe sys/net/if_pfsync.c:699
pfioctl(4900,c1084425,ffff800000acda00,3,ffff800021696010) at pfioctl+0x50ac sys/net/pf_ioctl.c:1729
VOP_IOCTL(fffffd807305dda0,c1084425,ffff800000acda00,3,fffffd807f7b7a20,ffff800021696010) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:297
vn_ioctl(fffffd806e6bf008,c1084425,ffff800000acda00,ffff800021696010) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800021696010,ffff8000216c52c8,ffff8000216c5310) at sys_ioctl+0x4ac
syscall(ffff8000216c5390) at syscall+0x507 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff77e0, count: 4
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports.  Insufficient info makes it difficult to find and fix bugs.
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
rw_enter: pf_state_lock locking against myself
ddb> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823e4940) at panic+0x15e sys/kern/subr_prf.c:218
rw_enter(ffffffff826fc3e0,1) at rw_enter+0x36f sys/kern/kern_rwlock.c:174
pf_state_insert(ffff8000006af800,ffff8000216c4e18,ffff8000216c4e20,fffffd806d1bbb40) at pf_state_insert+0xa0 sys/net/pf.c:951
pfsync_state_import(ffff800000acda00,1) at pfsync_state_import+0xcbe sys/net/if_pfsync.c:699
pfioctl(4900,c1084425,ffff800000acda00,3,ffff800021696010) at pfioctl+0x50ac sys/net/pf_ioctl.c:1729
VOP_IOCTL(fffffd807305dda0,c1084425,ffff800000acda00,3,fffffd807f7b7a20,ffff800021696010) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:297
vn_ioctl(fffffd806e6bf008,c1084425,ffff800000acda00,ffff800021696010) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800021696010,ffff8000216c52c8,ffff8000216c5310) at sys_ioctl+0x4ac
syscall(ffff8000216c5390) at syscall+0x507 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff77e0, count: -11
ddb> show registers
rdi                                0
rsi                              0x1
rbp               0xffff8000216c4c40
rbx               0xffff8000216c4c50
rdx                             0x8b
rcx                              0x2
rax                              0x1
r8                0xffffffff81034bd5    kprintf+0x155
r9                               0x1
r10               0xa4734d6a10230b83
r11               0x7ef2d22de7b6c997
r12                     0x3000000008
r13               0xffff8000216c4cf0
r14                            0x100
r15                              0x1
rip               0xffffffff81116418    db_enter+0x18
cs                               0x8
rflags                         0x246
rsp               0xffff8000216c4c30
ss                              0x10
db_enter+0x18:  addq    $0x8,%rsp
ddb> show proc
PROC (syz-executor6837) pid=50330 stat=onproc
    flags process=2<EXEC,8ORPHAN> proc=0
    pri=51, usrpri=51, nice=20
    forw=0xffffffffffffffff, list=0xffff8000216967f0,0xffffffff827feb10
    process=0xffff800021698808 user=0xffff8000216c0000, vmspace=0xfffffd807effd110
    estcpu=1, cpticks=1, pctcpu=0.0
    user=0, sys=1, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
*76539   50330  12842      0  7         0x2                syz-executor6837
 12842  429229  88143      0  3    0x10008a  sigsusp       ksh
 88143  428083  46894      0  2        0x12                sshd
 52681   46528      1      0  3    0x100083  ttyin         getty
 46894  134037      1      0  3        0x80  select        sshd
 14924  205020  88583     73  3    0x100090  kqread        syslogd
 88583  348207      1      0  3    0x100082  netio         syslogd
 78983  340581      1     77  3    0x100090  poll          dhclient
 64712   55116      1      0  3        0x80  poll          dhclient
 89093  514895      0      0  3     0x14200  bored         smr
 71304  422615      0      0  2     0x14200                zerothread
 74800  470955      0      0  3     0x14200  aiodoned      aiodoned
 35148  292066      0      0  3     0x14200  syncer        update
 58856  492020      0      0  3     0x14200  cleaner       cleaner
 29535   93131      0      0  3     0x14200  reaper        reaper
  6392  105221      0      0  3     0x14200  pgdaemon      pagedaemon
 86054  177923      0      0  3     0x14200  bored         crynlk
 92003  290599      0      0  3     0x14200  bored         crypto
 66733  367052      0      0  3     0x14200  bored         viomb
 49240  152916      0      0  3  0x40014200  acpi0         acpi0
 60390  128459      0      0  3     0x14200  bored         softnet
  1917  492575      0      0  3     0x14200  bored         systqmp
  3411  312592      0      0  3     0x14200  bored         systq
 46185  499736      0      0  3  0x40014200  bored         softclock
 57684  181070      0      0  3  0x40014200                idle0
     1  152872      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  9457   6337K    6338K  78643K     10547        0
            pcb    13      8K       8K  78643K        13        0
         rtable    61      2K       2K  78643K       117        0
         ifaddr    25      7K       7K  78643K        25        0
       counters    19     16K      16K  78643K        19        0
       ioctlops     1      0K       2K  78643K        14        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1182     74K      74K  78643K      1187        0
      UFS quota     1     32K      32K  78643K         1        0
      UFS mount     5     36K      36K  78643K         5        0
            shm     2      1K       1K  78643K         2        0
         VM map     2      0K       0K  78643K         2        0
            sem     2      0K       0K  78643K         2        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1697    195K     286K  78643K     12598        0
      file desc     1      0K       0K  78643K         1        0
           proc    47     38K      46K  78643K       284        0
    NFS srvsock     1      0K       0K  78643K         1        0
     NFS daemon     1     16K      16K  78643K         1        0
       in_multi    11      0K       0K  78643K        11        0
    ether_multi     1      0K       0K  78643K         1        0
    ISOFS mount     1     32K      32K  78643K         1        0
  MSDOSFS mount     1     16K      16K  78643K         1        0
           ttys    19     95K      95K  78643K        19        0
           exec     0      0K       2K  78643K       261        0
        pagedep     1      8K       8K  78643K         1        0
       inodedep     1     32K      32K  78643K         1        0
         newblk     1      0K       0K  78643K         1        0
        VM swap     7     26K      26K  78643K         7        0
       UVM amap    31      1K       2K  78643K       513        0
       UVM aobj     3      2K       2K  78643K         3        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
            NDP     3      0K       0K  78643K         3        0
           temp    18   3953K    4017K  78643K      1442        0
         kqueue     2      2K       2K  78643K         2        0
      SYN cache     2     16K      16K  78643K         2        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
rtpcb      120       15    0       13     1     0     1     1     0     8    0
rtentry    112       23    0        1     1     0     1     1     0     8    0
unpcb      120       27    0       19     1     0     1     1     0     8    0
syncache   296        5    0        5     2     1     1     1     0     8    1
tcpcb      736        8    0        5     1     0     1     1     0     8    0
inpcb      304       22    0       16     1     0     1     1     0     8    0
pfstscr     40        2    0        0     1     0     1     1     0     8    0
pfstkey    112        2    0        0     1     0     1     1     0     8    0
pfstate    320        1    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       96    0        0     6     0     6     6     0     8    0
art_table   32       97    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
dino2pl    256     1389    0       15    86     0    86    86     0     8    0
ffsino     240     1389    0       15    81     0    81    81     0     8    0
nchpl      144     1563    0       31    57     0    57    57     0     8    0
uvmvnodes   72     1398    0        0    26     0    26    26     0     8    0
vnodes     224     1398    0        0    83     0    83    83     0     8    0
namei      1024    3490    0     3490     2     1     1     1     0     8    1
scxspl     216     3214    0     3214     1     0     1     1     0     8    1
plimitpl   152       13    0        8     1     0     1     1     0     8    0
sigapl     424      192    0      166     4     0     4     4     0     8    0
knotepl    112        5    0        0     1     0     1     1     0     8    0
kqueuepl   168        1    0        0     1     0     1     1     0     8    0
pipepl     304       57    0       53     2     1     1     1     0     8    0
fdescpl    432      177    0      166     2     0     2     2     0     8    0
filepl     120      823    0      779     2     0     2     2     0     8    0
lockfpl    104        5    0        4     1     0     1     1     0     8    0
lockfspl    48        3    0        2     1     0     1     1     0     8    0
sessionpl  144       17    0        9     1     0     1     1     0     8    0
pgrppl      48       17    0        9     1     0     1     1     0     8    0
ucredpl     96       57    0       50     1     0     1     1     0     8    0
zombiepl   144      166    0      166     2     1     1     1     0     8    1
processpl  1016     192    0      166     4     0     4     4     0     8    0
procpl     672      192    0      166     3     0     3     3     0     8    0
sockpl     432       64    0       48     2     0     2     2     0     8    0
mcl4k      4096      10    0       10     2     1     1     1     0     8    1
mcl2k      2048    6116    0     6082     9     3     6     8     0     8    1
mtagpl      96        2    0        2     1     1     0     1     0     8    0
mbufpl     256     7788    0     7741     6     2     4     5     0     8    0
bufpl      280     1902    0      100   129     0   129   129     0     8    0
anonpl      24    18063    0    16937    11     3     8    10     0   188    1
amapchunkpl 152     474    0      439     3     1     2     3     0   158    0
amappl16   200       70    0       65     1     0     1     1     0     8    0
amappl15   192        1    0        0     1     0     1     1     0     8    0
amappl14   184       23    0       20     1     0     1     1     0     8    0
amappl13   176       12    0       11     2     1     1     1     0     8    0
amappl12   168       11    0       11     1     1     0     1     0     8    0
amappl11   160       42    0       33     1     0     1     1     0     8    0
amappl10   152        6    0        4     1     0     1     1     0     8    0
amappl9    144      215    0      215     2     1     1     1     0     8    1
amappl8    136       56    0       55     1     0     1     1     0     8    0
amappl7    128      181    0      180     1     0     1     1     0     8    0
amappl6    120       52    0       45     1     0     1     1     0     8    0
amappl5    112      337    0      323     1     0     1     1     0     8    0
amappl4    104      238    0      218     1     0     1     1     0     8    0
amappl3     96       91    0       84     1     0     1     1     0     8    0
amappl2     88      745    0      700     2     0     2     2     0     8    0
amappl1     80    12564    0    12171    18     7    11    18     0     8    0
amappl      88      351    0      333     1     0     1     1     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      64        2    0        0     1     0     1     1     0     8    0
uaddrrnd    24      177    0      166     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      177    0      166     1     0     1     1     0     8    0
vmmpekpl   168     5289    0     5274     1     0     1     1     0     8    0
vmmpepl    168    26383    0    25637    48    12    36    48     0   357    2
vmsppl     272      176    0      166     1     0     1     1     0     8    0
rwobjpl     24     6925    0     6424     6     2     4     6     0     8    0
pdppl      4096     360    0      332    40    12    28    34     0     8    0
pvpl        32    72207    0    69458    28     2    26    26     0   265    3
pmappl     200      176    0      166     1     0     1     1     0     8    0
extentpl    40       58    0       40     1     0     1     1     0     8    0
phpool     112      245    0       21     7     0     7     7     0     8    0
ddb> machine ddbcpu 0
No such command
ddb> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823e4940) at panic+0x15e sys/kern/subr_prf.c:218
rw_enter(ffffffff826fc3e0,1) at rw_enter+0x36f sys/kern/kern_rwlock.c:174
pf_state_insert(ffff8000006af800,ffff8000216c4e18,ffff8000216c4e20,fffffd806d1bbb40) at pf_state_insert+0xa0 sys/net/pf.c:951
pfsync_state_import(ffff800000acda00,1) at pfsync_state_import+0xcbe sys/net/if_pfsync.c:699
pfioctl(4900,c1084425,ffff800000acda00,3,ffff800021696010) at pfioctl+0x50ac sys/net/pf_ioctl.c:1729
VOP_IOCTL(fffffd807305dda0,c1084425,ffff800000acda00,3,fffffd807f7b7a20,ffff800021696010) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:297
vn_ioctl(fffffd806e6bf008,c1084425,ffff800000acda00,ffff800021696010) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800021696010,ffff8000216c52c8,ffff8000216c5310) at sys_ioctl+0x4ac
syscall(ffff8000216c5390) at syscall+0x507 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff77e0, count: -11
ddb> machine ddbcpu 1
No such command
ddb> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic(ffffffff823e4940) at panic+0x15e sys/kern/subr_prf.c:218
rw_enter(ffffffff826fc3e0,1) at rw_enter+0x36f sys/kern/kern_rwlock.c:174
pf_state_insert(ffff8000006af800,ffff8000216c4e18,ffff8000216c4e20,fffffd806d1bbb40) at pf_state_insert+0xa0 sys/net/pf.c:951
pfsync_state_import(ffff800000acda00,1) at pfsync_state_import+0xcbe sys/net/if_pfsync.c:699
pfioctl(4900,c1084425,ffff800000acda00,3,ffff800021696010) at pfioctl+0x50ac sys/net/pf_ioctl.c:1729
VOP_IOCTL(fffffd807305dda0,c1084425,ffff800000acda00,3,fffffd807f7b7a20,ffff800021696010) at VOP_IOCTL+0x91 sys/kern/vfs_vops.c:297
vn_ioctl(fffffd806e6bf008,c1084425,ffff800000acda00,ffff800021696010) at vn_ioctl+0xb5 sys/kern/vfs_vnops.c:531
sys_ioctl(ffff800021696010,ffff8000216c52c8,ffff8000216c5310) at sys_ioctl+0x4ac
syscall(ffff8000216c5390) at syscall+0x507 sys/arch/amd64/amd64/trap.c:590
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff77e0, count: -11
ddb> 

Crashes (8):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-openbsd-main 2021/02/10 00:25 openbsd 0049eb19c27a 2bd9619f .config log report syz C panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-multicore 2021/02/09 23:31 openbsd 0049eb19c27a 2bd9619f .config log report syz C panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-main 2021/02/09 23:14 openbsd 0049eb19c27a 2bd9619f .config log report panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-main 2021/02/09 23:13 openbsd 0049eb19c27a 2bd9619f .config log report panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-main 2021/02/09 23:09 openbsd 0049eb19c27a 2bd9619f .config log report panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-main 2021/02/09 23:08 openbsd 0049eb19c27a 2bd9619f .config log report panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-multicore 2021/02/09 23:05 openbsd 0049eb19c27a 2bd9619f .config log report panic: rw_enter: pf_state_lock locking against myself
ci-openbsd-multicore 2021/02/09 23:01 openbsd 0049eb19c27a 2bd9619f .config log report panic: rw_enter: pf_state_lock locking against myself
* Struck through repros no longer work on HEAD.