syzbot


witness: reversal: vmmaplk inode (2)

Status: closed as invalid on 2020/10/27 19:49
Reported-by: syzbot+06cee7cfc759eb863aa2@syzkaller.appspotmail.com
First crash: 1800d, last: 1486d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
openbsd witness: reversal: vmmaplk inode C 103124 1800d 2127d 3/3 fixed on 2019/12/18 19:18
openbsd witness: reversal: vmmaplk inode (3) C 1050 1d13h 918d 0/3 upstream: reported C repro on 2022/05/18 16:04

Sample crash report:
login: witness: lock order reversal:
 1st 0xfffffd806e9aa300 vmmaplk (&map->lock)
 2nd 0xfffffd806fc14928 inode (&ip->i_lock)
lock order "&ip->i_lock"(rrwlock) -> "&map->lock"(rwlock) first seen at:
#0  witness_checkorder+0x69c witness_lock_order_check sys/kern/subr_witness.c:2442 [inline]
#0  witness_checkorder+0x69c sys/kern/subr_witness.c:873
#1  rw_enter_read+0x66 sys/kern/kern_rwlock.c:109
#2  uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1448
#3  uvm_fault+0x7f sys/uvm/uvm_fault.c:524
#4  pageflttrap+0x1b8 sys/arch/amd64/amd64/trap.c:221
#5  kerntrap+0xec sys/arch/amd64/amd64/trap.c:302
#6  alltraps_kern_meltdown+0x7b
#7  copyout+0x53
#8  ffs_read+0x3d2 sys/ufs/ffs/ffs_vnops.c:258
#9  VOP_READ+0xbf sys/kern/vfs_vops.c:247
#10 vn_read+0x124 sys/kern/vfs_vnops.c:375
#11 dofilereadv+0x1a1 sys/kern/sys_generic.c:237
#12 sys_read+0x83 sys/kern/sys_generic.c:157
#13 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#13 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#14 Xsyscall+0x128
lock order "&map->lock"(rwlock) -> "&ip->i_lock"(rrwlock) first seen at:
#0  witness_checkorder+0x69c witness_lock_order_check sys/kern/subr_witness.c:2442 [inline]
#0  witness_checkorder+0x69c sys/kern/subr_witness.c:873
#1  rw_enter+0xd4
#2  rrw_enter+0x88 sys/kern/kern_rwlock.c:453
#3  VOP_LOCK+0x4b sys/kern/vfs_vops.c:602
#4  vn_lock+0x81 sys/kern/vfs_vnops.c:575
#5  uvn_io+0x2c8 sys/uvm/uvm_vnode.c:1196
#6  uvn_get+0x226 sys/uvm/uvm_vnode.c:1056
#7  uvm_fault+0x11cc sys/uvm/uvm_fault.c:1023
#8  uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1295
#9  uvm_map_pageable_wire+0x2dd sys/uvm/uvm_map.c:2358
#10 sys_mlock+0x185 sys/uvm/uvm_mmap.c:765
#11 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#11 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#12 Xsyscall+0x128
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
ddb{1}> 
ddb{1}> set $lines = 0
ddb{1}> set $maxwidth = 0
ddb{1}> show panic
the kernel did not panic
ddb{1}> trace
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
witness_checkorder(fffffd806fc14928,9,0) at witness_checkorder+0x1009 witness_debugger sys/kern/subr_witness.c:2505 [inline]
witness_checkorder(fffffd806fc14928,9,0) at witness_checkorder+0x1009 sys/kern/subr_witness.c:1087
rw_enter(fffffd806fc14918,81) at rw_enter+0xd4
rrw_enter(fffffd806fc14918,81) at rrw_enter+0x88 sys/kern/kern_rwlock.c:453
VOP_LOCK(fffffd806fc15770,81) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:602
vn_lock(fffffd806fc15770,81) at vn_lock+0x81 sys/kern/vfs_vnops.c:575
uvn_io(fffffd806df11680,ffff800020b2f268,1,2,0) at uvn_io+0x2c8 sys/uvm/uvm_vnode.c:1196
uvn_get(fffffd806df11680,0,ffff800020b2f4c0,ffff800020b2f454,0,1) at uvn_get+0x226 sys/uvm/uvm_vnode.c:1056
uvm_fault(fffffd806e9aa2e8,20002000,2,3) at uvm_fault+0x11cc sys/uvm/uvm_fault.c:1023
uvm_fault_wire(fffffd806e9aa2e8,20002000,20003000,3) at uvm_fault_wire+0x70 sys/uvm/uvm_fault.c:1295
uvm_map_pageable_wire(fffffd806e9aa2e8,fffffd806e364ee0,fffffd806e364268,0,0,0) at uvm_map_pageable_wire+0x2dd sys/uvm/uvm_map.c:2358
sys_mlock(ffff800020a7cea8,ffff800020b2f6b8,ffff800020b2f700) at sys_mlock+0x185 sys/uvm/uvm_mmap.c:765
syscall(ffff800020b2f780) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
syscall(ffff800020b2f780) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x54099eddc10, count: -14
ddb{1}> show registers
rdi                              0x3
rsi               0xffffffff82502c30    __sancov_gen_cov_switch_values.129
rbp               0xffff800020b2eee0
rbx                              0x3
rdx                             0x8b
rcx                              0x3
rax                              0x3
r8                0xffffffff81c63a92    witness_checkorder+0xfe2
r9                               0x5
r10               0xc482c5aafc79c714
r11               0xc536319cb6e13d53
r12               0xfffffd80029a82c0
r13                                0
r14               0xffffffff82623050    w_lodata+0x4f470
r15               0xffffffff82627d50    w_lodata+0x54170
rip               0xffffffff8219a9e8    db_enter+0x18
cs                               0x8
rflags                         0x246
rsp               0xffff800020b2eed0
ss                              0x10
db_enter+0x18:  addq    $0x8,%rsp
ddb{1}> show proc
PROC (syz-executor8489) pid=135360 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=32, usrpri=51, nice=20
    forw=0xffffffffffffffff, list=0xffff800020a7c008,0xffffffff82682e08
    process=0xffff800020a903d0 user=0xffff800020b2a000, vmspace=0xfffffd806e9aa2e8
    estcpu=2, cpticks=0, pctcpu=0.0
    user=0, sys=0, intr=0
ddb{1}> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 64560   92526  63025      0  7           0                syz-executor8489
 64560   19696  63025      0  2   0x4000000                syz-executor8489
*64560  135360  63025      0  7   0x4000000                syz-executor8489
 63025  397455  84687      0  3        0x82  nanosleep     syz-executor8489
 84687  153080  28809      0  3    0x10008a  pause         ksh
 28809  522366   6307      0  3        0x92  select        sshd
 44278  140188      1      0  3    0x100083  ttyin         getty
  6307    8296      1      0  3        0x80  select        sshd
 65752  386093  93819     74  3    0x100092  bpf           pflogd
 93819   90295      1      0  3        0x80  netio         pflogd
 28084  106759  27592     73  3    0x100090  kqread        syslogd
 27592  370625      1      0  3    0x100082  netio         syslogd
 21612  346799      1     77  3    0x100090  poll          dhclient
 52296  125603      1      0  3        0x80  poll          dhclient
 26393   47549      0      0  3     0x14200  bored         smr
 81580  388517      0      0  3     0x14200  pgzero        zerothread
 13202  338080      0      0  3     0x14200  aiodoned      aiodoned
 94690  501905      0      0  3     0x14200  syncer        update
 59420   52740      0      0  3     0x14200  cleaner       cleaner
 39232  235718      0      0  3     0x14200  reaper        reaper
 31946  109140      0      0  3     0x14200  pgdaemon      pagedaemon
 77512  234566      0      0  3     0x14200  bored         crynlk
 64730  375484      0      0  3     0x14200  bored         crypto
 84125  213551      0      0  3  0x40014200  acpi0         acpi0
 86373  179671      0      0  3  0x40014200                idle1
 56647  105072      0      0  3     0x14200  bored         softnet
 96461  178433      0      0  3     0x14200  bored         systqmp
 25483   50107      0      0  3     0x14200  bored         systq
 50190  440363      0      0  3  0x40014200  bored         softclock
 25616  278632      0      0  3  0x40014200                idle0
     1  391902      0      0  3        0x82  wait          init
     0       0     -1      0  3     0x10200  scheduler     swapper
ddb{1}> show all locks
Process 64560 (syz-executor8489) thread 0xffff800020a7cea8 (135360)
shared rwlock vmmaplk r = 0 (0xfffffd806e9aa300)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1164
#1  rw_enter+0x453 sys/kern/kern_rwlock.c:309
#2  vm_map_lock_ln+0x111 sys/uvm/uvm_map.c:5409
#3  uvm_map_pageable+0x11d sys/uvm/uvm_map.c:2454
#4  sys_mlock+0x185 sys/uvm/uvm_mmap.c:765
#5  syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline]
#5  syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570
#6  Xsyscall+0x128
exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82641eb8)
#0  witness_lock+0x52e sys/kern/subr_witness.c:1164
#1  syscall+0x400 mi_syscall sys/sys/syscall_mi.h:93 [inline]
#1  syscall+0x400 sys/arch/amd64/amd64/trap.c:570
#2  Xsyscall+0x128
ddb{1}> show malloc
           Type InUse  MemUse  HighUse   Limit  Requests Type Lim
         devbuf  9462   6393K    6394K  78643K     10553        0
            pcb    13      8K       8K  78643K        13        0
         rtable    61      2K       2K  78643K       127        0
         ifaddr    29      8K       8K  78643K        30        0
       counters    39     33K      33K  78643K        39        0
       ioctlops     0      0K       4K  78643K      1467        0
          mount     1      1K       1K  78643K         1        0
         vnodes  1183     74K      75K  78643K      1188        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      1K       1K  78643K         2        0
            sem     2      0K       0K  78643K         2        0
        dirhash    12      2K       2K  78643K        12        0
           ACPI  1809    196K     290K  78643K     12766        0
      file desc     1      0K       0K  78643K         1        0
           proc    59     63K      71K  78643K       358        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       1K  78643K       177        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    65      3K       4K  78643K       807        0
       UVM aobj     2      2K       2K  78643K         2        0
        memdesc     1      4K       4K  78643K         1        0
    crypto data     1      1K       1K  78643K         1        0
            NDP     4      0K       0K  78643K         4        0
           temp    24   3009K    3073K  78643K      1665        0
         kqueue     2      2K       2K  78643K         2        0
      SYN cache     2     16K      16K  78643K         2        0
ddb{1}> 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
plcache    128       20    0        0     1     0     1     1     0     8    0
rtpcb       80       15    0       13     1     0     1     1     0     8    0
rtentry    112       23    0        1     1     0     1     1     0     8    0
unpcb      120       29    0       19     1     0     1     1     0     8    0
syncache   264        5    0        5     2     1     1     1     0     8    1
tcpcb      544        8    0        5     1     0     1     1     0     8    0
inpcb      280       29    0       23     1     0     1     1     0     8    0
pfosfp      40      846    0      423     5     0     5     5     0     8    0
pfosfpen   112     1428    0      714    21     0    21    21     0     8    0
pfstitem    24        8    0        2     1     0     1     1     0     8    0
pfstkey    112        8    0        2     1     0     1     1     0     8    0
pfstate    328        8    0        2     1     0     1     1     0     8    0
pfrule     1360      21    0       16     2     1     1     2     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
dino1pl    128     1401    0       16    45     0    45    45     0     8    0
ffsino     272     1401    0       16    93     0    93    93     0     8    0
nchpl      144     1578    0       35    58     0    58    58     0     8    0
uvmvnodes   72     1411    0        0    26     0    26    26     0     8    0
vnodes     208     1411    0        0    75     0    75    75     0     8    0
namei      1024    3749    0     3749     2     1     1     1     0     8    1
percpumem   16       30    0        0     1     0     1     1     0     8    0
scxspl     192     2917    0     2917     9     8     1     7     0     8    1
plimitpl   152       14    0        8     1     0     1     1     0     8    0
sigapl     424      222    0      193     4     0     4     4     0     8    0
futexpl     56        5    0        5     1     0     1     1     0     8    1
knotepl    112        5    0        0     1     0     1     1     0     8    0
kqueuepl   144        1    0        0     1     0     1     1     0     8    0
pipelkpl    48       64    0       60     2     1     1     1     0     8    0
pipepl     120      128    0      121     2     1     1     1     0     8    0
fdescpl    496      207    0      193     3     0     3     3     0     8    0
filepl     152      966    0      916     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  112       18    0        9     1     0     1     1     0     8    0
pgrppl      48       18    0        9     1     0     1     1     0     8    0
ucredpl     96       52    0       43     1     0     1     1     0     8    0
zombiepl   144      193    0      193     2     1     1     1     0     8    1
processpl  960      222    0      193     4     0     4     4     0     8    0
procpl     624      227    0      196     3     0     3     3     0     8    0
sockpl     400       73    0       55     2     0     2     2     0     8    0
mcl4k      4096       3    0        0     1     0     1     1     0     8    0
mcl2k      2048      73    0        0     9     0     9     9     0     8    0
mtagpl      80        1    0        0     1     0     1     1     0     8    0
mbufpl     256      110    0        0     6     0     6     6     0     8    0
bufpl      280     1857    0       79   127     0   127   127     0     8    0
anonpl      16    19277    0    18009     7     1     6     7     0   124    0
amapchunkpl 152     537    0      494     2     0     2     2     0   158    0
amappl16   192       83    0       79     1     0     1     1     0     8    0
amappl15   184        1    0        0     1     0     1     1     0     8    0
amappl14   176        1    0        1     1     1     0     1     0     8    0
amappl13   168       14    0       13     2     1     1     1     0     8    0
amappl12   160        1    0        1     1     1     0     1     0     8    0
amappl11   152       69    0       51     1     0     1     1     0     8    0
amappl10   144        7    0        5     1     0     1     1     0     8    0
amappl9    136      222    0      221     1     0     1     1     0     8    0
amappl8    128      239    0      236     1     0     1     1     0     8    0
amappl7    120       92    0       84     1     0     1     1     0     8    0
amappl6    112       15    0       15     2     1     1     1     0     8    1
amappl5    104      161    0      146     1     0     1     1     0     8    0
amappl4     96      482    0      454     1     0     1     1     0     8    0
amappl3     88       96    0       90     1     0     1     1     0     8    0
amappl2     80      825    0      765     3     1     2     2     0     8    0
amappl1     72    14254    0    13826    16     6    10    16     0     8    0
amappl      80      416    0      392     1     0     1     1     0    84    0
dma4096    4096       1    0        1     1     1     0     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        1    0        0     1     0     1     1     0     8    0
uaddrrnd    24      207    0      193     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24      207    0      193     1     0     1     1     0     8    0
vmmpekpl   168     5414    0     5391     2     0     2     2     0     8    0
vmmpepl    168    29336    0    28450    53    14    39    51     0   357    0
vmsppl     368      206    0      193     2     0     2     2     0     8    0
pdppl      4096     421    0      386     5     0     5     5     0     8    0
pvpl        32    79642    0    76609    31     3    28    28     0   265    1
pmappl     232      206    0      193     1     0     1     1     0     8    0
extentpl    40       46    0       29     1     0     1     1     0     8    0
phpool     112      138    0        4     4     0     4     4     0     8    0

Crashes (46771):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/02/28 07:43 openbsd c6faab6d3d04 c88c7b75 .config console log report syz C ci-openbsd-multicore
2019/12/18 20:25 openbsd bcf611cde4c3 79b211f7 .config console log report syz C ci-openbsd-setuid
2020/10/27 18:51 openbsd 969402718346 94942294 .config console log report ci-openbsd-multicore
2020/10/27 12:35 openbsd 969402718346 94942294 .config console log report ci-openbsd-multicore
2020/10/27 10:56 openbsd 969402718346 94942294 .config console log report ci-openbsd-setuid
2020/10/27 07:23 openbsd 969402718346 94942294 .config console log report ci-openbsd-multicore
2020/10/27 07:20 openbsd 969402718346 94942294 .config console log report ci-openbsd-multicore
2020/10/27 02:50 openbsd eda2c43b759c c62e79ba .config console log report ci-openbsd-setuid
2020/10/27 00:16 openbsd eda2c43b759c c62e79ba .config console log report ci-openbsd-setuid
2020/10/27 00:07 openbsd eda2c43b759c c62e79ba .config console log report ci-openbsd-multicore
2020/10/26 05:27 openbsd 5d65abadd091 a1839e81 .config console log report ci-openbsd-setuid
2020/10/23 19:31 openbsd beaa7c7f1dda 2bb6666c .config console log report ci-openbsd-setuid
2020/10/22 18:52 openbsd 15bd22bd61f4 be6b1582 .config console log report ci-openbsd-multicore
2020/10/22 05:26 openbsd 0415c54721ce be6b1582 .config console log report ci-openbsd-setuid
2020/10/21 20:20 openbsd 503f91b4c7f3 e761439e .config console log report ci-openbsd-setuid
2020/10/20 11:44 openbsd 81b11609be1d ff4a3345 .config console log report ci-openbsd-multicore
2020/10/19 01:05 openbsd 81b11609be1d fea47c01 .config console log report ci-openbsd-setuid
2020/10/18 11:00 openbsd 81b11609be1d fea47c01 .config console log report ci-openbsd-setuid
2020/10/18 09:33 openbsd 81b11609be1d fea47c01 .config console log report ci-openbsd-setuid
2020/10/17 04:16 openbsd 81b11609be1d 6e262c73 .config console log report ci-openbsd-setuid
2020/10/16 21:09 openbsd 81b11609be1d 6e262c73 .config console log report ci-openbsd-setuid
2020/10/15 20:56 openbsd 81b11609be1d 6e262c73 .config console log report ci-openbsd-multicore
2020/10/15 07:42 openbsd 354e02d3863e fc7735a2 .config console log report ci-openbsd-multicore
2020/10/13 14:31 openbsd 87afc19ed925 bd69ee0d .config console log report ci-openbsd-multicore
2020/10/12 14:04 openbsd 0d27d3d93b84 4a77ae0b .config console log report ci-openbsd-setuid
2020/10/11 12:17 openbsd 0f5570612629 4a77ae0b .config console log report ci-openbsd-setuid
2020/10/10 14:18 openbsd 16c91a581570 b74c49a6 .config console log report ci-openbsd-multicore
2020/10/08 14:59 openbsd 64269a64f3c1 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/08 09:43 openbsd 64269a64f3c1 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/08 07:30 openbsd f46e9419ce46 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 18:42 openbsd b015073fd67e 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/07 15:45 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 14:30 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 12:35 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/07 12:23 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 09:32 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/07 07:47 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/07 07:37 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 05:53 openbsd 7392f8b916e4 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 04:06 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/07 04:03 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/07 03:01 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-setuid
2020/10/07 01:36 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/06 23:37 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/06 23:21 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/06 22:05 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2020/10/06 20:19 openbsd 00b2210f7cb0 1880b4a9 .config console log report ci-openbsd-multicore
2019/12/18 19:23 openbsd bcf611cde4c3 79b211f7 .config console log report ci-openbsd-setuid
* Struck through repros no longer work on HEAD.