syzbot


uvm_fault: m_zero

Status: auto-closed as invalid on 2020/02/04 11:13
Reported-by: syzbot+e8846a7649e5b067fa4f@syzkaller.appspotmail.com
First crash: 1845d, last: 1845d

Sample crash report:
uvm_fault(0xffffffff824fee30, 0xffffffff815e1e34, 0, 2) -> e
kernel: page fault trap, code=0
Stopped at      m_zero+0xde:    orb     $0x20,0x1f(%r15)
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
kernel page fault
uvm_fault(0xffffffff824fee30, 0xffffffff815e1e34, 0, 2) -> e
m_zero(fffffd802cf60000) at m_zero+0xde sys/kern/uipc_mbuf.c:1301
end trace frame: 0xffff800014b41fd0, count: 0
ddb> trace
m_zero(fffffd802cf60000) at m_zero+0xde sys/kern/uipc_mbuf.c:1301
m_free(fffffd802cf60000) at m_free+0x87 sys/kern/uipc_mbuf.c:443
ml_purge(ffff800014b42028) at ml_purge+0x50 m_freem sys/kern/uipc_mbuf.c:538 [inline]
ml_purge(ffff800014b42028) at ml_purge+0x50 sys/kern/uipc_mbuf.c:1628
ifq_purge(ffff800000cbb260) at ifq_purge+0x97 sys/net/ifq.c:423
if_down(ffff800000cbb000) at if_down+0x9c if_linkstate sys/net/if.c:1633 [inline]
if_down(ffff800000cbb000) at if_down+0x9c sys/net/if.c:1584
if_clone_destroy(ffff800014b42460) at if_clone_destroy+0x11c sys/net/if.c:1261
ifioctl(fffffd8036ff0000,80206979,ffff800014b42460,ffff8000ffff3650) at ifioctl+0x3d4 sys/net/if.c:1877
fifo_ioctl(ffff800014b422a8) at fifo_ioctl+0x101 sys/miscfs/fifofs/fifo_vnops.c:282
VOP_IOCTL(fffffd803b164ea8,80206979,ffff800014b42460,82,fffffd803f7c6ae0,ffff8000ffff3650) at VOP_IOCTL+0x88 sys/kern/vfs_vops.c:291
vn_ioctl(fffffd8037551a50,80206979,ffff800014b42460,ffff8000ffff3650) at vn_ioctl+0xb7 sys/kern/vfs_vnops.c:536
sys_ioctl(ffff8000ffff3650,ffff800014b42578,ffff800014b425c0) at sys_ioctl+0x5b9
syscall(ffff800014b42640) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555
Xsyscall(6,0,ffffffffffffff36,0,3,7412c46d010) at Xsyscall+0x128
end of kernel
end trace frame: 0x7440989d9b0, count: -13
ddb> show registers
rdi               0xffffffff81690b8e    m_zero+0xde
rsi                            0x36c
rbp               0xffff800014b41f80
rbx               0xffff800014b42460
rdx                            0x36d
rcx               0xffff800015988000
rax               0xffff800015988000
r8                 0x101010101010101
r9                0x8080808080808080
r10               0xe454091e443a2e14
r11               0xd5cf85802163dd48
r12                           0x2000    __ALIGN_SIZE+0x1000
r13                              0x3
r14               0xfffffd802cf60000
r15               0xffffffff815e1e15    lapic_delay+0xb5
rip               0xffffffff81690b8e    m_zero+0xde
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff800014b41f50
ss                              0x10
m_zero+0xde:    orb     $0x20,0x1f(%r15)
ddb> show proc
PROC (syz-executor.1) pid=18571 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=86, usrpri=86, nice=20
    forw=0xffffffffffffffff, list=0xffff8000ffff3b40,0xffff8000ffff38d8
    process=0xffff8000148a2018 user=0xffff800014b3d000, vmspace=0xfffffd803f013550
    estcpu=36, cpticks=5, pctcpu=0.0
    user=0, sys=0, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 55106  201242  15521      0  2           0                syz-executor.1
*55106   18571  15521      0  7   0x4000000                syz-executor.1
 55106  467724  15521      0  3   0x4000080  fsleep        syz-executor.1
 72227   31556  34363      0  3        0x80  nanosleep     syz-executor.0
 72227  345635  34363      0  3   0x4000080  nanosleep     syz-executor.0
 72227  373350  34363      0  3   0x4000080  fsleep        syz-executor.0
 34363  475767  69722      0  3        0x82  nanosleep     syz-executor.0
 15521   55661  69722      0  3        0x82  nanosleep     syz-executor.1
 99660  355305      0      0  3     0x14200  acct          acct
 93552  458672      0      0  3     0x14200  bored         sosplice
 69722  332178  57402      0  3        0x82  thrsleep      syz-fuzzer
 69722  375054  57402      0  3   0x4000082  thrsleep      syz-fuzzer
 69722  350397  57402      0  3   0x4000082  thrsleep      syz-fuzzer
 69722  204547  57402      0  3   0x4000082  thrsleep      syz-fuzzer
 69722  265234  57402      0  3   0x4000082  thrsleep      syz-fuzzer
 69722  170963  57402      0  3   0x4000082  thrsleep      syz-fuzzer
 69722  437066  57402      0  3   0x4000082  thrsleep      syz-fuzzer
 69722  225696  57402      0  3   0x4000082  kqread        syz-fuzzer
 57402  328046  55003      0  3    0x10008a  pause         ksh
 55003  169174  32342      0  3        0x92  select        sshd
 17589   32593      1      0  3    0x100083  ttyin         getty
 32342  362606      1      0  3        0x80  select        sshd
  6892  498596  30172     73  3    0x100090  kqread        syslogd
 30172  130652      1      0  3    0x100082  netio         syslogd
 86056  314379      0      0  2     0x14200                zerothread
 72006  265275      0      0  3     0x14200  aiodoned      aiodoned
 27436   24010      0      0  3     0x14200  syncer        update
 25091  486315      0      0  3     0x14200  cleaner       cleaner
 84380   77799      0      0  3     0x14200  reaper        reaper
 36423  466907      0      0  3     0x14200  pgdaemon      pagedaemon
 24605  126644      0      0  3     0x14200  bored         crynlk
 20580  219869      0      0  3     0x14200  bored         crypto
 60850  143387      0      0  3  0x40014200  acpi0         acpi0
 21331  410425      0      0  3     0x14200  bored         softnet
 21776  479307      0      0  3     0x14200  bored         systqmp
 68476   54793      0      0  3     0x14200  bored         systq
 33482  450491      0      0  3  0x40014200  bored         softclock
 81924  491279      0      0  3  0x40014200                idle0
 12411    6111      0      0  3     0x14200  bored         smr
     1  285948      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 Kern Lim
         devbuf  9553   6367K   13164K  78643K     36376        0        0
            pcb    13     11K      13K  78643K       972        0        0
         rtable   150     14K      15K  78643K      1812        0        0
         ifaddr    89     19K      20K  78643K       508        0        0
       counters    19     16K      16K  78643K        19        0        0
       ioctlops     0      0K       2K  78643K       226        0        0
            iov     0      0K      32K  78643K      1086        0        0
          mount     1      1K       1K  78643K         1        0        0
         vnodes  1330     83K      84K  78643K      8120        0        0
      UFS quota     1     32K      32K  78643K         1        0        0
      UFS mount     5     36K      36K  78643K         5        0        0
            shm     2      1K       5K  78643K        56        0        0
         VM map    38      9K       9K  78643K        51        0        0
            sem    12      0K       0K  78643K      1163        0        0
        dirhash    12      2K       2K  78643K        12        0        0
           ACPI  1793    195K     288K  78643K     12645        0        0
      file desc     6     17K      25K  78643K      2736        0        0
          sigio     0      0K       0K  78643K        40        0        0
           proc    44     30K      63K  78643K      1476        0        0
        subproc    32      2K       2K  78643K       391        0        0
    NFS srvsock     1      0K       0K  78643K         1        0        0
     NFS daemon     1     16K      16K  78643K         1        0        0
    ip_moptions     0      0K       0K  78643K       225        0        0
       in_multi    36      2K       2K  78643K       336        0        0
    ether_multi     1      0K       0K  78643K        26        0        0
            mrt     1      0K       0K  78643K        28        0        0
    ISOFS mount     1     32K      32K  78643K         1        0        0
  MSDOSFS mount     1     16K      16K  78643K         1        0        0
           ttys    84    371K     371K  78643K        84        0        0
           exec     0      0K       1K  78643K       741        0        0
     pfkey data     0      0K       0K  78643K         2        0        0
        pagedep     1      8K       8K  78643K         1        0        0
       inodedep     1     32K      32K  78643K         1        0        0
         newblk     1      0K       0K  78643K         1        0        0
        VM swap     7     26K      26K  78643K         7        0        0
       UVM amap   170    299K     300K  78643K      8030        0        0
       UVM aobj   130      4K       4K  78643K       149        0        0
        memdesc     1      4K       4K  78643K         1        0        0
    crypto data     1      1K       1K  78643K         1        0        0
    ip6_options     0      0K       0K  78643K       567        0        0
            NDP    18      0K       0K  78643K       159        0        0
           temp   215   3548K    4182K  78643K     56287        0        0
         kqueue     0      0K       0K  78643K        16        0        0
      SYN cache     2     16K      16K  78643K         2        0        0
ddb> show all pools
Name      Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
arp         64       41    0       37     1     0     1     1     0     8    0
rtpcb       80      289    0      289     1     0     1     1     0     8    1
rtentry    112      336    0      277     2     0     2     2     0     8    0
unpcb      120     1848    0     1836     2     1     1     2     0     8    0
syncache   264       22    0       22     7     7     0     1     0     8    0
sackhl      24        1    0        1     1     1     0     1     0     8    0
tcpqe       32      129    0      129     4     4     0     1     0     8    0
tcpcb      544     1168    0     1164    14    13     1    12     0     8    0
ipq         40       35    0       35    12    11     1     1     0     8    1
ipqe        40      896    0      896    12    11     1     1     0     8    1
inpcb      280     5726    0     5722    17    15     2     9     0     8    1
rttmr       72       12    0       11     4     3     1     1     0     8    0
nd6         48       49    0       46     3     2     1     1     0     8    0
pkpcb       40        4    0        4     2     2     0     1     0     8    0
ppxss      1128      48    0       48    10    10     0     1     0     8    0
art_heap8  4096       9    0        5     6     2     4     6     0     8    0
art_heap4  256     1422    0     1150    29    11    18    20     0     8    0
art_table   32     1431    0     1155     6     3     3     3     0     8    0
art_node    16      330    0      285     1     0     1     1     0     8    0
sysvmsgpl   40       56    0       36     1     0     1     1     0     8    0
semapl     112     1161    0     1151     1     0     1     1     0     8    0
shmpl      112      147    0       19     4     0     4     4     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino1pl    128     5512    0     4113    46     0    46    46     0     8    0
ffsino     240     5512    0     4113    83     0    83    83     0     8    0
nchpl      144     9620    0     9157    60    40    20    60     0     8    0
uvmvnodes   72     6750    0        0   123     0   123   123     0     8    0
vnodes     208     6750    0        0   356     0   356   356     0     8    0
namei      1024   39001    0    39001     3     2     1     1     0     8    1
vcpupl     1984      36    0        0     5     0     5     5     0     8    0
vmpool     520       49    0       13     4     1     3     3     0     8    0
scsiplug    64        1    0        1     1     1     0     1     0     8    0
scxspl     192    32583    0    32583    20    19     1     7     0     8    1
plimitpl   152      237    0      231     1     0     1     1     0     8    0
sigapl     432     2843    0     2831     2     0     2     2     0     8    0
futexpl     56   102359    0   102357     3     2     1     1     0     8    0
knotepl    112      694    0      670     1     0     1     1     0     8    0
kqueuepl   104      928    0      924     4     3     1     4     0     8    0
pipepl     112     1858    0     1839     8     6     2     2     0     8    1
fdescpl    424     2844    0     2831     2     0     2     2     0     8    0
filepl     120    31159    0    31064    30    25     5    10     0     8    2
lockfpl    104     1463    0     1463     1     0     1     1     0     8    1
lockfspl    48      413    0      413     1     0     1     1     0     8    1
sessionpl  112       38    0       30     1     0     1     1     0     8    0
pgrppl      48       67    0       59     1     0     1     1     0     8    0
ucredpl     96     2556    0     2550     1     0     1     1     0     8    0
zombiepl   144     2831    0     2831     1     0     1     1     0     8    1
processpl  864     2860    0     2831     4     0     4     4     0     8    0
procpl     632     6139    0     6099     4     0     4     4     0     8    0
sosppl     128       45    0       45     9     8     1     1     0     8    1
sockpl     384     8005    0     7988    29    25     4    14     0     8    1
mcl64k     65536   1176    0     1176    95    94     1    33     0     8    1
mcl16k     16384     52    0       52     9     8     1     1     0     8    1
mcl12k     12288    160    0      160     4     3     1     1     0     8    1
mcl9k      9216      53    0       53     9     8     1     1     0     8    1
mcl8k      8192     161    0      161     4     3     1     1     0     8    1
mcl4k      4096     300    0      300     6     5     1     1     0     8    1
mcl2k2     2112      23    0       23     7     7     0     1     0     8    0
mcl2k      2048   75909    0    75864    20    13     7    15     0     8    0
mtagpl      80      124    0      103     5     4     1     1     0     8    0
mbufpl     256   152471    0   152328   119   103    16    34     0     8    5
bufpl      256    17375    0    10624   423     0   423   423     0     8    0
anonpl      16   460708    0   440263   160    67    93    99     0    62    8
amapchunkpl 152   18591    0    18435    68    56    12    17     0   158    5
amappl16   192    19257    0    18101   161   102    59    69     0     8    1
amappl15   184       63    0       63     2     2     0     1     0     8    0
amappl14   176      700    0      693     1     0     1     1     0     8    0
amappl13   168      552    0      550     1     0     1     1     0     8    0
amappl12   160      293    0      292     4     3     1     1     0     8    0
amappl11   152      112    0      107     1     0     1     1     0     8    0
amappl10   144      658    0      654     1     0     1     1     0     8    0
amappl9    136     1191    0     1187     1     0     1     1     0     8    0
amappl8    128      769    0      717     2     0     2     2     0     8    0
amappl7    120      765    0      757     1     0     1     1     0     8    0
amappl6    112       82    0       70     1     0     1     1     0     8    0
amappl5    104      771    0      763     1     0     1     1     0     8    0
amappl4     96     3280    0     3250     1     0     1     1     0     8    0
amappl3     88     1095    0     1086     1     0     1     1     0     8    0
amappl2     80    20768    0    20700     3     1     2     3     0     8    0
amappl1     72    62984    0    62577    25    16     9    20     0     8    0
amappl      80     6783    0     6719     2     0     2     2     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       17    0       17     1     1     0     1     0     8    0
aobjpl      64      148    0       19     3     0     3     3     0     8    0
uaddrrnd    24     2893    0     2831     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24     2893    0     2831     1     0     1     1     0     8    0
vmmpekpl   168    21764    0    21726     2     0     2     2     0     8    0
vmmpepl    168   362811    0   360458   256   137   119   176     0   357    9
vmsppl     272     2843    0     2831     3     2     1     2     0     8    0
pdppl      4096    5792    0     5724    13     3    10    10     0     8    1
pvpl        32  1133927    0  1109731   450   123   327   333     0   265  131
pmappl     200     2892    0     2844     3     0     3     3     0     8    0
extentpl    40       41    0       26     1     0     1     1     0     8    0
phpool     112      832    0      261    18     0    18    18     0     8    0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/06 11:12 openbsd 38dc29e6b4c8 bc2c6e45 .config console log report ci-openbsd-main
* Struck through repros no longer work on HEAD.