syzbot


uvm_fault: frag6_input

Status: fixed on 2019/08/27 19:45
Reported-by: syzbot+0aa80b25e9041001cac8@syzkaller.appspotmail.com
Fix commit: d3f3cb99fa83 Do not use the flow of the first fragment to store ECN information. Handle the ECN in the fragment queue. Reported-by: syzbot+0aa80b25e9041001cac8@syzkaller.appspotmail.com fix from FreeBSD; OK claudio@
First crash: 1192d, last: 1188d

Sample crash report:
U.}_3}
Ū4N doJc[_X^QGRQ?8VI{1ϣ}xNI4
VFLYo%U`irwq?5FX~?OUG0[uvm_fault(0xfffffd803f014bb0, 0x24, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at      frag6_input+0x762:      movl    0x24(%rax),%r14d
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
kernel page fault
uvm_fault(0xfffffd803f014bb0, 0x24, 0, 1) -> e
frag6_input(ffff80001595fbd8,ffff80001595fbe4,2c,18) at frag6_input+0x762 sys/netinet6/frag6.c:321
end trace frame: 0xffff80001595fa60, count: 0
ddb> trace
frag6_input(ffff80001595fbd8,ffff80001595fbe4,2c,18) at frag6_input+0x762 sys/netinet6/frag6.c:321
ip_deliver(ffff80001595fbd8,ffff80001595fbe4,2c,18) at ip_deliver+0x2e3 sys/netinet/ip_input.c:665
ip6_input_if(ffff80001595fbd8,ffff80001595fbe4,29,0,ffff80000069c000) at ip6_input_if+0x153a ip6_ours sys/netinet6/ip6_input.c:518 [inline]
ip6_input_if(ffff80001595fbd8,ffff80001595fbe4,29,0,ffff80000069c000) at ip6_input_if+0x153a sys/netinet6/ip6_input.c:340
ipv6_input(ffff80000069c000,fffffd803f030a00) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171
if_input_local(ffff80000069c000,fffffd803f030a00,18) at if_input_local+0x121 sys/net/if.c:783
ip6_output(fffffd803f030b00,ffff800000a7b600,fffffd803700cd90,0,0,fffffd803700cd20) at ip6_output+0xd35
rip6_output(fffffd803f030b00,fffffd803700dc00,ffff80001595ff48,0) at rip6_output+0x4d7 sys/netinet6/raw_ip6.c:481
rip6_usrreq(fffffd803700dc00,9,fffffd803f030b00,0,0,ffff8000ffff2780) at rip6_usrreq+0x5cd sys/netinet6/raw_ip6.c:670
sosend(fffffd803700dc00,0,ffff800015960178,0,0,0) at sosend+0x660 sys/kern/uipc_socket.c:524
dofilewritev(ffff8000ffff2780,3,ffff800015960178,0,ffff800015960280) at dofilewritev+0x1ac sys/kern/sys_generic.c:364
sys_write(ffff8000ffff2780,ffff800015960218,ffff800015960280) at sys_write+0x83 sys/kern/sys_generic.c:284
syscall(ffff8000159602e0) at syscall+0x508
Xsyscall(6,0,c,0,3,44c6adc8010) at Xsyscall+0x128
end of kernel
end trace frame: 0x44f11f05980, count: -13
ddb> show registers
rdi                                0
rsi                                0
rbp               0xffff80001595f9e0
rbx                            0x600
rdx                                0
rcx                                0
rax                                0
r8                              0x30
r9                                 0
r10               0xe28e8f57f5e1be29
r11               0xadf8ce0786008f0a
r12                                0
r13               0xfffffd803ae09f48
r14               0xfffffd803ae09f58
r15               0xfffffd80384d5854
rip               0xffffffff818f50a2    frag6_input+0x762
cs                               0x8
rflags                       0x10206    __ALIGN_SIZE+0xf206
rsp               0xffff80001595f920
ss                              0x10
frag6_input+0x762:      movl    0x24(%rax),%r14d
ddb> show proc
PROC (syz-executor.0) pid=249470 stat=onproc
    flags process=0 proc=4000000<THREAD>
    pri=81, usrpri=81, nice=20
    forw=0xffffffffffffffff, list=0xffff8000ffff2018,0xffffffff8257f9f0
    process=0xffff8000ffff6010 user=0xffff80001595b000, vmspace=0xfffffd803f014bb0
    estcpu=36, cpticks=1, pctcpu=0.0
    user=0, sys=1, intr=0
ddb> ps
   PID     TID   PPID    UID  S       FLAGS  WAIT          COMMAND
 76487  188346  41014      0  2           0                syz-executor.0
*76487  249470  41014      0  7   0x4000000                syz-executor.0
 41014  427001  21361      0  3        0x82  nanosleep     syz-executor.0
 36105  513958  21361      0  2         0x2                syz-executor.1
  2651  142318      1      0  3    0x100083  ttyin         getty
 24981  405467      0      0  3     0x14200  bored         sosplice
 21361  177485   9827      0  3        0x82  thrsleep      syz-fuzzer
 21361  223992   9827      0  3   0x4000082  nanosleep     syz-fuzzer
 21361  510920   9827      0  3   0x4000082  kqread        syz-fuzzer
 21361   32621   9827      0  3   0x4000082  thrsleep      syz-fuzzer
 21361  173659   9827      0  3   0x4000082  thrsleep      syz-fuzzer
 21361  323559   9827      0  3   0x4000082  thrsleep      syz-fuzzer
 21361  159439   9827      0  3   0x4000082  thrsleep      syz-fuzzer
 21361  162042   9827      0  3   0x4000082  thrsleep      syz-fuzzer
  9827  396414  45460      0  3    0x10008a  pause         ksh
 45460  289121   7664      0  3        0x92  select        sshd
  7664  179011      1      0  3        0x80  select        sshd
 40052  344904  45680     73  3    0x100090  kqread        syslogd
 45680   50392      1      0  3    0x100082  netio         syslogd
 94323   27640      0      0  2     0x14200                zerothread
 30017  511305      0      0  3     0x14200  aiodoned      aiodoned
 70985  336814      0      0  3     0x14200  syncer        update
 43074  522888      0      0  3     0x14200  cleaner       cleaner
 11624  415219      0      0  3     0x14200  reaper        reaper
 69014  299881      0      0  3     0x14200  pgdaemon      pagedaemon
 19716  134680      0      0  3     0x14200  bored         crynlk
 75950   54693      0      0  3     0x14200  bored         crypto
 63219   71791      0      0  3  0x40014200  acpi0         acpi0
 51206   77277      0      0  3     0x14200  bored         softnet
 28969  210923      0      0  3     0x14200  bored         systqmp
 51389  510916      0      0  3     0x14200  bored         systq
 80573  253878      0      0  3  0x40014200  bored         softclock
 31048  291924      0      0  3  0x40014200                idle0
 37551   82460      0      0  3     0x14200  bored         smr
     1  228747      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  9574   6332K   14912K  78643K     42728        0        0
            pcb    14      8K       8K  78643K      1392        0        0
         rtable   116      4K       5K  78643K      2617        0        0
         ifaddr    79     22K      26K  78643K      1201        0        0
       counters    19     16K      16K  78643K        19        0        0
       ioctlops     0      0K       2K  78643K       723        0        0
            iov     0      0K      32K  78643K      1376        0        0
          mount     1      1K       1K  78643K         1        0        0
         vnodes  1190     75K      77K  78643K     13113        0        0
      UFS quota     1     32K      32K  78643K         1        0        0
      UFS mount     5     36K      36K  78643K         5        0        0
            shm     2      1K       9K  78643K       177        0        0
         VM map     2      0K       0K  78643K        16        0        0
            sem    12      0K       0K  78643K      1362        0        0
        dirhash    12      2K       2K  78643K        12        0        0
           ACPI  1793    195K     288K  78643K     12645        0        0
      file desc     5     13K      25K  78643K     12740        0        0
          sigio     0      0K       0K  78643K       175        0        0
           proc    42     30K      54K  78643K      3284        0        0
        subproc    32      2K       2K  78643K       711        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      1142        0        0
       in_multi    33      2K       2K  78643K       818        0        0
    ether_multi     1      0K       0K  78643K        49        0        0
            mrt     2      0K       0K  78643K        32        0        0
    ISOFS mount     1     32K      32K  78643K         1        0        0
  MSDOSFS mount     1     16K      16K  78643K         1        0        0
           ttys   120    530K     530K  78643K       120        0        0
           exec     0      0K       1K  78643K      1977        0        0
     pfkey data     0      0K       0K  78643K         6        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   118     22K      32K  78643K     30957        0        0
       UVM aobj   130      5K       5K  78643K       146        0        0
        memdesc     1      4K       4K  78643K         1        0        0
    crypto data     1      1K       1K  78643K         1        0        0
    ip6_options     2      0K       1K  78643K      1444        0        0
            NDP    19      0K       0K  78643K       379        0        0
           temp   220   3536K    4176K  78643K    221875        0        0
         kqueue     0      0K       0K  78643K       122        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       86    0       80     1     0     1     1     0     8    0
rtpcb       80      559    0      559    12    11     1     1     0     8    1
rtentry    112      494    0      449     2     0     2     2     0     8    0
unpcb      120     4451    0     4445     1     0     1     1     0     8    0
syncache   264        4    0        4     1     1     0     1     0     8    0
sackhl      24        1    0        1     1     1     0     1     0     8    0
tcpqe       32     1337    0     1337     1     1     0     1     0     8    0
tcpcb      544     2331    0     2326     1     0     1     1     0     8    0
ipq         40       18    0       18     6     5     1     1     0     8    1
ipqe        40       42    0       42     6     5     1     1     0     8    1
inpcb      280     6853    0     6848     6     5     1     2     0     8    0
ip6q        72        6    0        5     4     3     1     1     0     8    0
ip6af       48        9    0        8     3     2     1     1     0     8    0
nd6         48      123    0      117     1     0     1     1     0     8    0
pkpcb       40       53    0       53    19    19     0     1     0     8    0
swfcl       56        7    0        0     1     0     1     1     0     8    0
ppxss      1128     191    0      191    42    41     1     1     0     8    1
art_heap8  4096       1    0        0     1     0     1     1     0     8    0
art_heap4  256     1991    0     1793    19     6    13    13     0     8    0
art_table   32     1992    0     1793     2     0     2     2     0     8    0
art_node    16      476    0      436     1     0     1     1     0     8    0
sysvmsgpl   40       34    0       30     1     0     1     1     0     8    0
semupl     112        1    0        1     1     1     0     1     0     8    0
semapl     112     1360    0     1350     1     0     1     1     0     8    0
shmpl      112      144    0       16     4     0     4     4     0     8    0
dirhash    1024      17    0        0     3     0     3     3     0     8    0
dino1pl    128    21310    0    19890    46     0    46    46     0     8    0
ffsino     240    21310    0    19890    84     0    84    84     0     8    0
nchpl      144    39049    0    37422    61     0    61    61     0     8    0
uvmvnodes   72     7989    0        0   146     0   146   146     0     8    0
vnodes     200     7989    0        0   421     0   421   421     0     8    0
namei      1024  129552    0   129552     7     6     1     1     0     8    1
vmpool     520       14    0       14     7     7     0     1     0     8    0
scsiplug    64       22    0       22    15    15     0     1     0     8    0
scxspl     192   123936    0   123936    46    44     2     7     0     8    2
plimitpl   152     1209    0     1203     1     0     1     1     0     8    0
sigapl     432    12804    0    12793     2     0     2     2     0     8    0
futexpl     56   212951    0   212951     9     8     1     1     0     8    1
knotepl    112     3100    0     3081     2     1     1     2     0     8    0
kqueuepl   104     2917    0     2915     1     0     1     1     0     8    0
pipepl     112     7406    0     7387    15    14     1     2     0     8    0
fdescpl    424    12805    0    12793     2     0     2     2     0     8    0
filepl     120    77836    0    77751    29    25     4     5     0     8    1
lockfpl    104     4552    0     4552    11    10     1     1     0     8    1
lockfspl    48     1500    0     1500    11    10     1     1     0     8    1
sessionpl  112       66    0       58     1     0     1     1     0     8    0
pgrppl      48      222    0      214     1     0     1     1     0     8    0
ucredpl     96    15038    0    15032     1     0     1     1     0     8    0
zombiepl   144    12797    0    12797     2     1     1     1     0     8    1
processpl  864    12824    0    12797     4     0     4     4     0     8    0
procpl     632    28201    0    28166     5     1     4     5     0     8    0
sosppl     128      133    0      133    34    33     1     1     0     8    1
sockpl     384    12087    0    12076    18    16     2     4     0     8    0
mcl64k     65536   3183    0     3183   305   296     9    33     0     8    9
mcl16k     16384     67    0       67    33    33     0     1     0     8    0
mcl12k     12288    254    0      254    37    37     0     1     0     8    0
mcl9k      9216     150    0      150    42    42     0     1     0     8    0
mcl8k      8192     232    0      232    39    38     1     1     0     8    1
mcl4k      4096     652    0      652    17    16     1     1     0     8    1
mcl2k2     2112      85    0       85    34    34     0     1     0     8    0
mcl2k      2048   79415    0    79363    31    24     7    14     0     8    0
mtagpl      80      375    0      371     3     2     1     1     0     8    0
mbufpl     256   189650    0   189549   150   142     8    24     0     8    0
bufpl      256    39439    0    31432   501     0   501   501     0     8    0
anonpl      16  1144457    0  1132179   340   281    59   101     0    62    0
amapchunkpl 152   54775    0    54646    91    84     7    35     0   158    0
amappl16   192    64897    0    64211   374   334    40    47     0     8    5
amappl15   184     3066    0     3066     5     5     0     1     0     8    0
amappl14   176     3575    0     3568     1     0     1     1     0     8    0
amappl13   168      674    0      674     9     9     0     1     0     8    0
amappl12   160     2112    0     2106     1     0     1     1     0     8    0
amappl11   152     1505    0     1501     1     0     1     1     0     8    0
amappl10   144     2086    0     2082     1     0     1     1     0     8    0
amappl9    136     2618    0     2612     1     0     1     1     0     8    0
amappl8    128     2065    0     2027     2     0     2     2     0     8    0
amappl7    120     2116    0     2111     1     0     1     1     0     8    0
amappl6    112     1424    0     1416     1     0     1     1     0     8    0
amappl5    104     2566    0     2559     1     0     1     1     0     8    0
amappl4     96    11396    0    11372     1     0     1     1     0     8    0
amappl3     88     5630    0     5619     1     0     1     1     0     8    0
amappl2     80   100648    0   100586     3     1     2     3     0     8    0
amappl1     72   230817    0   230445    25    16     9    19     0     8    0
amappl      80    29095    0    29055     3     1     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
dma64       64      259    0      259     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      145    0       16     3     0     3     3     0     8    0
uaddrrnd    24    12819    0    12793     1     0     1     1     0     8    0
uaddrbest   32        2    0        0     1     0     1     1     0     8    0
uaddr       24    12819    0    12793     1     0     1     1     0     8    0
vmmpekpl   168    78795    0    78765     2     0     2     2     0     8    0
vmmpepl    168  1490198    0  1488520   541   448    93   108     0   357   12
vmsppl     272    12804    0    12793     5     4     1     2     0     8    0
pdppl      4096   25644    0    25614     6     1     5     6     0     8    0
pvpl        32  3231614    0  3216290   816   672   144   335     0   265    8
pmappl     200    12818    0    12807     1     0     1     1     0     8    0
extentpl    40       41    0       26     1     0     1     1     0     8    0
phpool     112     1204    0      568    20     0    20    20     0     8    0

Crashes (24):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-openbsd-main 2019/08/27 04:38 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/27 02:54 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/27 01:42 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/26 23:29 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/26 19:03 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/26 16:24 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/26 15:42 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/26 14:52 openbsd 4350d62ed76b d21c5d9d .config log report
ci-openbsd-main 2019/08/26 08:24 openbsd 56a8f046bf24 d21c5d9d .config log report
ci-openbsd-main 2019/08/26 06:40 openbsd 56a8f046bf24 d21c5d9d .config log report
ci-openbsd-main 2019/08/26 01:31 openbsd 56a8f046bf24 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 23:37 openbsd 56a8f046bf24 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 16:00 openbsd a1d6d12691b4 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 13:38 openbsd a1d6d12691b4 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 04:58 openbsd 1507cfe1d6a4 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 01:26 openbsd 1507cfe1d6a4 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 01:00 openbsd 1507cfe1d6a4 d21c5d9d .config log report
ci-openbsd-main 2019/08/25 00:09 openbsd 1507cfe1d6a4 d21c5d9d .config log report
ci-openbsd-main 2019/08/24 20:17 openbsd 1507cfe1d6a4 78ded196 .config log report
ci-openbsd-main 2019/08/24 19:20 openbsd 1507cfe1d6a4 78ded196 .config log report
ci-openbsd-main 2019/08/24 02:38 openbsd 9be55947e891 78ded196 .config log report
ci-openbsd-main 2019/08/24 02:30 openbsd 9be55947e891 78ded196 .config log report
ci-openbsd-main 2019/08/23 09:34 openbsd 9f57e42b5520 ca6f3cfa .config log report
ci-openbsd-main 2019/08/23 06:20 openbsd 9f57e42b5520 ca6f3cfa .config log report
* Struck through repros no longer work on HEAD.