On Tue, Apr 15, 2014 at 7:13 AM, Kenneth Westerback
<kwesterb...@gmail.com> wrote:
> On 15 April 2014 08:34, Otto Moerbeek <o...@drijf.net> wrote:
>> On Mon, Apr 14, 2014 at 09:32:43PM -0400, sven falempin wrote:
>>
>>> so i got gdb back to the machine because i cannot reproduce outside of the 
>>> box.
>>> gdb too old cannot gcore.
>>>
>>> The state is nasty, but i do get the trace of the dhcp transaction.
>>>
>>> [..]
>>> DHCPREQUEST on trunk0 to 255.255.255.255 port 67
>>> DHCPACK from 10.0.0.254 (96:4f:87:9c:ad:67)
>>>
>>> Program received signal SIGSEGV, Segmentation fault.
>>> 0x1c005b26 in add_classless_static_routes (rdomain=13684944,
>>> classless_static_routes=0x0) at /usr/src/sbin/dhclient/dhclient.c:2408
>>> 2408    /usr/src/sbin/dhclient/dhclient.c: No such file or directory.
>>>         in /usr/src/sbin/dhclient/dhclient.c
>>> (gdb) bt
>>> #0  0x1c005b26 in add_classless_static_routes (rdomain=13684944,
>>> classless_static_routes=0x0) at /usr/src/sbin/dhclient/dhclient.c:2408
>>> #1  0xd0d0d0d0 in ?? ()
>>> #2  0x00d0d0d0 in ?? ()
>>> #3  0x00000000 in ?? ()
>>
>> ... the line in 5.4 is :
>>
>> 2405:           i += bytes;
>> 2406:
>> 2407:           memset(&gateway, 0, sizeof(gateway));
>> 2408:           memcpy(&gateway, &classless_static_routes->data[i], 4);
>>
>> The memcpy segfaults.
>
> Not surprising *if* the gdb info is correct and the pointer parameter
> 'classless_static_routes' is NULL. :-)
>
>> Current and 5.5 have a rewritten version of this code.
>> Can you reproduce on current?
>
> That would be good to check, but if there a NULL pointer being passed
> I fear it will still fault.
>
>>
>>         -Otto
>>
>
> [snip]
>
>>>
>>> 1397524674.011308 96:4f:87:9c:ad:67 fe:e1:ba:d0:8e:d0 0800 373:
>>> 10.0.0.254.67 > 10.0.0.126.68: xid:0x95ce17 Y:10.0.0.126 S:10.0.0.254
>>> vend-rfc1048 DHCP:ACK SID:10.0.0.254 LT:43200 RN:21600 RB:37800
>>> SM:255.255.255.0 BR:10.0.0.255 HN:"ulis-v12-GW"
>>> T121:415279105,3232236030,415279114,3232236030,3232236030,167772414
>>> NS:10.0.0.254 DG:10.0.0.254 (DF)
>>>   0000: fee1 bad0 8ed0 964f 879c ad67 0800 4500  .......O...g..E.
>>>   0010: 0167 0000 4000 4011 240b 0a00 00fe 0a00  .g..@.@.$.......
>>>   0020: 007e 0043 0044 0153 9aa6 0201 0600 0095  .~.C.D.S........
>>>   0030: ce17 0000 0000 0000 0000 0a00 007e 0a00  .............~..
>>>   0040: 00fe 0000 0000 fee1 bad0 8ed0 0000 0000  ................
>>>   0050: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   0060: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   0070: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   0080: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   0090: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   00a0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   00b0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   00c0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   00d0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   00e0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   00f0: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   0100: 0000 0000 0000 0000 0000 0000 0000 0000  ................
>>>   0110: 0000 0000 0000 6382 5363 3501 0536 040a  ......c.Sc5..6..
>>>   0120: 0000 fe33 0400 00a8 c03a 0400 0054 603b  ...3.....:...T`;
>>>   0130: 0400 0093 a801 04ff ffff 001c 040a 0000  ................
>>>   0140: ff0c 0b75 6c69 732d 7631 322d 4757 7918  ...ulis-v12-GWy.
>>>   0150: 18c0 a801 c0a8 01fe 18c0 a80a c0a8 01fe  ................
>>>   0160: c0a8 01fe 0a00 00fe 0604 0a00 00fe 0304  ................
>>>   0170: 0a00 00fe ff                             .....
>>
>
> Pulling out the options provided we get
>
> Options
> =======
>
> 6382 5363 /* Cookie */
> 35 01 05           /* DHCP message type */
> 36 04 0a 00 00 fe  /* DHCP server id */
> 33 04 00 00 a8 c0  /* DHCP lease time */
> 3a 04 00 00 54 60  /* DHCP renewal time */
> 3b 04 00 00 93 a8  /* DHCP rebinding time */
> 01 04 ff ff ff 00  /* Subnet Mask */
> 1c 04 0a 00 00 ff  /* Broadcast Address */
> 0c 0b 75 6c 69 73 2d 76 31 32 2d 47 57  /* Hostname */
> 79 18 18 c0 a8 01 c0 a8 01 fe 18 c0 a8 0a c0 a8 01 fe c0 a8 01 fe 0a
> 00 00 fe  /Classless static routes */
> 06 04 0a 00 00 fe  /* Domain Name Servers */
> 03 04 0a 00 00 fe  /* Routers */
> ff                 /* End of Options */
>
>
> And looking at the classless static routes closer we see
>
> 79 18
>       18 c0 a8 01 c0 a8 01 fe  /* 192.168.1/24 via 192.168.1.254 */
>       18 c0 a8 0a c0 a8 01 fe  /* 192.168.10/24 via 192.168.1.254 */
>       c0 a8 01 fe 0a 00 00 fe  /* ??? */
>
> Where the last one is, to use the technical term, fucked. It seems to
> specify a network with 'c0' == 192 bits. I can't see how this would
> cause
> a NULL pointer to be passed though.
>
> .... Ken

ok the last was supposed to be 192.168.1.254/32 via 10.0.0.254, in the
dhcp server but i didn't specify the subnet.

with this infos i will try to replay this on last snapshots (basic
test didnt fault)


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