Re: ipq_get_packet receives proper TCP and IP headers but the rest of payload is junk

Checked TSO, and it turns out it is disabled at startup. 
I'm really
stumped on this one.



Nick

On 7/6/07, Patrick McHardy <kabertrash.net> wrote:
> Nick Landry wrote:
> > Thanks, I checked that but the issue is that I am
sending the exact
> > same GET request (Accept-Encoding is the same as
well) for when the
> > message passes through any of the machines.  The
read from ip_queue
> > for one machine is headers + ascii which is what
I'd expect.  The
> > other machine outputs headers + junk.
> >
> > Here's a hex dump for the machine that isn't
working (payload length
> > is 1500 bytes but I'll only print a small part):
> >
> > -->  45 00 05 78 02 37 40 00 42 06 18 5b 0a b3
00 0c
> > -->  0a 2b 04 05 c5 3a 00 50 26 a2 08 34 a8 d5
7c f7
> > -->  80 10 4f b0 de f3 00 00 08 0a e4 eb 14 02
d5 6e
> > -->  e4 1c 00 00 08 00 01 00 06 00 0f f7 b5 9b
00 00
> > -->  00 00 00 00 00 00 00 00 30 00 00 00 00 00
00 00
> > -->  45 00 00 30 bf 76 40 00 7c 06 d4 35 0a b1
2c 0f
> > -->  0a b3 29 a9 13 4b 01 bd 29 7a 9e 75 00 00
00 00
> > -->  70 02 40 00 fb 0b 00 00 02 04 05 b4 01 01
04 02
> > -->  01 01 04 02 00 15 17 29 49 62 08 00 45 08
00 34
> > -->  64 1b 40 00 40 06 be 0d 0a 2a 02 21 0a 2a
02 1f
> > -->  80 03 bb 06 8c bc 41 58 79 bb 93 af 80 10
80 00
> > -->  62 96 00 00 01 01 08 0a 00 2d 7d cc 19 d0
cd 3f
> > -->  b1 18 40 00 7e 00 40 00 00 00 00 00 82 00
16 00
> > -->  38 18 04 00 7e 00 40 00 00 00 08 00 00 00
00 00
> > -->  01 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00
> > -->  00 00 00 00 00 00 00 00 b1 18 40 00 54 00
40 00
> > -->  01 00 01 00 80 00 01 00 01 00 01 00 01 00
14 00
> > -->  3b 03 05 00 7e 00 40 00 00 00 00 00 00 00
00 00
> > -->  82 00 16 00 3e 00 07 00 b1 18 40 00 73 00
40 00
> > -->  7e 00 40 00 00 00 00 00 00 00 00 00 82 00
16 00
> > [....]
> >
> > And it just goes on like that.  The NULLs are what
leads me to believe
> > that I'm getting back data that the kernel copied
from the wrong part
> > of memory (that and the output is different every
time I run it, even
> > though it's the same GET message).
>
>
> Possibly related to ip_queue TSO handling bugs in old
kernels. Are
> you using TSO?
>

I had also forgot to mention that when running tethereal,
the packet
contents looked fine.  Not sure what the differences are
between how
tethereal captures packets and how ip_queue reads packets.




Nick

On 7/6/07, Nick Landry <nick.landrygmail.com> wrote:
> Checked TSO, and it turns out it is disabled at
startup.  I'm really
> stumped on this one.
>
>
>
> Nick
>
> On 7/6/07, Patrick McHardy <kabertrash.net> wrote:
> > Nick Landry wrote:
> > > Thanks, I checked that but the issue is that
I am sending the exact
> > > same GET request (Accept-Encoding is the same
as well) for when the
> > > message passes through any of the machines. 
The read from ip_queue
> > > for one machine is headers + ascii which is
what I'd expect.  The
> > > other machine outputs headers + junk.
> > >
> > > Here's a hex dump for the machine that isn't
working (payload length
> > > is 1500 bytes but I'll only print a small
part):
> > >
> > > -->  45 00 05 78 02 37 40 00 42 06 18 5b
0a b3 00 0c
> > > -->  0a 2b 04 05 c5 3a 00 50 26 a2 08 34
a8 d5 7c f7
> > > -->  80 10 4f b0 de f3 00 00 08 0a e4 eb
14 02 d5 6e
> > > -->  e4 1c 00 00 08 00 01 00 06 00 0f f7
b5 9b 00 00
> > > -->  00 00 00 00 00 00 00 00 30 00 00 00
00 00 00 00
> > > -->  45 00 00 30 bf 76 40 00 7c 06 d4 35
0a b1 2c 0f
> > > -->  0a b3 29 a9 13 4b 01 bd 29 7a 9e 75
00 00 00 00
> > > -->  70 02 40 00 fb 0b 00 00 02 04 05 b4
01 01 04 02
> > > -->  01 01 04 02 00 15 17 29 49 62 08 00
45 08 00 34
> > > -->  64 1b 40 00 40 06 be 0d 0a 2a 02 21
0a 2a 02 1f
> > > -->  80 03 bb 06 8c bc 41 58 79 bb 93 af
80 10 80 00
> > > -->  62 96 00 00 01 01 08 0a 00 2d 7d cc
19 d0 cd 3f
> > > -->  b1 18 40 00 7e 00 40 00 00 00 00 00
82 00 16 00
> > > -->  38 18 04 00 7e 00 40 00 00 00 08 00
00 00 00 00
> > > -->  01 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00
> > > -->  00 00 00 00 00 00 00 00 b1 18 40 00
54 00 40 00
> > > -->  01 00 01 00 80 00 01 00 01 00 01 00
01 00 14 00
> > > -->  3b 03 05 00 7e 00 40 00 00 00 00 00
00 00 00 00
> > > -->  82 00 16 00 3e 00 07 00 b1 18 40 00
73 00 40 00
> > > -->  7e 00 40 00 00 00 00 00 00 00 00 00
82 00 16 00
> > > [....]
> > >
> > > And it just goes on like that.  The NULLs are
what leads me to believe
> > > that I'm getting back data that the kernel
copied from the wrong part
> > > of memory (that and the output is different
every time I run it, even
> > > though it's the same GET message).
> >
> >
> > Possibly related to ip_queue TSO handling bugs in
old kernels. Are
> > you using TSO?
> >
>