#946528 liblwip0: Bad TCP_MSS value

Package:
liblwip0
Source:
lwip
Description:
small implementation of the TCP/IP protocol suite - shared library
Submitter:
Ondřej Tůma
Date:
2022-07-06 08:39:03 UTC
Severity:
important
Tags:
#946528#5
Date:
2019-12-10 15:29:06 UTC
From:
To:
Dear Maintainer,

Creating TCP server with existing value in library crashed by bad memory using.
Valgrind found the problem in low_level_input function, which uses pbuf_alloc,
that allocate too less memory. This "original" value will work.
#946528#10
Date:
2019-12-22 08:45:05 UTC
From:
To:
Hi,

El 10/12/19 a les 16:29, Ondřej Tůma ha escrit:

low_level_info is usually implemented by the driver. Which driver are
you using? Are you using IPv6?
#946528#15
Date:
2019-12-22 08:45:05 UTC
From:
To:
Hi,

El 10/12/19 a les 16:29, Ondřej Tůma ha escrit:

low_level_info is usually implemented by the driver. Which driver are
you using? Are you using IPv6?
#946528#20
Date:
2020-01-20 20:37:32 UTC
From:
To:
Hi,

El 14/1/20 a les 8:50, Ondřej Tůma ha escrit:

I'm reluctant to change the TCP tuning values without a good reason,
because any value will always fit for some cases and be inappropriate
for others. Besides, I don't see how it's the MSS value related to this
bug. And anyway, memory bugs in C are always tricky, the problem can be
produced in any other place than the place where they manifest.

Reading your code I assume you're using the tapif driver that is
distributed with lwip, could the problem be the harcoded size of the
input buffer? [1]

------------
[1]
http://git.savannah.nongnu.org/cgit/lwip.git/tree/contrib/ports/unix/port/netif/tapif.c#n267
#946528#27
Date:
2020-03-08 16:57:42 UTC
From:
To:
I'll wait a few months for an answer before closing the bug
#946528#32
Date:
2022-07-06 08:27:53 UTC
From:
To:
Closing this

El 8/3/20 a les 17:57, Joan Lledó ha escrit: