Bug#503020: linux-image: tcp_dsack causes hangs when using proxy server

[Jonathan Zdziarski <jonathan@zdziarski.com>]

Package: linux-image
Severity: normal

net.ipv4.tcp_dsack is enabled by default, and for some reason causes certain
websites to hang when downloading web pages through a proxy. For example:

curl -x [my proxy] http://www.zdziarski.com

causes the web page to hang every other query. disabling net.ipv4.tcp_dsack
seems to resolve the problem, leaving me to believe something might be wrong
in how linux handles dupe sacks.

-- System Information:
Debian Release: 4.0
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18-6-686
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)