On Wed, Sep 21, 2011 at 10:26 PM, Abu Rasheda <rcpilot2010@gmail.com> wrote:
I am inserting packets into Linux stack and they are accepted by net_rx function, but are latter dropped. What tools are available in Linux kernel to for debugging this issue.

I discovered that /proc/net/snmp files provides stats about packet processing. This show stats for IP, ICMP, UDP and TCP. It is possible to map stats from this file to actual kernel code and pinpoint where error is happening.