Red Hat Bugzilla – Bug 1476664
ss filter parsing bug causes crash
Last modified: 2017-11-22 07:25:16 EST
Description of problem:
ss crashes when the filter is too long/complex
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. valgrind -q ss -tn state established 'src 10.0.0.31:22 || src 10.0.0.32:22 || src 10.0.0.33:22 || src 10.0.0.34:22 || src 10.0.0.35:22 || src 10.0.0.36:22 || src 10.0.0.37:22 || src 10.0.0.38:22'
Recv-Q Send-Q Local Address:Port Peer Address:Port
==4372== Warning: silly arg (-100) to malloc()
Aborted (core dumped)
A possibly empty list of connections. valgrind still complains but it is at least non-fatal.
This can obviously be recreated without valgrind. However, valgrind points out the nature of the problem.
The problem is that the following upstream commit is missing:
Author: Andreas Henriksson <email@example.com>
Date: Wed Nov 13 09:46:42 2013 +0100
ss: avoid passing negative numbers to malloc
$ ss state established \( sport = :4060 or sport = :4061 or sport = :4062 or sport = :4063 or sport = :4064 or sport = :4065 or sport = :4066 or sport = :4067 \) > /dev/null
In the example above ssfilter_bytecompile(...) will return (int)136.
char l1 = 136; means -120 which will result in a negative number
being passed to malloc at misc/ss.c:913.
Simply declare l1 and l2 as integers to avoid the char overflow.
This is one of the issues originally reported in http://bugs.debian.org/511720
Fix the same problem in other code paths as well (thanks to Eric Dumazet).
Reported-by: Andreas Schuldei <firstname.lastname@example.org>
Signed-off-by: Andreas Henriksson <email@example.com>
Reviewed-by: Eric Dumazet <firstname.lastname@example.org>