Bug 1476664 - ss filter parsing bug causes crash
Summary: ss filter parsing bug causes crash
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: iproute
Version: 6.9
Hardware: All
OS: Linux
Target Milestone: rc
: ---
Assignee: Phil Sutter
QA Contact: Jaroslav Aster
Ioanna Gkioka
Depends On:
Blocks: 1506394
TreeView+ depends on / blocked
Reported: 2017-07-31 06:43 UTC by Martin Schwenke
Modified: 2018-06-19 05:11 UTC (History)
10 users (show)

Fixed In Version: iproute-2.6.32-57.el6
Doc Type: Bug Fix
Doc Text:
The `ss` program no longer stops when providing a long list of filters Previously, providing a long list of filters to the "ss" command caused an integer value overflow. As a consequence, the 'ss' tool could stop the program execution. With this update, faulty bits in the source code are corrected, and the described problem no longer occurs.
Clone Of:
Last Closed: 2018-06-19 05:10:41 UTC
Target Upstream Version:

Attachments (Terms of Use)

System ID Priority Status Summary Last Updated
Debian BTS 511720 None None None 2017-07-31 06:43:26 UTC
Red Hat Product Errata RHBA-2018:1867 None None None 2018-06-19 05:11:00 UTC

Description Martin Schwenke 2017-07-31 06:43:27 UTC
Description of problem:

ss crashes when the filter is too long/complex

Version-Release number of selected component (if applicable):


How reproducible:

Very reliable

Steps to Reproduce:

1. valgrind -q ss -tn state established 'src || src || src || src || src || src || src || src'  

Actual results:

  Recv-Q Send-Q    Local Address:Port      Peer Address:Port 
  ==4372== Warning: silly arg (-100) to malloc()
  Aborted (core dumped)

Expected results:

  A possibly empty list of connections.  valgrind still complains but it is at least non-fatal.

Additional info:

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:

commit 2a4fa1c305742e4bfbc2960c40e0d1ee55b30694
Author: Andreas Henriksson <andreas@fatal.se>
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 <andreas@debian.org>
    Signed-off-by: Andreas Henriksson <andreas@fatal.se>
    Reviewed-by: Eric Dumazet <edumazet@google.com>

Comment 15 errata-xmlrpc 2018-06-19 05:10:41 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.


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