Bug 651892 (CVE-2010-4160)

Summary: CVE-2010-4160 kernel: L2TP send buffer allocation size overflows
Product: [Other] Security Response Reporter: Petr Matousek <pmatouse>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: arozansk, bhu, davej, fhrbata, jkacur, kmcmartin, lgoncalv, lwang, tcallawa, vdanen, williams
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2012-03-28 08:45:26 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 651893, 651894, 651895    
Bug Blocks:    

Description Petr Matousek 2010-11-10 15:14:41 UTC 
Description of problem:
Both PPPoL2TP (in net/l2tp/l2tp_ppp.c, pppol2tp_sendmsg()) and IPoL2TP (in net/l2tp/l2tp_ip.c, l2tp_ip_sendmsg()) make calls to sock_wmalloc() that perform arithmetic on the size argument without any maximum bound. As a result, by issuing sendto() calls with very large sizes, this allocation size will wrap and result in a small buffer being allocated, leading to ugliness immediately after (probably kernel panics due to bad sk_buff tail position, but possibly kernel heap corruption).

Reference:
http://www.spinics.net/lists/netdev/msg145673.html

Acknowledgements:

Red Hat would like to thank Dan Rosenberg for reporting this issue.
Comment 2 Petr Matousek 2010-11-10 15:19:53 UTC 
Statement:

The Linux kernel as shipped with Red Hat Enterprise Linux 3, 4 and 5 did not
include L2TP functionality, and therefore are not affected by this
issue. This has been addressed in Red Hat Enterprise Linux 6 and Red Hat
Enterprise MRG via https://rhn.redhat.com/errata/RHSA-2011-0007.html and https://rhn.redhat.com/errata/RHSA-2011-0330.html.
Comment 4 Vincent Danen 2010-11-10 21:53:42 UTC 
This issue has been assigned the name CVE-2010-4160.
Comment 6 Eugene Teo (Security Response) 2010-11-25 05:47:38 UTC 
http://git.kernel.org/linus/253eacc070b114c2ec1f81b067d2fed7305467b0
http://git.kernel.org/linus/8acfe468b0384e834a303f08ebc4953d72fb690a
Comment 8 errata-xmlrpc 2011-01-11 19:45:22 UTC 
This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2011:0007 https://rhn.redhat.com/errata/RHSA-2011-0007.html
Comment 9 errata-xmlrpc 2011-03-10 20:04:23 UTC 
This issue has been addressed in following products:

  MRG for RHEL-5

Via RHSA-2011:0330 https://rhn.redhat.com/errata/RHSA-2011-0330.html