Bug 283821 (CVE-2009-2695)

Summary:	Kernel: mmap-to-zero-page bypass (CVE-2009-2695)
Product:	Gentoo Security	Reporter:	Alex Legler (RETIRED) <a3li>
Component:	Kernel	Assignee:	Gentoo Security <security>
Status:	RESOLVED FIXED
Severity:	normal	CC:	hardened-kernel+disabled, kernel
Priority:	High
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=788084aba2ab7348257597496befcbccabdc98a3
Whiteboard:	[linux <2.6.31]
Package list:		Runtime testing required:	---

Description Alex Legler (RETIRED) archtester

2009-09-06 09:46:58 UTC

CVE-2009-2695 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2009-2695):
  The Linux kernel before 2.6.31-rc7 does not properly prevent mmap
  operations that target page zero and other low memory addresses,
  which allows local users to gain privileges by exploiting NULL
  pointer dereference vulnerabilities, related to (1) the default
  configuration of the allow_unconfined_mmap_low boolean in SELinux on
  Red Hat Enterprise Linux (RHEL) 5, (2) an error that causes
  allow_unconfined_mmap_low to be ignored in the unconfined_t domain,
  (3) lack of a requirement for the CAP_SYS_RAWIO capability for these
  mmap operations, and (4) interaction between the mmap_min_addr
  protection mechanism and certain application programs.

Comment 1 Bjoern Tropf (RETIRED) gentoo-dev

2009-09-06 12:32:03 UTC

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=ab5a91a8364c3d6fc617abc47cc81d162c01d90a
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=9c0d90103c7e0eb6e638e5b649e9f6d8d9c1b4b3
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=8cf948e744e0218af604c32edecde10006dc8e9e
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=788084aba2ab7348257597496befcbccabdc98a3
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1d9959734a1949ea4f2427bd2d8b21ede6b2441c