Bug 406171 (CVE-2012-1090)

Summary:	kernel: linux 2.6.31 cifs dentry refcount leak when opening a FIFO on lookup leads to panic on unmount (CVE-2012-1090)
Product:	Gentoo Security	Reporter:	Michael Harrison <n0idx80>
Component:	Kernel	Assignee:	Gentoo Kernel Security <security-kernel>
Status:	RESOLVED OBSOLETE
Severity:	minor	CC:	kernel
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	https://bugzilla.redhat.com/show_bug.cgi?id=798293
Whiteboard:	[linux 2.6.31]
Package list:		Runtime testing required:	---

Description Michael Harrison 2012-02-28 16:22:34 UTC

The cifs code will attempt to open files on lookup under certain circumstances.
What happens though if we find that the file we opened was actually a FIFO or
other special file? Currently, the open filehandle just ends up being leaked
leading to a dentry refcount mismatch and oops on umount.

An unprivileged local user could use this flaw to crash the system.

Introduced by:
a6ce4932fbdbcd8f8e8c6df76812014351c32892

Proposed upstream patch:
http://thread.gmane.org/gmane.linux.kernel.cifs/5526

Comment 1 Aaron Bauman (RETIRED) gentoo-dev

2018-04-04 18:09:51 UTC

There are no longer any 2.x or <3.2.10 kernels available in the repository with the exception of sys-kernel/xbox-sources which is unsupported by security.