USN-110-1: Linux kernel vulnerabilities

Releases

• Ubuntu 4.10

Details

Alexander Nyberg discovered an integer overflow in the
sysfs_write_file() function. A local attacker could exploit this to
crash the kernel or possibly even execute arbitrary code with root
privileges by writing to an user-writable file in /sys under certain
low-memory conditions. However, there are very few cases where a
user-writeable sysfs file actually exists. (CAN-2005-0867)

Olof Johansson discovered a Denial of Service vulnerability in the
futex functions, which provide semaphores for exclusive locking of
resources. A local attacker could possibly exploit this to cause a
kernel deadlock. (CAN-2005-0937)

In addition this update fixes two race conditions in the ext3 and jfs
file system drivers, which could lead to a kernel crash under certain
(unusual) conditions. However, these cannot easily be triggered by
users, thus they are not security sensitive.
(http://linux.bkbits.net:8080/linux-2.5/gnupatch@4248d87aETPJX79hVXl4owAUwu2SmQ,
http://linux.bkbits.net:8080/linux-2.6/cset@1.2181.46.242)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 4.10

• linux-image-2.6.8.1-5-amd64-k8-smp -
• linux-image-2.6.8.1-5-686 -
• linux-image-2.6.8.1-5-amd64-generic -
• linux-image-2.6.8.1-5-powerpc-smp -
• linux-image-2.6.8.1-5-k7-smp -
• linux-patch-debian-2.6.8.1 -
• linux-image-2.6.8.1-5-power4-smp -
• linux-image-2.6.8.1-5-power3-smp -
• linux-image-2.6.8.1-5-amd64-xeon -
• linux-image-2.6.8.1-5-k7 -
• linux-image-2.6.8.1-5-power3 -
• linux-image-2.6.8.1-5-power4 -
• linux-image-2.6.8.1-5-686-smp -
• linux-image-2.6.8.1-5-powerpc -
• linux-image-2.6.8.1-5-amd64-k8 -
• linux-source-2.6.8.1 -
• linux-image-2.6.8.1-5-386 -

In general, a standard system update will make all the necessary changes.

References

• CVE-2005-0937
• CVE-2005-0867