The kernel packages contain the Linux kernel, the core of any Linux operating system.
This update fixes the following security issues:
A missing boundary check was found in the dvb_ca_ioctl() function in the Linux kernel's av7110 module. On systems that use old DVB cards that require the av7110 module, a local, unprivileged user could use this flaw to cause a denial of service or escalate their privileges. (CVE-2011-0521, Important)
An inconsistency was found in the interaction between the Linux kernel's method for allocating NFSv4 (Network File System version 4) ACL data and the method by which it was freed. This inconsistency led to a kernel panic which could be triggered by a local, unprivileged user with files owned by said user on an NFSv4 share. (CVE-2011-1090, Moderate)
A NULL pointer dereference flaw was found in the Generic Receive Offload (GRO) functionality in the Linux kernel's networking implementation. If both GRO and promiscuous mode were enabled on an interface in a virtual LAN (VLAN), it could result in a denial of service when a malformed VLAN frame is received on that interface. (CVE-2011-1478, Moderate)
A missing security check in the Linux kernel's implementation of the install_special_mapping() function could allow a local, unprivileged user to bypass the mmap_min_addr protection mechanism. (CVE-2010-4346, Low)
An information leak was found in the Linux kernel's task_show_regs() implementation. On IBM S/390 systems, a local, unprivileged user could use this flaw to read /proc/[PID]/status files, allowing them to discover the CPU register values of processes. (CVE-2011-0710, Low)
A missing validation check was found in the Linux kernel's mac_partition() implementation, used for supporting file systems created on Mac OS operating systems. A local attacker could use this flaw to cause a denial of service by mounting a disk that contains specially-crafted partitions. (CVE-2011-1010, Low)
Red Hat would like to thank Ryan Sweat for reporting CVE-2011-1478; Tavis Ormandy for reporting CVE-2010-4346; and Timo Warns for reporting CVE-2011-1010.
This update also fixes several bugs. Documentation for these bug fixes will be available shortly from the Technical Notes document linked to in the References section.
Users should upgrade to these updated packages, which contain backported patches to correct these issues, and fix the bugs noted in the Technical Notes. The system must be rebooted for this update to take effect.