Updated kernel-rt packages that fix several security issues and various bugs are now available for Red Hat Enterprise MRG 1.1.3. This update has been rated as having important security impact by the Red Hat Security Response Team.
The kernel-rt packages contain the Linux kernel, the core of any Linux operating system. These updated packages fix the following security issues: * a buffer overflow flaw was found in the CIFSTCon() function of the Linux kernel Common Internet File System (CIFS) implementation. When mounting a CIFS share, a malicious server could send an overly-long string to the client, possibly leading to a denial of service or privilege escalation on the client mounting the CIFS share. (CVE-2009-1439, Important) * the Linux kernel Network File System daemon (nfsd) implementation did not drop the CAP_MKNOD capability when handling requests from local, unprivileged users. This flaw could possibly lead to an information leak or privilege escalation. (CVE-2009-1072, Moderate) * a deficiency was found in the Linux kernel signals implementation. The kill_something_info() function did not check if a process was outside the caller's namespace before sending the kill signal, making it possible to kill processes in all process ID (PID) namespaces, breaking PID namespace isolation. (CVE-2009-1338, Moderate) * a flaw was found in the AGPGART driver. The agp_generic_alloc_page() and agp_generic_alloc_pages() functions did not zero out the memory pages they allocate, which may later be available to user-space processes. This flaw could possibly lead to an information leak. (CVE-2009-1192, Low) These updated packages also fix the following bugs: * the "-fwrapv" flag was added to the gcc build options to prevent gcc from optimizing away wrapping arithmetic, as optimizing away wrapping may lead to unexpected results. (BZ#491264) * the bnx2x driver may have failed when highly-stressed by network stress-tests, resulting in network access being unavailable. This driver has been updated to resolve this issue. (BZ#495472) * the file system mask, which lists capabilities for users with a file system user ID (fsuid) of 0, was missing the CAP_MKNOD and CAP_LINUX_IMMUTABLE capabilities. This could, potentially, allow users with an fsuid other than 0 to perform actions on some file system types that would otherwise be prevented. This update adds these capabilities. (BZ#497047) * "/proc/[pid]/maps" and "/proc/[pid]/smaps" can only be read by processes able to use the ptrace() call on a given process; however, certain information from "/proc/[pid]/stat" and "/proc/[pid]/wchan" could be used to reconstruct memory maps, making it possible to bypass the Address Space Layout Randomization (ASLR) security feature. This update addresses this issue. (BZ#499550) * the get_random_int() function returned the same number until the jiffies counter (which ticks at a clock interrupt frequency) or process ID (PID) changed, making it possible to predict the random numbers. This may have helped to bypass the ASLR security feature. With this update, get_random_int() is more random and no longer uses a common seed value. This reduces the possibility of predicting the values get_random_int() returns. (BZ#499787) All Red Hat Enterprise MRG users should upgrade to these updated packages, which contain backported patches to resolve these issues. Note: The system must be rebooted for this update to take effect.