The kernel packages contain the Linux kernel, the core of any Linux operating system. This update fixes the following security issues: * multiple flaws were found in the mmap and mremap implementations. A local user could use these flaws to cause a local denial of service or escalate their privileges. * a NULL pointer dereference flaw was found in the Fast Userspace Mutexes implementation. The unlock code path did not check if the futex value associated with pi_state->owner had been modified. A local user could use this flaw to modify the futex value, possibly leading to a denial of service or privilege escalation when the pi_state->owner pointer is dereferenced. * a NULL pointer dereference flaw was found in the Linux kernel Network File System implementation. A local user on a system that has an NFS-mounted file system could use this flaw to cause a denial of service or escalate their privileges on that system. * a flaw was found in the sctp_process_unk_param function in the Linux kernel Stream Control Transmission Protocol implementation. A remote attacker could send a specially-crafted SCTP packet to an SCTP listening port on a target system, causing a kernel panic . * a flaw was found in the Linux kernel Transparent Inter-Process Communication protocol implementation. If a client application, on a local system where the tipc module is not yet in network mode, attempted to send a message to a remote TIPC node, it would dereference a NULL pointer on the local system, causing a kernel panic . * a buffer overflow flaw was found in the Linux kernel Global File System 2 implementation. In certain cases, a quota could be written past the end of a memory page, causing memory corruption, leaving the quota stored on disk in an invalid state. A user with write access to a GFS2 file system could trigger this flaw to cause a kernel crash or escalate their privileges on the GFS2 server. This issue can only be triggered if the GFS2 file system is mounted with the "quota=on" or "quota=account" mount option. * a race condition between finding a keyring by name and destroying a freed keyring was found in the Linux kernel key management facility. A local user could use this flaw to cause a kernel panic or escalate their privileges. * a flaw was found in the link_path_walk function in the Linux kernel. Using the file descriptor returned by the open function with the O_NOFOLLOW flag on a subordinate NFS-mounted file system, could result in a NULL pointer dereference, causing a denial of service or privilege escalation. * a missing permission check was found in the gfs2_set_flags function in the Linux kernel GFS2 implementation. A local user could use this flaw to change certain file attributes of files, on a GFS2 file system, that they do not own. Red Hat would like to thank Jukka Taimisto and Olli Jarva of Codenomicon Ltd, Nokia Siemens Networks, and Wind River on behalf of their customer, for responsibly reporting CVE-2010-1173; Mario Mikocevic for responsibly reporting CVE-2010-1436; and Dan Rosenberg for responsibly reporting CVE-2010-1641. This update also fixes several bugs. The system must be rebooted for this update to take effect.