Red Hat Enterprise Linux 5 RHSA-2008:0957-02 Important Kernel Update

The kernel packages contain the Linux kernel, the core of any Linux operating system.
* the Xen implementation did not prevent applications running in a para-virtualized guest from modifying CR4 TSC. This could cause a local denial of service. (CVE-2007-5907, Important)
* Tavis Ormandy reported missing boundary checks in the Virtual Dynamic Shared Objects (vDSO) implementation. This could allow a local unprivileged user to cause a denial of service or escalate privileges. (CVE-2008-3527, Important)
* the do_truncate() and generic_file_splice_write() functions did not clear the setuid and setgid bits. This could allow a local unprivileged user to obtain access to privileged information. (CVE-2008-4210, CVE-2008-3833, Important)
* a flaw was found in the Linux kernel splice implementation. This could cause a local denial of service when there is a certain failure in the add_to_page_cache_lru() function. (CVE-2008-4302, Important)
* a flaw was found in the Linux kernel when running on AMD64 systems. During a context switch, EFLAGS were being neither saved nor restored. This could allow a local unprivileged user to cause a denial of service. (CVE-2006-5755, Low)
* a flaw was found in the Linux kernel virtual memory implementation. This could allow a local unprivileged user to cause a denial of service. (CVE-2008-2372, Low)
* an integer overflow was discovered in the Linux kernel Datagram Congestion Control Protocol (DCCP) implementation. This could allow a remote attacker to cause a denial of service. By default, remote DCCP is blocked by SELinux. (CVE-2008-3276, Low)
In addition, these updated packages fix the following bugs:
* random32() seeding has been improved.
* in a multi-core environment, a race between the QP async event-handler and the destro_qp() function could occur. This led to unpredictable results during invalid memory access, which could lead to a kernel crash.
* a format string was omitted in the call to the request_module() function.
* a stack overflow caused by an infinite recursion bug in the binfmt_misc kernel module was corrected.
* the ata_scsi_rbuf_get() and ata_scsi_rbuf_put() functions now check for scatterlist usage before calling kmap_atomic().
* a sentinel NUL byte was added to the device_write() function to ensure that lspace.name is NUL-terminated.
* in the character device driver, a range_is_allowed() check was added to the read_mem() and write_mem() functions. It was possible for an illegitimate application to bypass these checks, and access /dev/mem beyond the 1M limit by calling mmap_mem() instead. Also, the parameters of range_is_allowed() were changed to cleanly handle greater than 32-bits of physical address on 32-bit architectures.
* some of the newer Nehalem-based systems declare their CPU DSDT entries as type "Alias". During boot, this caused an "Error attaching device data" message to be logged.
* the evtchn event channel device lacked locks and memory barriers. This has led to xenstore becoming unresponsive on the Itanium® architecture.
* sending of gratuitous ARP packets in the Xen frontend network driver is now delayed until the backend signals that its carrier status has been processed by the stack.
* on forcedeth devices, whenever setting ethtool parameters for link speed, the device could stop receiving interrupts.
* the CIFS 'forcedirectio' option did not allow text to be appended to files.
* the gettimeofday() function returned a backwards time on Intel® 64.
* residual-count corrections during UNDERRUN handling were added to the qla2xxx driver.
* the fix for a small quirk was removed for certain Adaptec controllers for which it caused problems.
* the "xm trigger init" command caused a domain panic if a userland application was running on a guest on the Intel® 64 architecture.
Users of kernel should upgrade to these updated packages, which contain backported patches to correct these issues.