| Description: | The kernel packages contain the Linux kernel, the core of any Linuxoperating system.It was found that the Linux kernel's ping socket implementation did notproperly handle socket unhashing during spurious disconnects, which couldlead to a use-after-free flaw. On x86-64 architecture systems, a local userable to create ping sockets could use this flaw to crash the system.On non-x86-64 architecture systems, a local user able to create pingsockets could use this flaw to escalate their privileges on the system.(CVE-2015-3636, Moderate)This update also fixes the following bugs:Due to bad memory or memory corruption, an isolated BUG_ON(mm->nr_ptes)was sometimes reported, indicating that not all the page tables allocatedcould be found and freed when the exit_mmap() function cleared the useraddress space. As a consequence, a kernel panic occurred. To fix this bug,the BUG_ON() function has been replaced by WARN_ON(), which prevents thekernel from panicking in the aforementioned situation. (BZ#1235929)Previously, it was for the ext4 driver to read a metadata block and useit without a verification. If the metadata block was corrupted, a kernelpanic could occur. With this update, verification is forced on every bufferbefore it is used, which uncovers possible corruption and prevents furtheruse of the corrupted metadata buffer. (BZ#1242930)All kernel users are advised to upgrade to these updated packages, whichcontain backported patches to correct these issues. The system must berebooted for this update to take effect. |