An information leak was found in the Linux kernel. The __get_user_asm_ex macro in arch/x86/include/asm/uaccess.h in the Linux kernel before 4.7.5 does not initialize a certain integer variable, which allows local users to obtain sensitive information from kernel stack memory by triggering failure of a get_user_ex call.
Created kernel tracking bugs for this issue:
Affects: fedora-all [bug 1391910]
This issue was fixed in 4.7.5 stable updates across all Fedora releases.
This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 as the code which can trigger the flaw is not present in the products listed.
This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 6, 7 and MRG-2. This has been rated as having Low security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.