CVE ID:	CVE-2015-7550
Description:	The keyctl_read_key function in security/keys/keyctl.c in the Linux kernel before 4.3.4 does not properly use a semaphore, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a crafted application that leverages a race condition between keyctl_revoke and keyctl_read calls.
Test IDs:	1.3.6.1.4.1.25623.1.0.703434   1.3.6.1.4.1.25623.1.0.842653   1.3.6.1.4.1.25623.1.0.842654   1.3.6.1.4.1.25623.1.1.1.2.2016.378
Cross References:	Common Vulnerability Exposure (CVE) ID: CVE-2015-7550 79903 http://www.securityfocus.com/bid/79903 DSA-3434 http://www.debian.org/security/2016/dsa-3434 SUSE-SU-2016:0911 http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00094.html SUSE-SU-2016:1102 http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00045.html SUSE-SU-2016:2074 http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00038.html USN-2888-1 http://www.ubuntu.com/usn/USN-2888-1 USN-2890-1 http://www.ubuntu.com/usn/USN-2890-1 USN-2890-2 http://www.ubuntu.com/usn/USN-2890-2 USN-2890-3 http://www.ubuntu.com/usn/USN-2890-3 USN-2911-1 http://www.ubuntu.com/usn/USN-2911-1 USN-2911-2 http://www.ubuntu.com/usn/USN-2911-2 http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4a1b4f5047e4f54e194681125c74c0aa64d637d http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4a1b4f5047e4f54e194681125c74c0aa64d637d http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.3.4 http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.3.4 https://bugzilla.redhat.com/show_bug.cgi?id=1291197 https://bugzilla.redhat.com/show_bug.cgi?id=1291197 https://github.com/torvalds/linux/commit/b4a1b4f5047e4f54e194681125c74c0aa64d637d https://github.com/torvalds/linux/commit/b4a1b4f5047e4f54e194681125c74c0aa64d637d https://security-tracker.debian.org/tracker/CVE-2015-7550 https://security-tracker.debian.org/tracker/CVE-2015-7550