Updated kernel packages fix security vulnerabilities

This kernel update is based on upstream 4.1.15 longterm kernel and fixes the following security issues: The __rds_conn_create function in net/rds/connection.c in the Linux kernel through 4.2.3 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by using a socket that was not properly bound (CVE-2015-6937). The key_gc_unused_keys function in security/keys/gc.c in the Linux kernel through 4.2.6 allows local users to cause a denial of service (OOPS) via crafted keyctl commands (CVE-2015-7872). The vivid_fb_ioctl function in drivers/media/platform/vivid/vivid-osd.c in the Linux kernel through 4.3.3 does not initialize a certain structure member, which allows local users to obtain sensitive information from kernel memory via a crafted application (CVE-2015-7884). The dgnc_mgmt_ioctl function in drivers/staging/dgnc/dgnc_mgmt.c in the Linux kernel through 4.3.3 does not initialize a certain structure member, which allows local users to obtain sensitive information from kernel memory via a crafted application (CVE-2015-7885). Felix Wilhelm discovered a race condition in the Xen paravirtualized drivers which can cause double fetch vulnerabilities. An attacker in the paravirtualized guest could exploit this flaw to cause a denial of service (crash the host) or potentially execute arbitrary code on the host (CVE-2015-8550 / XSA-155). Konrad Rzeszutek Wilk discovered the Xen PCI backend driver does not perform sanity checks on the device’s state. An attacker could exploit this flaw to cause a denial of service (NULL dereference) on the host (CVE-2015-8551 / XSA-157). Konrad Rzeszutek Wilk discovered the Xen PCI backend driver does not perform sanity checks on the device’s state. An attacker could exploit this flaw to cause a denial of service by flooding the logging system with WARN() messages causing the initial domain to exhaust disk space (CVE-2015-8552 / XSA-157). The ovl_setattr function in fs/overlayfs/inode.c in the Linux kernel through 4.3.3 attempts to merge distinct setattr operations, which allows local users to bypass intended access restrictions and modify the attributes of arbitrary overlay files via a crafted application (CVE-2015-8660). For other fixes in this update, see the referenced changelogs.