USN-3695-2: Linux kernel (HWE) vulnerabilities

USN-3695-1 fixed vulnerabilities in the Linux kernel for Ubuntu 18.04 LTS. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 18.04 LTS for Ubuntu 16.04 LTS. Wen Xu discovered that the ext4 file system implementation in the Linux kernel did not properly initialize the crc32c checksum driver. A local attacker could use this to cause a denial of service (system crash). (CVE-2018-1094) It was discovered that the cdrom driver in the Linux kernel contained an incorrect bounds check. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2018-10940) Wen Xu discovered that the ext4 file system implementation in the Linux kernel did not properly validate xattr sizes. A local attacker could use this to cause a denial of service (system crash). (CVE-2018-1095) Jann Horn discovered that the 32 bit adjtimex() syscall implementation for 64 bit Linux kernels did not properly initialize memory returned to user space in some situations. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2018-11508) It was discovered that an information leak vulnerability existed in the floppy driver in the Linux kernel. A local attacker could use this to expose sensitive information (kernel memory). (CVE-2018-7755)