7.8 - MDVSA-2015:058

Multiple vulnerabilities has been found and corrected in the Linux kernel:

The Crypto API in the Linux kernel before 3.18.5 allows local users to load arbitrary kernel modules via a bind system call for an AF_ALG socket with a module name in the salg_name field, a different vulnerability than CVE-2014-9644 (CVE-2013-7421).

arch/x86/kvm/vmx.c in the KVM subsystem in the Linux kernel before 3.17.2 on Intel processors does not ensure that the value in the CR4 control register remains the same after a VM entry, which allows host OS users to kill arbitrary processes or cause a denial of service (system disruption) by leveraging /dev/kvm access, as demonstrated by PR_SET_TSC prctl calls within a modified copy of QEMU (CVE-2014-3690).

arch/x86/kernel/tls.c in the Thread Local Storage (TLS) implementation in the Linux kernel through 3.18.1 allows local users to bypass the espfix protection mechanism, and consequently makes it easier for local users to bypass the ASLR protection mechanism, via a crafted application that makes a set_thread_area system call and later reads a 16-bit value (CVE-2014-8133).

net/netfilter/nf_conntrack_proto_generic.c in the Linux kernel before 3.18 generates incorrect conntrack entries during handling of certain iptables rule sets for the SCTP, DCCP, GRE, and UDP-Lite protocols, which allows remote attackers to bypass intended access restrictions via packets with disallowed port numbers (CVE-2014-8160).

The Linux kernel through 3.17.4 does not properly restrict dropping of supplemental group memberships in certain namespace scenarios, which allows local users to bypass intended file permissions by leveraging a POSIX ACL containing an entry for the group category that is more restrictive than the entry for the other category, aka a negative groups issue, related to kernel/groups.c, kernel/uid16.c, and kernel/user_namespace.c (CVE-2014-8989).

The __switch_to function in arch/x86/kernel/process_64.c in the Linux kernel through 3.18.1 does not ensure that Thread Local Storage (TLS) descriptors are loaded before proceeding with other steps, which makes it easier for local users to bypass the ASLR protection mechanism via a crafted application that reads a TLS base address (CVE-2014-9419).

The rock_continue function in fs/isofs/rock.c in the Linux kernel through 3.18.1 does not restrict the number of Rock Ridge continuation entries, which allows local users to cause a denial of service (infinite loop, and system crash or hang) via a crafted iso9660 image (CVE-2014-9420).

The batadv_frag_merge_packets function in net/batman-adv/fragmentation.c in the B.A.T.M.A.N. implementation in the Linux kernel through 3.18.1 uses an incorrect length field during a calculation of an amount of memory, which allows remote attackers to cause a denial of service (mesh-node system crash) via fragmented packets (CVE-2014-9428).

Race condition in the key_gc_unused_keys function in security/keys/gc.c in the Linux kernel through 3.18.2 allows local users to cause a denial of service (memory corruption or panic) or possibly have unspecified other impact via keyctl commands that trigger access to a key structure member during garbage collection of a key (CVE-2014-9529).

The parse_rock_ridge_inode_internal function in fs/isofs/rock.c in the Linux kernel before 3.18.2 does not validate a length value in the Extensions Reference (ER) System Use Field, which allows local users to obtain sensitive information from kernel memory via a crafted iso9660 image (CVE-2014-9584).

The vdso_addr function in arch/x86/vdso/vma.c in the Linux kernel through 3.18.2 does not properly choose memory locations for the vDSO area, which makes it easier for local users to bypass the ASLR protection mechanism by guessing a location at the end of a PMD (CVE-2014-9585).

The Crypto API in the Linux kernel before 3.18.5 allows local users to load arbitrary kernel modules via a bind system call for an AF_ALG socket with a parenthesized module template expression in the salg_name field, as demonstrated by the vfat(aes) expression, a different vulnerability than CVE-2013-7421 (CVE-2014-9644).

Off-by-one error in the ecryptfs_decode_from_filename function in fs/ecryptfs/crypto.c in the eCryptfs subsystem in the Linux kernel before 3.18.2 allows local users to cause a denial of service (buffer overflow and system crash) or possibly gain privileges via a crafted filename (CVE-2014-9683).

The em_sysenter function in arch/x86/kvm/emulate.c in the Linux kernel before 3.18.5, when the guest OS lacks SYSENTER MSR initialization, allows guest OS users to gain guest OS privileges or cause a denial of service (guest OS crash) by triggering use of a 16-bit code segment for emulation of a SYSENTER instruction (CVE-2015-0239).

The updated packages provides a solution for these security issues.