CVE-2014-4171 Information

Description

mm/shmem.c in the Linux kernel through 3.15.1 does not properly implement the interaction between range notification and hole punching which allows local users to cause a denial of service (i_mutex hold) by using the mmap system call to access a hole as demonstrated by interfering with intended shmem activity by blocking completion of (1) an MADV_REMOVE madvise call or (2) an FALLOC_FL_PUNCH_HOLE fallocate call.

Reference

http://lists.opensuse.org/opensuse-security-announce/2014-10/msg00006.html http://lists.opensuse.org/opensuse-security-announce/2014-10/msg00007.html http://marc.info/?l=linux-mm-commits&m=140303745420549&w=2 http://ozlabs.org/~akpm/mmots/broken-out/shmem-fix-faulting-into-a-hole-while-its-punched.patch http://rhn.redhat.com/errata/RHSA-2014-1318.html http://rhn.redhat.com/errata/RHSA-2015-0102.html http://secunia.com/advisories/59777 http://secunia.com/advisories/60564 http://www.openwall.com/lists/oss-security/2014/06/18/11 http://www.securityfocus.com/bid/68157 http://www.securitytracker.com/id/1030450 http://www.ubuntu.com/usn/USN-2334-1 http://www.ubuntu.com/usn/USN-2335-1 https://bugzilla.redhat.com/show_bug.cgi?id=1111180