The pn_recvmsg function in net/phonet/datagram.c in the Linux kernel before 3.12.4 updates a certain length value before ensuring that an associated data structure has been initialized, which allows local users to obtain sensitive information from kernel stack memory via a recvfrom, recvmmsg, or recvmsg system call. The security_context_to_sid_core function in security/selinux/ss/services.c in the Linux kernel before 3.13.4 allows local users to cause a denial of service by leveraging the CAP_MAC_ADMIN capability to set a zero-length security context. The Linux kernel before 3.12.4 updates certain length values before ensuring that associated data structures have been initialized, which allows local users to obtain sensitive information from kernel stack memory via a recvfrom, recvmmsg, or recvmsg system call, related to net/ipv4/ping.c, net/ipv4/raw.c, net/ipv4/udp.c, net/ipv6/raw.c, and net/ipv6/udp.c. The cifs_iovec_write function in fs/cifs/file.c in the Linux kernel through 3.13.5 does not properly handle uncached write operations that copy fewer than the requested number of bytes, which allows local users to obtain sensitive information from kernel memory, cause a denial of service , or possibly gain privileges via a writev system call with a crafted pointer.