Off-by-one error in the pipe_advance function in lib/iov_iter.c in the Linux kernel before 4.9.5 allows local users to obtain sensitive information from uninitialized heap-memory locations in opportunistic circumstances by reading from a pipe after an incorrect buffer-release decision. It was discovered that a fencepost error existed in the pipe_advance() function in the Linux kernel. A local attacker could use this to expose sensitive information (kernel memory).