The replace_map_fd_with_map_ptr function in kernel/bpf/verifier.c in the Linux kernel before 4.5.5 does not properly maintain an fd data structure, which allows local users to gain privileges or cause a denial of service (use-after-free) via crafted BPF instructions that reference an incorrect file descriptor.<a href=http://cwe.mitre.org/data/definitions/416.html>CWE-416: Use After Free</a> http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-4557
