CVE-2016-6516

Description

Race condition in the ioctl_file_dedupe_range function in fs/ioctl.c in the Linux kernel through 4.7 allows local users to cause a denial of service (heap-based buffer overflow) or possibly gain privileges by changing a certain count value, aka a "double fetch" vulnerability.

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

Debian

Security tracker ↗

Release	Package	Fixed in	Advisory
Debian 14	linux	4.7.2-1	—
Debian 13	linux	4.7.2-1	—
Debian 12	linux	4.7.2-1	—

openSUSE

Security tracker ↗

Release	Package	Fixed in	Advisory
openSUSE Tumbleweed	kernel-source	4.8.13-1.1	openSUSE-SU-2024:10128-1

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

wpengfei/CVE-2016-6516-exploit ★ 9 · Dec 7, 2017

An demonstration of how to exploit double-fetch vulnerability CVE-2016-6516

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Advisories 1

openSUSE-SU-2024:10128-1 kernel-debug-4.8.13-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026

Race condition in the ioctl_file_dedupe_range function in fs/ioctl.c in the Linux kernel through 4.7 allows local users to cause a denial o…