CVE-2016-4805

Use-after-free vulnerability in drivers/net/ppp/ppp_generic.c in the Linux kernel before 4.5.2 allows local users to cause a denial of service (memory corruption and system crash, or spinlock) or possibly have unspecified other impact by removing a network namespace, related to the ppp_register_net_channel and ppp_unregister_channel functions.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1f461dcdd296eecedaffffc6bae2bfa90bd7eb89
• http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00044.html
• http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00052.html
• http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00054.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00000.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00007.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00044.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00055.html
• http://www.debian.org/security/2016/dsa-3607
• http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.5.2
• http://www.openwall.com/lists/oss-security/2016/05/15/2
• http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
• http://www.oracle.com/technetwork/topics/security/ovmbulletinoct2016-3090547.html
• http://www.securityfocus.com/bid/90605
• http://www.securitytracker.com/id/1036763
• http://www.ubuntu.com/usn/USN-3021-1
• http://www.ubuntu.com/usn/USN-3021-2
• https://bugzilla.redhat.com/show_bug.cgi?id=1335803
• https://github.com/torvalds/linux/commit/1f461dcdd296eecedaffffc6bae2bfa90bd7eb89
• http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1f461dcdd296eecedaffffc6bae2bfa90bd7eb89
• http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00044.html
• http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00052.html
• http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00054.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00000.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00007.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00044.html
• http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00055.html
• http://www.debian.org/security/2016/dsa-3607
• http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.5.2
• http://www.openwall.com/lists/oss-security/2016/05/15/2
• http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
• http://www.oracle.com/technetwork/topics/security/ovmbulletinoct2016-3090547.html
• http://www.securityfocus.com/bid/90605
• http://www.securitytracker.com/id/1036763
• http://www.ubuntu.com/usn/USN-3021-1
• http://www.ubuntu.com/usn/USN-3021-2
• https://bugzilla.redhat.com/show_bug.cgi?id=1335803
• https://github.com/torvalds/linux/commit/1f461dcdd296eecedaffffc6bae2bfa90bd7eb89