It was reported that due to buffer overflow, it is possible for remote TCP endpoint to trigger the opposite TCP endpoint to write to a socket in sequence which causes the ethernet driver to send arbitrary kernel data over the ethernet interface instead of a portion of the intended packet data. Initially this issue was believed to be present in a number of mainline drivers in 3.10.x and 4.4.2 vanilla kernel sources. After further investigation it was found that only [atl2] driver (code in drivers/net/ethernet/atheros/atlx/atl2.c) from the list of suspected drivers is vulnerable. As a result, certain conditions should be met to trigger the issue: - the [atl2] driver and the corresponding network card (which believed to be not so frequently used) should be present on the target system - an application should make such a sequence of calls that a network buffer for the data to be transmitted is scattered - hardware checksumming should be enabled so the packet checksum is correct The above makes this vulnerability less probable to be hit.
Created kernel tracking bugs for this issue: Affects: fedora-all [bug 1318336]
Public via: http://seclists.org/oss-sec/2016/q1/658
Acknowledgments: Name: Justin Yackoski (Cryptonite)
Statement: This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5 as the code with the flaw is not present in the products listed. This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 6 as the suspected driver does not advertise that it has scatter-gather feature, which presence is essential for the flaw. This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 7 and MRG-2, namely the [atl2] Ethernet driver which is the only driver affected. Future Linux kernel updates for the respective releases might address this issue.
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2016:2574 https://rhn.redhat.com/errata/RHSA-2016-2574.html
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2016:2584 https://rhn.redhat.com/errata/RHSA-2016-2584.html