A flaw was found in the CXGB3 kernel driver when the network was considered congested. The kernel would incorrectly misinterpret the congestion as an error condition and incorrectly free/clean up the skb. When the device would then send the skb's queued, these structures would be referenced and may panic the system or allow an attacker to escalate privileges in a use-after-free scenario. From the patch: ---- The cxgb3_*_send() functions return NET_XMIT_ values, which are positive integers values. So don't treat positive return values as an error. ---- Upstream commit: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=67f1aee6f45059fd6b0f5b0ecb2c97ad0451f6b3 CVE assignment: http://seclists.org/oss-sec/2016/q1/311
Statement: This issue affects the Linux kernels as shipped with Red Hat Enterprise Linux 5, 6 and 7 and Red Hat Enterprise MRG 2 and realtime kernels and may be addressed in a future update. This has been rated as having Moderate security impact and is not currently planned to be addressed in future updates in Red Hat Enterprise Linux 5 and 6 . For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
Acknowledgements: Name: Venkatesh Pottem (Red Hat Engineering)
Created kernel tracking bugs for this issue: Affects: fedora-all [bug 1309548]
kernel-4.3.6-201.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.
kernel-4.4.2-301.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.
kernel-4.4.3-201.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.
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