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:

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The cxgb3send() functions return NETXMIT 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