CVE-2024-41066

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

ibmvnic: Add tx check to prevent skb leak

Below is a summary of how the driver stores a reference to an skb during

transmit:

tx_buff[free_map[consumer_index]]->skb = new_skb;

free_map[consumer_index] = IBMVNIC_INVALID_MAP;

consumer_index ++;

Where variable data looks like this:

free_map == [4, IBMVNIC_INVALID_MAP, IBMVNIC_INVALID_MAP, 0, 3]

consumer_index^

tx_buff == [skb=null, skb=<ptr>, skb=<ptr>, skb=null, skb=null]

The driver has checks to ensure that free_map[consumer_index] pointed to

a valid index but there was no check to ensure that this index pointed

to an unused/null skb address. So, if, by some chance, our free_map and

tx_buff lists become out of sync then we were previously risking an

skb memory leak. This could then cause tcp congestion control to stop

sending packets, eventually leading to ETIMEDOUT.

Therefore, add a conditional to e

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References