CVE-2024-41066

Summary

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 ensure that the skb address is null. If not then warn the user (because this is still a bug that should be patched) and free the old pointer to prevent memleak/tcp problems.

Impact & exploitability

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: https://git.kernel.org/stable/c/0983d288caf984de0202c66641577b739caad561 ↗

Additional information

• NVD record
• https://git.kernel.org/stable/c/0983d288caf984de0202c66641577b739caad561Patch
• https://git.kernel.org/stable/c/16ad1557cae582e79bb82dddd612d9bdfaa11d4cPatch
• https://git.kernel.org/stable/c/267c61c4afed0ff9a2e83462abad3f41d8ca1f06Patch
• https://git.kernel.org/stable/c/e7b75def33eae61ddaad6cb616c517dc3882eb2aPatch