CVE-2026-45860

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

netfilter: nf_conncount: increase the connection clean up limit to 64

After the optimization to only perform one GC per jiffy, a new problem

was introduced. If more than 8 new connections are tracked per jiffy the

list won't be cleaned up fast enough possibly reaching the limit

wrongly.

In order to prevent this issue, only skip the GC if it was already

triggered during the same jiffy and the increment is lower than the

clean up limit. In addition, increase the clean up limit to 64

connections to avoid triggering GC too often and do more effective GCs.

This has been tested using a HTTP server and several

performance tools while having nft_connlimit/xt_connlimit or OVS limit

configured.

Output of slowhttptest + OVS limit at 52000 connections:

slow HTTP test status on 340th second:

initializing: 0

pending: 432

connected: 51998

error: 0

closed: 0

service available: YES