CVE-2026-74401

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

dlm: fix add msg handle in send_queue ordered

In a benchmark scenario triggering a lot of requests that triggers a lot

of DLM messages on the network it can be that the mh->seq is not ordered

according the oldest seq number. This ordering is required by

dlmreceiveack as "before(mh->seq, seq)" will stop to check for older

sequence numbers that are ordered in the tail of "node->send_queue".

The side effects of not having it correct ordered regarding

"before(mh->seq, seq)" are refcounting issues and use-after free.

I only was able to reproduce this issue in a experimental DLM branch

and a user space DLM benchmark that uses io_uring. After changing this I

don't experienced any refcounting with the sending buffer issues anymore.