Description
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 dlm_receive_ack 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.
References6
- git.kernel.org/stable/c/482606fea302d8bab86901d7426c3716980d99a8
- git.kernel.org/stable/c/4d45250b1d22960f86d83245be188b16e456218b
- git.kernel.org/stable/c/6369619f1b665f12d8c99cc6ff733c64eb08b22e
- git.kernel.org/stable/c/712714f818d83373847874ab0f8e426be79296cf
- git.kernel.org/stable/c/ae9e534e502a0f48c12baf83608c5de0ff0eab11
- git.kernel.org/stable/c/d2248cb70c070f8f04762872772e155b59016f17
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 54 · as of 11 November 2026
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