Description
In the Linux kernel, the following vulnerability has been resolved: net_sched: drr: Fix double list add in class with netem as child qdisc As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of drr, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before adding to the list to cover for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/
Product status
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before 5da3aad1a13e7edb8ff0778a444ccf49930313e9
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before 4b07ac06b0a712923255aaf2691637693fc7100d
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before 2968632880f1792007eedd12eeedf7f6e2b7e9f3
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before 4f0ecf50cdf76da95828578a92f130b653ac2fcf
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before db205b92dfe0501e5b92fb7cf00971d0e44ba3eb
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before 26e75716b94d6ff9be5ea07d63675c4d189f30b4
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before ab2248110738d4429668140ad22f530a9ee730e1
37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea (git) before f99a3fbf023e20b626be4b0f042463d598050c9a
5.0
Any version before 5.0
5.4.294 (semver)
5.10.238 (semver)
5.15.182 (semver)
6.1.138 (semver)
6.6.90 (semver)
6.12.28 (semver)
6.14.6 (semver)
6.15 (original_commit_for_fix)
References
lists.debian.org/debian-lts-announce/2025/10/msg00007.html
lists.debian.org/debian-lts-announce/2025/08/msg00010.html
git.kernel.org/...c/5da3aad1a13e7edb8ff0778a444ccf49930313e9
git.kernel.org/...c/4b07ac06b0a712923255aaf2691637693fc7100d
git.kernel.org/...c/2968632880f1792007eedd12eeedf7f6e2b7e9f3
git.kernel.org/...c/4f0ecf50cdf76da95828578a92f130b653ac2fcf
git.kernel.org/...c/db205b92dfe0501e5b92fb7cf00971d0e44ba3eb
git.kernel.org/...c/26e75716b94d6ff9be5ea07d63675c4d189f30b4
git.kernel.org/...c/ab2248110738d4429668140ad22f530a9ee730e1
git.kernel.org/...c/f99a3fbf023e20b626be4b0f042463d598050c9a