{"id":"CVE-2025-37915","summary":"net_sched: drr: Fix double list add in class with netem as child qdisc","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet_sched: drr: Fix double list add in class with netem as child qdisc\n\nAs described in Gerrard's report [1], there are use cases where a netem\nchild qdisc will make the parent qdisc's enqueue callback reentrant.\nIn the case of drr, there won't be a UAF, but the code will add the same\nclassifier to the list twice, which will cause memory corruption.\n\nIn addition to checking for qlen being zero, this patch checks whether the\nclass was already added to the active_list (cl_is_active) before adding\nto the list to cover for the reentrant case.\n\n[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/","modified":"2026-04-16T04:40:29.095863135Z","published":"2025-05-20T15:21:46.440Z","related":["SUSE-SU-2025:01964-1","SUSE-SU-2025:01965-1","SUSE-SU-2025:02000-1","SUSE-SU-2025:02254-1","SUSE-SU-2025:02307-1","SUSE-SU-2025:02333-1","SUSE-SU-2025:02923-1","SUSE-SU-2025:20408-1","SUSE-SU-2025:20413-1","SUSE-SU-2025:20419-1","SUSE-SU-2025:20421-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37915.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/26e75716b94d6ff9be5ea07d63675c4d189f30b4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2968632880f1792007eedd12eeedf7f6e2b7e9f3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4b07ac06b0a712923255aaf2691637693fc7100d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4f0ecf50cdf76da95828578a92f130b653ac2fcf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5da3aad1a13e7edb8ff0778a444ccf49930313e9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ab2248110738d4429668140ad22f530a9ee730e1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/db205b92dfe0501e5b92fb7cf00971d0e44ba3eb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f99a3fbf023e20b626be4b0f042463d598050c9a"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37915.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-37915"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"37d9cf1a3ce35de3df6f7d209bfb1f50cf188cea"},{"fixed":"5da3aad1a13e7edb8ff0778a444ccf49930313e9"},{"fixed":"4b07ac06b0a712923255aaf2691637693fc7100d"},{"fixed":"2968632880f1792007eedd12eeedf7f6e2b7e9f3"},{"fixed":"4f0ecf50cdf76da95828578a92f130b653ac2fcf"},{"fixed":"db205b92dfe0501e5b92fb7cf00971d0e44ba3eb"},{"fixed":"26e75716b94d6ff9be5ea07d63675c4d189f30b4"},{"fixed":"ab2248110738d4429668140ad22f530a9ee730e1"},{"fixed":"f99a3fbf023e20b626be4b0f042463d598050c9a"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-37915.json"}}],"schema_version":"1.7.5"}