{"id":"CVE-2025-37913","summary":"net_sched: qfq: 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: qfq: 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 qfq, there won't be a UAF, but the code will add the same\nclassifier to the list twice, which will cause memory corruption.\n\nThis patch checks whether the class was already added to the agg-\u003eactive\nlist (cl_is_active) before doing the addition to cater for the reentrant\ncase.\n\n[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/","modified":"2026-04-02T12:47:37.842038Z","published":"2025-05-20T15:21:44.793Z","related":["MGASA-2025-0182","MGASA-2025-0183","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","SUSE-SU-2026:0473-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/37xxx/CVE-2025-37913.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/005a479540478a820c52de098e5e767e63e36f0a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/041f410aec2c1751ee22b8b73ba05d38c3a6a602"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0aa23e0856b7cedb3c88d8e3d281c212c7e4fbeb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0bf32d6fb1fcbf841bb9945570e0e2a70072c00f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/370218e8ce711684acc4cdd3cc3c6dd7956bc165"},{"type":"WEB","url":"https://git.kernel.org/stable/c/53bc0b55178bd59bdd4bcd16349505cabf54b1a2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a43783119e01849fbf2fe8855634e8989b240cb4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f139f37dcdf34b67f5bf92bc8e0f7f6b3ac63aa4"},{"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-2025-37913.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-37913"},{"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":"041f410aec2c1751ee22b8b73ba05d38c3a6a602"},{"fixed":"005a479540478a820c52de098e5e767e63e36f0a"},{"fixed":"0bf32d6fb1fcbf841bb9945570e0e2a70072c00f"},{"fixed":"0aa23e0856b7cedb3c88d8e3d281c212c7e4fbeb"},{"fixed":"a43783119e01849fbf2fe8855634e8989b240cb4"},{"fixed":"53bc0b55178bd59bdd4bcd16349505cabf54b1a2"},{"fixed":"370218e8ce711684acc4cdd3cc3c6dd7956bc165"},{"fixed":"f139f37dcdf34b67f5bf92bc8e0f7f6b3ac63aa4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-37913.json"}}],"schema_version":"1.7.5"}