{"id":"CVE-2024-57982","summary":"xfrm: state: fix out-of-bounds read during lookup","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: state: fix out-of-bounds read during lookup\n\nlookup and resize can run in parallel.\n\nThe xfrm_state_hash_generation seqlock ensures a retry, but the hash\nfunctions can observe a hmask value that is too large for the new hlist\narray.\n\nrehash does:\n  rcu_assign_pointer(net-\u003exfrm.state_bydst, ndst) [..]\n  net-\u003exfrm.state_hmask = nhashmask;\n\nWhile state lookup does:\n  h = xfrm_dst_hash(net, daddr, saddr, tmpl-\u003ereqid, encap_family);\n  hlist_for_each_entry_rcu(x, net-\u003exfrm.state_bydst + h, bydst) {\n\nThis is only safe in case the update to state_bydst is larger than\nnet-\u003exfrm.xfrm_state_hmask (or if the lookup function gets\nserialized via state spinlock again).\n\nFix this by prefetching state_hmask and the associated pointers.\nThe xfrm_state_hash_generation seqlock retry will ensure that the pointer\nand the hmask will be consistent.\n\nThe existing helpers, like xfrm_dst_hash(), are now unsafe for RCU side,\nadd lockdep assertions to document that they are only safe for insert\nside.\n\nxfrm_state_lookup_byaddr() uses the spinlock rather than RCU.\nAFAICS this is an oversight from back when state lookup was converted to\nRCU, this lock should be replaced with RCU in a future patch.","modified":"2026-04-02T12:25:26.733393Z","published":"2025-02-27T02:07:08.169Z","related":["SUSE-SU-2025:02249-1","SUSE-SU-2025:02254-1","SUSE-SU-2025:02307-1","SUSE-SU-2025:02333-1","SUSE-SU-2025:02334-1","SUSE-SU-2025:02335-1","SUSE-SU-2025:02538-1","SUSE-SU-2025:02923-1","SUSE-SU-2025:20475-1","SUSE-SU-2025:20483-1","SUSE-SU-2025:20493-1","SUSE-SU-2025:20498-1","USN-7521-2"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/57xxx/CVE-2024-57982.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/a16871c7832ea6435abb6e0b58289ae7dcb7e4fc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b86dc510308d7a8955f3f47a4fea4bef887653e4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dd4c2a174994238d55ab54da2545543d36f4e0d0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e952837f3ddb0ff726d5b582aa1aad9aa38d024d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/57xxx/CVE-2024-57982.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-57982"},{"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":"c2f672fc94642bae96821a393f342edcfa9794a6"},{"fixed":"b86dc510308d7a8955f3f47a4fea4bef887653e4"},{"fixed":"a16871c7832ea6435abb6e0b58289ae7dcb7e4fc"},{"fixed":"dd4c2a174994238d55ab54da2545543d36f4e0d0"},{"fixed":"e952837f3ddb0ff726d5b582aa1aad9aa38d024d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-57982.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H"}]}