{"id":"CVE-2026-93138","summary":"bpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux\n\nbpf_get_btf_vmlinux() lazily parses the vmlinux BTF under the\nbpf_verifier_lock, but publishes the result through a plain store\nand re-checks it through a plain lockless load. Nothing orders\nthe stores initializing the struct btf inside btf_parse_vmlinux()\nagainst the store publishing the pointer: On a weakly ordered\narch, a concurrent first-time caller taking the lockless fast\npath could in principle observe the pointer before the parsed\ncontents are visible. The mutex_unlock() does not help such a\nreader given it only synchronizes with a later acquisition of the\nsame lock. Thus, publish the pointer with smp_store_release()\nand read it on the fast path with smp_load_acquire().\n\nAcquire semantics are needed rather than a dependency-ordered\nREAD_ONCE(): btf_parse_vmlinux() also populates globals outside\nthe returned object (e.g. bpf_ctx_convert.t). An address\ndependency would only order accesses performed through the\npointer and not cover other globals.","modified":"2026-09-18T03:47:26.940679386Z","published":"2026-09-17T16:11:38.795Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93138.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2892f3f44bf865c8fb6b6c0960edec4cc91806ee"},{"type":"WEB","url":"https://git.kernel.org/stable/c/86d11c594d60b255b526fa5260f669463fb1a063"},{"type":"WEB","url":"https://git.kernel.org/stable/c/92863e678070f57c17c868e4bfa2441a5c61ad2b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/978524ecfc1c539282df5858de1eec20748c6f74"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a7fe72d780122eb934536f1719abad445f6afdf7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e18a10b39c994f04e1ebd7f8fc042bb1ca8ad053"},{"type":"WEB","url":"https://git.kernel.org/stable/c/eaf302628a78806f66d8224d6ba03fb4d5025de4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f32a4a40bc635be25d6816da4bd91e9e58c31bf3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93138.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93138"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8580ac9404f6240668a026785d7d8856f0530409"},{"fixed":"f32a4a40bc635be25d6816da4bd91e9e58c31bf3"},{"fixed":"a7fe72d780122eb934536f1719abad445f6afdf7"},{"fixed":"e18a10b39c994f04e1ebd7f8fc042bb1ca8ad053"},{"fixed":"978524ecfc1c539282df5858de1eec20748c6f74"},{"fixed":"eaf302628a78806f66d8224d6ba03fb4d5025de4"},{"fixed":"2892f3f44bf865c8fb6b6c0960edec4cc91806ee"},{"fixed":"86d11c594d60b255b526fa5260f669463fb1a063"},{"fixed":"92863e678070f57c17c868e4bfa2441a5c61ad2b"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93138.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.270"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.221"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.157"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.52"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93138.json"}}],"schema_version":"1.9.0"}