CVE-2026-93138
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix vmlinux BTF prep race in bpf_get_btf_vmlinux bpf_get_btf_vmlinux() lazily parses the vmlinux BTF under the bpf_verifier_lock, but publishes the result through a plain store and re-checks it through a plain lockless load. Nothing orders the stores initializing the struct btf inside btf_parse_vmlinux() against the store publishing the pointer: On a weakly ordered arch, a concurrent first-time caller taking the lockless fast path could in principle observe the pointer before the parsed contents are visible. The mutex_unlock() does not help such a reader given it only synchronizes with a later acquisition of the same lock. Thus, publish the pointer with smp_store_release() and read it on the fast path with smp_load_acquire(). Acquire semantics are needed rather than a dependency-ordered READ_ONCE(): btf_parse_vmlinux() also populates globals outside the returned object (e.g. bpf_ctx_convert.t). An address dependency would only order accesses performed through the pointer and not cover other globals.
- CVSS 3.1
- 7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 7% of CVEs (scores of 2026-10-25)
- Published
- Modified
- Record from
- the NVD, synced
References
- https://git.kernel.org/stable/c/2892f3f44bf865c8fb6b6c0960edec4cc91806ee
- https://git.kernel.org/stable/c/86d11c594d60b255b526fa5260f669463fb1a063
- https://git.kernel.org/stable/c/92863e678070f57c17c868e4bfa2441a5c61ad2b
- https://git.kernel.org/stable/c/978524ecfc1c539282df5858de1eec20748c6f74
- https://git.kernel.org/stable/c/a7fe72d780122eb934536f1719abad445f6afdf7