bpf: Mark NULL kptr stores precise
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 5.19, 6.6.160, 6.12.114, 6.18.57, 7.2.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Mark NULL kptr stores precise check_map_kptr_access() permits a scalar store into an untrusted kptr field only when the register is known to contain zero. Unlike other verifier checks whose outcome depends on a scalar value, it does not mark that register precise. A state checkpoint reached with an imprecise zero can therefore prune a second path that reaches the store with an arbitrary nonzero scalar. The program can write attacker-controlled bits into the kptr field and load them back as a PTR_TO_BTF_ID. Call mark_chain_precision() before accepting a known-zero register. This forces state equivalence to compare its scalar range and makes the verifier visit and reject a path carrying a nonzero value.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 61df10c7799e27807ad5e459eec9d77cddf8bf45 · fixed in 86a3171c90bfc35a54e9d83cd197ca0d72d2f4e4; From 61df10c7799e27807ad5e459eec9d77cddf8bf45 · fixed in b8b98d3d37908402ff63515fa4d7574235436ea8; From 61df10c7799e27807ad5e459eec9d77cddf8bf45 · fixed in bb667eb575c906f24c707986541a99424c5b07ea; From 61df10c7799e27807ad5e459eec9d77cddf8bf45 · fixed in 86168208737bdd267d92d855d453d1d2f840df19; From 61df10c7799e27807ad5e459eec9d77cddf8bf45 · fixed in ecdc5043794c9184aa8e6c814603899479c46b35; From 5.18.18 · fixed in 5.19
- Linux Linux
5.19
- KernelLinux
From 5.19.0 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.114; From 6.13.0 · fixed in 6.18.57; From 6.19.0 · fixed in 7.2.7