crash_dump: release keyring reference at the correct time
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.18.52, 7.2.6
- 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: crash_dump: release keyring reference at the correct time restore_dm_crypt_keys_to_thread_keyring() gets a reference to the user keyring before restoring the saved dm-crypt keys. The same keyring reference is then passed to add_key_to_keyring() for each saved key, but add_key_to_keyring() drops that reference on every call. This is only balanced when exactly one key is restored. With multiple keys, the keyring reference is dropped too many times and may trigger a refcount underflow or use-after-free. When more than five keys are restored, a refcount underflow/use-after-free warning can be triggered. The early error paths after lookup_user_key() also return without dropping the keyring reference. Keep ownership of the keyring reference in restore_dm_crypt_keys_to_thread_keyring(), drop it once on all exit paths, and make add_key_to_keyring() only use the reference without consuming it.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 62f17d9df6924cf805de5ae970470615c1c8d9f2 · fixed in b0f7343a002f9c8b8378011f60482c76f3216dfd; From 62f17d9df6924cf805de5ae970470615c1c8d9f2 · fixed in ed566979f99c5516cad45a76ae25e2a4928ffb67; From 62f17d9df6924cf805de5ae970470615c1c8d9f2 · fixed in ada2e5a44e99113e08ad9b7b71396c6c572204da
- Linux Linux
6.16
- KernelLinux
From 6.16.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6