CVE-2026-64053

Summary

In the Linux kernel, the following vulnerability has been resolved:

block: don't overwrite bip_vcnt in bio_integrity_copy_user()

bio_integrity_add_page() already sets bip_vcnt to 1 for the bounce segment. Overwriting it with nr_vecs breaks bip_vcnt <= bip_max_vcnt on WRITE (bip_max_vcnt is 1), so the gap-merge checks in block/blk.h read past the bip_vec[] flex array. On READ the read is in bounds but lands on a saved user bvec instead of the bounce.

The line was added for split propagation, but bio_integrity_clone() doesn't copy bip_vcnt and BIP_CLONE_FLAGS excludes BIP_COPY_USER.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux3991657ae7074c3c497bf095093178bed37ea1b4 < d18160c9525c63c203656fefd847e94b538cd4a4affected
LinuxLinux3991657ae7074c3c497bf095093178bed37ea1b4 < 0d48654af4d1390c888389206cc13b51b82c30e6affected
LinuxLinux3991657ae7074c3c497bf095093178bed37ea1b4 < 066be1439593a381b1a29663becfcfe0c92363e7affected
LinuxLinux3991657ae7074c3c497bf095093178bed37ea1b4 < 637ad3a56a3b889527d1dacea6fea2a8bd648140affected
LinuxLinux6.11affected
LinuxLinux0 < 6.11unaffected
LinuxLinux6.12.92 <= 6.12.*unaffected
LinuxLinux6.18.34 <= 6.18.*unaffected
LinuxLinux7.0.11 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References