CVE-2026-64053 (GCVE-0-2026-64053)
Vulnerability from cvelistv5
Published
2026-07-19 15:39
Modified
2026-10-19 20:28
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: 3991657ae7074c3c497bf095093178bed37ea1b4
Version: 3991657ae7074c3c497bf095093178bed37ea1b4
Version: 3991657ae7074c3c497bf095093178bed37ea1b4
Version: 3991657ae7074c3c497bf095093178bed37ea1b4
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