Overview
About vulnerability
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.
Details
- Affected product:
- AlmaLinux 9.2 ESU , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+1 more)