dm integrity: fix memory corruption when tag_size is less than digest size

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: dm integrity: fix memory corruption when tag_size is less than digest size It is possible to set up dm-integrity in such a way that the "tag_size" parameter is less than the actual digest size. In this situation, a part of the digest beyond tag_size is ignored. In this case, dm-integrity would write beyond the end of the ic->recalc_tags array and corrupt memory. The corruption happened in integrity_recalc->integrity_sector_checksum->crypto_shash_final. Fix this corruption by increasing the tags array so that it has enough padding at the end to accomodate the loop in integrity_recalc() being able to write a full digest size for the last member of the tags array.

References

• https://git.kernel.org/stable/c/6a95d91c0b315c965198f6ab7dec7c94129e17e0
• https://git.kernel.org/stable/c/7f84c937222944c03f4615ca4742df6bed0e5adf
• https://git.kernel.org/stable/c/cd02b2687d66f0a8e716384de4b9a0671331f1dc
• https://git.kernel.org/stable/c/6b4bf97587ef6c1927a78934b700204920655123
• https://git.kernel.org/stable/c/4d485cf9b609709e45d5113e6e2b1b01254b2fe9
• https://git.kernel.org/stable/c/08c1af8f1c13bbf210f1760132f4df24d0ed46d6