In the Linux kernel, the following vulnerability has been resolved:
keys: fix out-of-bounds read in keyring_get_key_chunk()
For description-level chunks keyring_get_key_chunk() advances the read pointer by level * sizeof(long) past the inline prefix but only bounds-checks the prefix, so a long enough key description is read past its kmemdup(desc, desc_len + 1) allocation. Compute the full byte offset and bounds-check the description against it before reading.
The walk only reaches a description-level chunk when two keys collide through the hash, x, type and domain_tag chunks, so this is reached from an unprivileged add_key(2) with a crafted pair of same-type keys whose index hashes collide; KASAN reports a slab-out-of-bounds read.
References
- https://git.kernel.org/stable/c/3a744838453fb9309ce5a5526d3252e211d60152
- https://git.kernel.org/stable/c/63918731f9ae25b5deb022f118e941e6dddfcef4
- https://git.kernel.org/stable/c/8dba33c1e779d0fb9a2acb31e354cf0fc0229111
- https://git.kernel.org/stable/c/d1933e03e8c74a018550c31a393b79c4d95bff40
- https://git.kernel.org/stable/c/e9417d21a22ad2ec398e78fcf084b717ce92cf2f