Linux Kernel Integer Overflow Vulnerability in ECDSA Crypto Component

A vulnerability in the Linux kernel's ECDSA implementation has been addressed, which involved an integer overflow risk in the DIV_ROUND_UP() macro. This issue could arise if the implementation's key_size() callback returned an unusually large value. To mitigate this, a new macro, DIV_ROUND_UP_POW2(), was introduced to safely handle key size values. This macro is now used in critical functions to prevent potential overflows.

Impact

Exploitation of this vulnerability could lead to integer overflow, potentially causing unexpected behavior in the ECDSA cryptographic operations.