CVE-2025-21734

In the Linux kernel, the following vulnerability has been resolved:

misc: fastrpc: Fix copy buffer page size

For non-registered buffer, fastrpc driver copies the buffer and pass it to the remote subsystem. There is a problem with current implementation of page size calculation which is not considering the offset in the calculation. This might lead to passing of improper and out-of-bounds page size which could result in memory issue. Calculate page start and page end using the offset adjusted address instead of absolute address.

Red Hat Enterprise Linux is not affected by this vulnerability because the Qualcomm FastRPC driver is not enabled in supported kernels. This driver provides communication interfaces for specialized Qualcomm DSP subsystems, which are not configured or supported in enterprise environments. Consequently, Red Hat installations do not expose the vulnerable buffer handling logic.