In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Remove buffer from list prior to unmap operation fastrpc_req_munmap_impl() is called to unmap any buffer. The buffer is getting removed from the list after it is unmapped from DSP. This can create potential race conditions if multiple threads invoke unmap concurrently, where one thread may remove the entry from the list while another thread's unmap operation is still ongoing. Fix this by removing the buffer entry from the list before calling the unmap operation. If the unmap fails, the entry is re-added to the list so that userspace can retry the unmap, or alternatively, the buffer will be cleaned up during device release when the DSP process is torn down and all DSP-side mappings are freed along with remaining buffers in the list.
https://git.kernel.org/stable/c/fe70329055977fc1e8dc6291318d0dd75470795a
https://git.kernel.org/stable/c/9bf22a7d950cec2d1efeca7f16bb20fcca84c36a
https://git.kernel.org/stable/c/97273624f7b356eaf8261609a75cfcb8738a165a
https://git.kernel.org/stable/c/6102ceb4eab845743ee57acd3863fbd06e93c927
https://git.kernel.org/stable/c/0beaa9bd7eb10d9b5e6352ed5161f3f3bbd4c3c5