Re: [PATCH 1/3] misc: fastrpc: reject oversized DMA allocations

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, Jun 25, 2026 at 10:56:57AM +0200, Yousef Alhouseen wrote:
> FastRPC keeps invoke and mmap buffer sizes in u64 fields, but coherent
> DMA allocation takes a size_t. On 32-bit builds, a size above SIZE_MAX
> can be truncated before allocation while the larger value is still used
> in the message sent to the DSP.
> 
> Reject sizes that cannot fit in size_t before allocating the DMA buffer.
> Also make the inline payload alignment step overflow-aware so a
> near-U64_MAX accumulator cannot wrap before the later bounds checks.
> 
> Signed-off-by: Yousef Alhouseen <alhouseenyousef@gmail.com>
> ---
>  drivers/misc/fastrpc.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 

Are you forgetting to include the tool information that you used to
find/fix all of these issues?  And how are they being tested?

thanks,

greg k-h