On Thu, Jun 13, 2019 at 10:35:44PM +0200, Geert Uytterhoeven wrote:
> I'm always triggered by the use of min_t() and other casts:
> mmc->max_blk_size and mmc->max_blk_count are both unsigned int.
> dma_max_mapping_size() returns size_t, which can be 64-bit.
>
> 1) Can the multiplication overflow?
> Probably not, as per commit 2a55c1eac7882232 ("mmc: renesas_sdhi:
> prevent overflow for max_req_size"), but I thought I'd better ask.
> 2) In theory, dma_max_mapping_size() can return a number that doesn't
> fit in 32-bit, and will be truncated (to e.g. 0), leading to max_req_size
> is zero?
This really should use a min_t on size_t. Otherwise the patch looks
fine:
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
