CVE-2022-49320

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

dmaengine: zynqmpdma: In struct zynqmpdmachan fix descsize data type

In zynqmpdmaalloc/freechanresources functions there is a potential overflow in the below expressions.

dmaalloccoherent(chan->dev, (2 * chan->descsize * ZYNQMPDMANUMDESCS), &chan->descpoolp, GFP_KERNEL);

dmafreecoherent(chan->dev,(2 * ZYNQMPDMADESCSIZE(chan) * ZYNQMPDMANUMDESCS), chan->descpoolv, chan->descpoolp);

The arguments descsize and ZYNQMPDMANUMDESCS were 32 bit. Though this overflow condition is not observed but it is a potential problem in the case of 32-bit multiplication. Hence fix it by changing the descsize data type to sizet.

In addition to coverity fix it also reuse ZYNQMPDMADESCSIZE macro in dmaalloc_coherent API argument.

Addresses-Coverity: Event overflowbeforewiden.