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SubjectRe: [usb-gadget-udc] question about null check after calling phys_to_virt() function
Hi Felipe,

Quoting Felipe Balbi <balbi@kernel.org>:

> Hi,
>
> "Gustavo A. R. Silva" <garsilva@embeddedor.com> writes:
>> Hello everybody,
>>
>> While looking into Coverity ID 145958 I ran into the following piece
>> of code at drivers/usb/gadget/udc/amd5536udc.c:852:
>>
>> } else if (i == buf_len) {
>> /* first td */
>> td = (struct udc_data_dma *)phys_to_virt(
>> req->td_data->next);
>> td->status = 0;
>> } else {
>> td = (struct udc_data_dma *)phys_to_virt(last->next);
>> td->status = 0;
>> }
>>
>> if (td)
>> td->bufptr = req->req.dma + i; /* assign buffer */
>> else
>> break;
>>
>> The issue here is that _td_ pointer is being dereferenced before null check.
>>
>> After searching for calls to phys_to_virt() function, I've noticed
>> that is not common at all to test the returned address value.
>>
>> So either the null check at line 862 is not needed or a null check
>> before each td->status = 0; needs to be added.
>
> just remove the previous null check
>

I get it.

Thanks!
--
Gustavo A. R. Silva






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