Re: Fwd: New Defects reported by Coverity Scan for Linux

[H. Peter Anvin]

On 04/12/2014 02:41 PM, Ville Syrjälä wrote:
> On Sat, Apr 12, 2014 at 07:29:29AM -0600, Bjorn Helgaas wrote:
>> FYI, looks like these were added by a4dff76924fe ("x86/gpu: Add Intel
>> graphics stolen memory quirk for gen2 platforms").
> 
> Some of the affected gen2 platforms do support up to 2GB of RAM which
> means that if the sign extension were to happen they could hit this.
> However I believe all gen2 platforms are 32bit which AFAIK makes size_t 
> 32 bits. So looks like we can't hit this in practice..
> 
> But if someone were to change the return type to 64bits we'd
> be in real danger, so I guess it would be better to fix the bug
> anyway.
> 
> -#define KB(x)  ((x) * 1024)
> +#define KB(x)  ((x) * 1024U)
> should be sufficient to eliminate the problem. If someone wants me to
> put that into a real patch and send it out let me know.
> 

Please do, but make it UL (in the Linux kernel context, unsigned long is
always equivalent to size_t/pointer size.)

	-hpa


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/