Re: [PATCH] usb: fix potential integer overflow in usb_sg_init

[Alan Stern]

On Mon, 18 Jan 2016, Insu Yun wrote:

> If nents value is sufficient large, e.g 0x40000000, 
> then it can overflow size in kmalloc and heap overflow happesns.
> Therefore nents value needs to be checked to prevent overflow.

I don't see why.  You seem to be assuming that failure with -EINVAL is 
better than failure with a heap overflow.  I disagree; a heap overflow 
provides more debugging information to help locate the reason for the 
underlying problem.

Alan Stern