Re: [alsa-devel] [PATCH] ALSA: usb-audio: fix possible hang and overflow in parse_uac2_sample_rate_range()

At Sun, 8 Jan 2012 07:45:09 -0500, Xi Wang wrote:

On Jan 8, 2012, at 4:09 AM, Takashi Iwai wrote:

...

As of now, I have little time to evaluate, so I might have missed something, but I wonder whether

/* avoid overflow */
if (nr_rates == KMALLOC_MAX_SIZE / sizeof(int))
	break;

is the best way to check. This looks ugly to me. If we need to limit the number of rates, better to define some proper numbers as the upper limit. And then, it should warn, not only breaking loop.

Thanks for looking into this. Yeah, I agree using something like MAX_NR_RATES is better. Is 65535 okay or do we need a larger limit?

It's way too higher than any realistic situation ;) I guess 1000 or such should suffice.

thanks,

Takashi