On Thu, Jul 31, 2014 at 01:11:42PM +0300, Boaz Harrosh wrote:

quoted

quoted

quoted

+	if (size < 0)

	if(size < PAGE_SIZE), No?

No, absolutely not.  PAGE_SIZE is unsigned long, which (if I understand
my C integer promotions correctly) means that 'size' gets promoted to
an unsigned long, and we compare them unsigned, so errors will never be
caught by this check.

Good point I agree that you need a cast ie.

 	if(size < (long)PAGE_SIZE)

The reason I'm saying this is because of a bug I actually hit when
playing with partitioning and fdisk, it came out that the last partition's
size was not page aligned, and code that checked for (< 0) crashed because
prd returned the last two sectors of the partition, since your API is sector
based this can happen for you here, before you are memseting a PAGE_SIZE
you need to test there is space, No? 

Not in ext2/ext4.  It requires block size == PAGE_SIZE, so it's never
going to request the last partial block in a partition.

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