block: fix integer overflow in __blkdev_sectors_to_bio_pages() (09c2c359) · Commits · 戴 / test

Fix possible integer overflow in __blkdev_sectors_to_bio_pages if sector_t is 32-bit. Signed-off-by:

Mikulas Patocka <mpatocka@redhat.com> Fixes: ("block: Fix __blkdev_issue_zeroout loop") Reviewed-by:

block/blk-lib.c

+2 −2

Original line number	Original line	Diff line number	Diff line
	@@ -269,9 +269,9 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev,
	*/		*/
	static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)		static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
	{		{
	sector_t bytes = (nr_sects << 9) + PAGE_SIZE - 1;		sector_t pages = DIV_ROUND_UP_SECTOR_T(nr_sects, PAGE_SIZE / 512);

	return min(bytes >> PAGE_SHIFT, (sector_t)BIO_MAX_PAGES);		return min(pages, (sector_t)BIO_MAX_PAGES);
	}		}

	/**		/**