Commit af498d7f authored May 12, 2009 by Kazuhisa Ichikawa Committed by Jens Axboe May 12, 2009

block: fix the bio_vec array index out-of-bounds test



Current bio_vec array index out-of-bounds test within
__end_that_request_first() does not seem correct.
It checks bio->bi_idx against bio->bi_vcnt, but the subsequent code
uses idx (which is, bio->bi_idx + next_idx) as the array index into
bio_vec array. This means that the test really make sense only at
the first iteration of !(nr_bytes >=bio->bi_size) case (when next_idx
== zero). Fix this by replacing bio->bi_idx with idx.
(This patch applies to 2.6.30-rc4.)

Signed-off-by: Kazuhisa Ichikawa <ki@epsilou.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

parent a4d7749b

block/blk-core.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1768,10 +1768,10 @@ static int __end_that_request_first(struct request *req, int error,
		} else {
		int idx = bio->bi_idx + next_idx;

		if (unlikely(bio->bi_idx >= bio->bi_vcnt)) {
		if (unlikely(idx >= bio->bi_vcnt)) {
		blk_dump_rq_flags(req, "__end_that");
		printk(KERN_ERR "%s: bio idx %d >= vcnt %d\n",
		__func__, bio->bi_idx, bio->bi_vcnt);
		__func__, idx, bio->bi_vcnt);
		break;
		}