From: Martin K. Petersen <martin.petersen@oracle.com>
Date: Wed, 13 Jun 2012 04:04:30 +0000 (-0400)
Subject: block: Fix bad range check in bio_sector_offset
X-Git-Tag: v2.6.39-400.9.0~516^2~18^2~6
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=5d89ce210ae001bd62f312f0663d797f74a2caa3;p=users%2Fjedix%2Flinux-maple.git

block: Fix bad range check in bio_sector_offset

DM would occasionally end up splitting data integrity-enabled requests
incorrectly. The culprit was a bad range check in bio_sector_offset.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---

diff --git a/fs/bio.c b/fs/bio.c
index 9bfade8a609b..b9a67441ec21 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -1552,8 +1552,8 @@ sector_t bio_sector_offset(struct bio *bio, unsigned short index,
 	sector_sz = queue_logical_block_size(bio->bi_bdev->bd_disk->queue);
 	sectors = 0;
 
-	if (index >= bio->bi_idx)
-		index = bio->bi_vcnt - 1;
+	if (index > bio->bi_vcnt)
+		return 0;
 
 	__bio_for_each_segment(bv, bio, i, 0) {
 		if (i == index) {