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Date: Sun, 09 Aug 2009 11:38:31 +0200
From: Roel Kluin <roel.kluin@gmail.com>
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To: David Woodhouse <dwmw2@infradead.org>, linux-mtd@lists.infradead.org,
	Andrew Morton <akpm@linux-foundation.org>
Subject: [PATCH] MTD: Prevent a read from regions[-1]
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If the erase region was found in the first iteration we read from
regions[-1]

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
---
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 349fcbe..a83cfa1 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -453,7 +453,8 @@ static struct mtd_part *add_one_partition(struct mtd_info *master,
 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 			;
 		/* The loop searched for the region _behind_ the first one */
-		i--;
+		if (i > 0)
+			i--;
 
 		/* Pick biggest erasesize */
 		for (; i < max && regions[i].offset < end; i++) {