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Date: Fri, 20 May 2011 14:22:25 +0100
From: maxin <john.maxin@nokia.com>
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Subject: Re: [PATCH] drivers: mtd: mtdswap: fix possible null dereference
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Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>, linux-mtd@lists.infradead.org,
	David Woodhouse <dwmw2@infradead.org>
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This patch fixes the possible null dereference of the variable "oinfo"
Thanks to Coverity for spotting this.

Signed-off-by: Maxin B. John <john.maxin@nokia.com>
---
diff --git a/drivers/mtd/mtdswap.c b/drivers/mtd/mtdswap.c
index fed215c..62ddb3a 100644
--- a/drivers/mtd/mtdswap.c
+++ b/drivers/mtd/mtdswap.c
@@ -1450,7 +1450,13 @@ static void mtdswap_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
 	}
 
 	oinfo = mtd->ecclayout;
-	if (!mtd->oobsize || !oinfo || oinfo->oobavail < MTDSWAP_OOBSIZE) {
+	if (!oinfo) {
+		printk(KERN_ERR "%s: mtd%d does not have OOB"
+			"\n", MTDSWAP_PREFIX, mtd->index);
+		return;
+	}
+
+	if (!mtd->oobsize || oinfo->oobavail < MTDSWAP_OOBSIZE) {
 		printk(KERN_ERR "%s: Not enough free bytes in OOB, "
 			"%d available, %zu needed.\n",
 			MTDSWAP_PREFIX, oinfo->oobavail, MTDSWAP_OOBSIZE);