From 36de80740008e6a4a55115b4a92e2059e47c1cba Mon Sep 17 00:00:00 2001
From: Richard Genoud <richard.genoud@gmail.com>
Date: Wed, 27 Sep 2017 14:49:17 +0200
Subject: [PATCH] mtd: nand: atmel: fix buffer overflow in atmel_pmecc_user
Git-commit: 36de80740008e6a4a55115b4a92e2059e47c1cba
Patch-mainline: v4.14-rc3
References: bsc#1051510

When calculating the size needed by struct atmel_pmecc_user *user,
the dmu and delta buffer sizes were forgotten.
This lead to a memory corruption (especially with a large ecc_strength).

Link: http://lkml.kernel.org/r/1506503157.3016.5.camel@gmail.com
Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver")
Cc: stable@vger.kernel.org
Reported-by: Richard Genoud <richard.genoud@gmail.com>
Pointed-at-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/mtd/nand/atmel/pmecc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/atmel/pmecc.c b/drivers/mtd/nand/atmel/pmecc.c
index 146af8218314..8268636675ef 100644
--- a/drivers/mtd/nand/atmel/pmecc.c
+++ b/drivers/mtd/nand/atmel/pmecc.c
@@ -363,7 +363,7 @@ atmel_pmecc_create_user(struct atmel_pmecc *pmecc,
 	size += (req->ecc.strength + 1) * sizeof(u16);
 	/* Reserve space for mu, dmu and delta. */
 	size = ALIGN(size, sizeof(s32));
-	size += (req->ecc.strength + 1) * sizeof(s32);
+	size += (req->ecc.strength + 1) * sizeof(s32) * 3;
 
 	user = kzalloc(size, GFP_KERNEL);
 	if (!user)
-- 
2.16.4