[PATCH 4.13 091/110] mtd: nand: atmel: fix buffer overflow in atmel_pmecc_user

[Greg Kroah-Hartman]

4.13-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Richard Genoud <richard.genoud@xxxxxxxxx>

commit 36de80740008e6a4a55115b4a92e2059e47c1cba upstream.

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@xxxxxxxxx
Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver")
Reported-by: Richard Genoud <richard.genoud@xxxxxxxxx>
Pointed-at-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Richard Genoud <richard.genoud@xxxxxxxxx>
Reviewed-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

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

--- a/drivers/mtd/nand/atmel/pmecc.c
+++ b/drivers/mtd/nand/atmel/pmecc.c
@@ -363,7 +363,7 @@ atmel_pmecc_create_user(struct atmel_pme
 	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)