[PATCH] phy: ocelot-serdes: fix out-of-bounds read

From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
To: Kishon Vijay Abraham I <kishon@ti.com>,
	Quentin Schulz <quentin.schulz@bootlin.com>,
	"David S. Miller" <davem@davemloft.net>
Cc: linux-kernel@vger.kernel.org,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>
Subject: [PATCH] phy: ocelot-serdes: fix out-of-bounds read
Date: Mon, 8 Oct 2018 20:06:49 +0200	[thread overview]
Message-ID: <20181008180649.GA9152@embeddedor.com> (raw)

Currently, there is an out-of-bounds read on array ctrl->phys,
once variable i reaches the maximum array size of SERDES_MAX
in the for loop.

Fix this by changing the condition in the for loop from
i <= SERDES_MAX to i < SERDES_MAX.

Addresses-Coverity-ID: 1473966 ("Out-of-bounds read")
Addresses-Coverity-ID: 1473959 ("Out-of-bounds read")
Fixes: 51f6b410fc22 ("phy: add driver for Microsemi Ocelot SerDes muxing")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 drivers/phy/mscc/phy-ocelot-serdes.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/phy/mscc/phy-ocelot-serdes.c b/drivers/phy/mscc/phy-ocelot-serdes.c
index 8936abd..c4eee3a 100644
--- a/drivers/phy/mscc/phy-ocelot-serdes.c
+++ b/drivers/phy/mscc/phy-ocelot-serdes.c
@@ -206,7 +206,7 @@ static struct phy *serdes_simple_xlate(struct device *dev,
 	port = args->args[0];
 	idx = args->args[1];
 
-	for (i = 0; i <= SERDES_MAX; i++) {
+	for (i = 0; i < SERDES_MAX; i++) {
 		struct serdes_macro *macro = phy_get_drvdata(ctrl->phys[i]);
 
 		if (idx != macro->idx)
@@ -260,7 +260,7 @@ static int serdes_probe(struct platform_device *pdev)
 	if (!ctrl->regs)
 		return -ENODEV;
 
-	for (i = 0; i <= SERDES_MAX; i++) {
+	for (i = 0; i < SERDES_MAX; i++) {
 		ret = serdes_phy_create(ctrl, i, &ctrl->phys[i]);
 		if (ret)
 			return ret;
-- 
2.7.4

