From 3512a18cbd8d09e22a790540cb9624c3c49827ba Mon Sep 17 00:00:00 2001
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Date: Thu, 26 Jul 2018 12:11:39 -0500
Subject: [PATCH] mailbox: xgene-slimpro: Fix potential NULL pointer dereference
Git-commit: 3512a18cbd8d09e22a790540cb9624c3c49827ba
Patch-mainline: v4.19-rc1
References: bsc#1051510

There is a potential execution path in which function
platform_get_resource() returns NULL. If this happens,
we will end up having a NULL pointer dereference.

Fix this by replacing devm_ioremap with devm_ioremap_resource,
which has the NULL check and the memory region request.

This code was detected with the help of Coccinelle.

Cc: stable@vger.kernel.org
Fixes: f700e84f417b ("mailbox: Add support for APM X-Gene platform mailbox driver")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/mailbox/mailbox-xgene-slimpro.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/mailbox/mailbox-xgene-slimpro.c b/drivers/mailbox/mailbox-xgene-slimpro.c
index a7040163dd43..b8b2b3533f46 100644
--- a/drivers/mailbox/mailbox-xgene-slimpro.c
+++ b/drivers/mailbox/mailbox-xgene-slimpro.c
@@ -195,9 +195,9 @@ static int slimpro_mbox_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, ctx);
 
 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	mb_base = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
-	if (!mb_base)
-		return -ENOMEM;
+	mb_base = devm_ioremap_resource(&pdev->dev, regs);
+	if (IS_ERR(mb_base))
+		return PTR_ERR(mb_base);
 
 	/* Setup mailbox links */
 	for (i = 0; i < MBOX_CNT; i++) {
-- 
2.18.0