linux-kernel - [PATCH] memory: jz4780_nemc: Fix potential NULL dereference in jz4780_nemc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 4 Dec 2020 16:31:57 +0800
From:   Zhang Changzhong <zhangchangzhong@...wei.com>
To:     Paul Cercueil <paul@...pouillou.net>,
        Krzysztof Kozlowski <krzk@...nel.org>,
        Zubair Lutfullah Kakakhel <Zubair.Kakakhel@...tec.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Alex Smith <alex.smith@...tec.com>
CC:     Zhang Changzhong <zhangchangzhong@...wei.com>,
        <linux-kernel@...r.kernel.org>
Subject: [PATCH] memory: jz4780_nemc: Fix potential NULL dereference in jz4780_nemc_probe()

platform_get_resource() may fail and return NULL, so we should
better check it's return value to avoid a NULL pointer dereference
a bit later in the code.

This is detected by Coccinelle semantic patch.

@@
expression pdev, res, n, t, e, e1, e2;
@@

res = \(platform_get_resource\|platform_get_resource_byname\)(pdev, t,
n);
+ if (!res)
+   return -EINVAL;
... when != res == NULL
e = devm_ioremap(e1, res->start, e2);

Fixes: 911a88829725 ("memory: jz4780-nemc: driver for the NEMC on JZ4780 SoCs")
Signed-off-by: Zhang Changzhong <zhangchangzhong@...wei.com>
---
 drivers/memory/jz4780-nemc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/memory/jz4780-nemc.c b/drivers/memory/jz4780-nemc.c
index 3ec5cb0..465ea92 100644
--- a/drivers/memory/jz4780-nemc.c
+++ b/drivers/memory/jz4780-nemc.c
@@ -291,6 +291,8 @@ static int jz4780_nemc_probe(struct platform_device *pdev)
 	nemc->dev = dev;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EINVAL;
 
 	/*
 	 * The driver currently only uses the registers up to offset
-- 
2.9.5