linux-kernel - [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem

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

Date:   Mon, 11 Sep 2017 22:01:01 +0900
From:   Masahiro Yamada <yamada.masahiro@...ionext.com>
To:     Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
Cc:     Keiji Hayashibara <hayashibara.keiji@...ionext.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Jassi Brar <jaswinder.singh@...aro.org>,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        linux-kernel@...r.kernel.org, linux-mediatek@...ts.infradead.org,
        linux-arm-kernel@...ts.infradead.org,
        Matthias Brugger <matthias.bgg@...il.com>
Subject: [PATCH 2/5] nvmem: mtk-efuse: use stack for nvmem_config instead of malloc'ing it

nvmem_register() copies all the members of nvmem_config to
nvmem_device.  So, nvmem_config is one-time use data during
probing.  There is no point to keep it until the driver detach.
Using stack should be no problem because nvmem_config is pretty
small.

Signed-off-by: Masahiro Yamada <yamada.masahiro@...ionext.com>
---

 drivers/nvmem/mtk-efuse.c | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
index 32fd572..fa7a0f6 100644
--- a/drivers/nvmem/mtk-efuse.c
+++ b/drivers/nvmem/mtk-efuse.c
@@ -49,7 +49,7 @@ static int mtk_efuse_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct resource *res;
 	struct nvmem_device *nvmem;
-	struct nvmem_config *econfig;
+	struct nvmem_config econfig = {};
 	void __iomem *base;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -57,19 +57,15 @@ static int mtk_efuse_probe(struct platform_device *pdev)
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
-	econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
-	if (!econfig)
-		return -ENOMEM;
-
-	econfig->stride = 4;
-	econfig->word_size = 4;
-	econfig->reg_read = mtk_reg_read;
-	econfig->reg_write = mtk_reg_write;
-	econfig->size = resource_size(res);
-	econfig->priv = base;
-	econfig->dev = dev;
-	econfig->owner = THIS_MODULE;
-	nvmem = nvmem_register(econfig);
+	econfig.stride = 4;
+	econfig.word_size = 4;
+	econfig.reg_read = mtk_reg_read;
+	econfig.reg_write = mtk_reg_write;
+	econfig.size = resource_size(res);
+	econfig.priv = base;
+	econfig.dev = dev;
+	econfig.owner = THIS_MODULE;
+	nvmem = nvmem_register(&econfig);
 	if (IS_ERR(nvmem))
 		return PTR_ERR(nvmem);
 
-- 
2.7.4