Commit acaa3f13 authored Mar 20, 2018 by Wei Yongjun Committed by Neil Armstrong Mar 20, 2018

drm/meson: Fix potential NULL dereference in meson_drv_bind_master()



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

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1521555630-29284-1-git-send-email-weiyongjun1@huawei.com

parent ddc389f5

drivers/gpu/drm/meson/meson_drv.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -197,6 +197,8 @@ static int meson_drv_bind_master(struct device *dev, bool has_components)
		priv->io_base = regs;

		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "hhi");
		if (!res)
		return -EINVAL;
		/* Simply ioremap since it may be a shared register zone */
		regs = devm_ioremap(dev, res->start, resource_size(res));
		if (!regs) {
		@@ -213,6 +215,8 @@ static int meson_drv_bind_master(struct device *dev, bool has_components)
		}

		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dmc");
		if (!res)
		return -EINVAL;
		/* Simply ioremap since it may be a shared register zone */
		regs = devm_ioremap(dev, res->start, resource_size(res));
		if (!regs) {