openwrt/target/linux/bcm27xx/patches-5.15/950-0857-clk-Test-the-clock-pointer-in-clk_hw_get_name.patch

From f8740e21bb2a6eb11da683901e22fbb6fea80dc8 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Tue, 5 Apr 2022 15:20:27 +0200
Subject: [PATCH] clk: Test the clock pointer in clk_hw_get_name()

Unlike __clk_get_name(), clk_hw_get_name() doesn't test wether passed
clk_hw pointer is NULL or not and dereferences it directly. This can
then lead to NULL pointer dereference.

Let's make sure the pointer isn't NULL before dereferencing it.

Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> # imx8mp
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> # exynos4210, meson g12b
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/clk/clk.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -368,7 +368,7 @@ EXPORT_SYMBOL_GPL(__clk_get_name);
 
 const char *clk_hw_get_name(const struct clk_hw *hw)
 {
-	return hw->core->name;
+	return !hw ? NULL : hw->core->name;
 }
 EXPORT_SYMBOL_GPL(clk_hw_get_name);