[PATCH for v4.9 LTS 03/87] ARM: omap2+: fixing wrong strcat for Non-NULL terminated string

[Levin, Alexander (Sasha Levin)]

From: Maninder Singh <maninder1.s@xxxxxxxxxxx>

[ Upstream commit 5066d5296ff2db20625e5f46e7338872c90c649f ]

Issue caught with static analysis tool:
"Dangerous usage of 'name' (strncpy doesn't always 0-terminate it)"

Use strlcpy _includes_ the NUL terminator, and  strlcat() which ensures
that it won't overflow the buffer.

Reported-by: Maninder Singh <maninder1.s@xxxxxxxxxxx>
Signed-off-by: Vaneet Narang <v.narang@xxxxxxxxxxx>
CC: Russell King <linux@xxxxxxxxxxxxxxx>
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
 arch/arm/mach-omap2/omap_hwmod.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 1052b29697b8..b5c1714ebfdd 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -790,14 +790,14 @@ static int _init_main_clk(struct omap_hwmod *oh)
 	int ret = 0;
 	char name[MOD_CLK_MAX_NAME_LEN];
 	struct clk *clk;
+	static const char modck[] = "_mod_ck";
 
-	/* +7 magic comes from '_mod_ck' suffix */
-	if (strlen(oh->name) + 7 > MOD_CLK_MAX_NAME_LEN)
+	if (strlen(oh->name) >= MOD_CLK_MAX_NAME_LEN - strlen(modck))
 		pr_warn("%s: warning: cropping name for %s\n", __func__,
 			oh->name);
 
-	strncpy(name, oh->name, MOD_CLK_MAX_NAME_LEN - 7);
-	strcat(name, "_mod_ck");
+	strlcpy(name, oh->name, MOD_CLK_MAX_NAME_LEN - strlen(modck));
+	strlcat(name, modck, MOD_CLK_MAX_NAME_LEN);
 
 	clk = clk_get(NULL, name);
 	if (!IS_ERR(clk)) {
-- 
2.11.0