[PATCH v2] mach-omap2: fixing wrong strcat for Non-NULL terminated string

From: Maninder Singh
Date: Thu Dec 01 2016 - 06:03:42 EST


variable name can have Non NULL terminated string after cropping
which may result strcat to fail, and cropping is not
required if (strlen(oh->name) + 8 < MOD_CLK_MAX_NAME_LEN).

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

Signed-off-by: Vaneet Narang <v.narang@xxxxxxxxxxx>
Signed-off-by: Maninder Singh <maninder1.s@xxxxxxxxxxx>
---
v1 -> v2: changed strncpy to strlcpy
arch/arm/mach-omap2/omap_hwmod.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 759e1d4..582b95a 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -742,12 +742,14 @@ static int _init_main_clk(struct omap_hwmod *oh)
char name[MOD_CLK_MAX_NAME_LEN];
struct clk *clk;

- /* +7 magic comes from '_mod_ck' suffix */
- if (strlen(oh->name) + 7 > MOD_CLK_MAX_NAME_LEN)
+ /* +8 magic comes from strlen("_mod_ck") added as suffix */
+ if (strlen(oh->name) + 8 > MOD_CLK_MAX_NAME_LEN) {
pr_warn("%s: warning: cropping name for %s\n", __func__,
oh->name);
+ strlcpy(name, oh->name, MOD_CLK_MAX_NAME_LEN - 7);
+ } else
+ strcpy(name, oh->name);

- strncpy(name, oh->name, MOD_CLK_MAX_NAME_LEN - 7);
strcat(name, "_mod_ck");

clk = clk_get(NULL, name);
--
1.9.1