pinctrl: dynamically alloc temp array when parsing dt pinconf options

Allocating the temorary array in pinconf_generic_parse_dt_config on stack
might cause problems later on, when the number of options grows over time.
Therefore also allocate this array dynamically to be on the safe side.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 18 insertions, 6 deletions

diff --git a/drivers/pinctrl/pinconf-generic.c b/drivers/pinctrl/pinconf-generic.c
index ea9da1752252..794dad7d68d8 100644
--- a/drivers/pinctrl/pinconf-generic.c
+++ b/drivers/pinctrl/pinconf-generic.c
@@ -182,7 +182,7 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
                                     unsigned long **configs,
                                     unsigned int *nconfigs)
 {
-        unsigned long cfg[ARRAY_SIZE(dt_params)];
+        unsigned long *cfg;
         unsigned int ncfg = 0;
         int ret;
         int i;
@@ -191,6 +191,11 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
         if (!np)
                 return -EINVAL;
 
+        /* allocate a temporary array big enough to hold one of each option */
+        cfg = kzalloc(sizeof(*cfg) * ARRAY_SIZE(dt_params), GFP_KERNEL);
+        if (!cfg)
+                return -ENOMEM;
+
         for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
                 struct pinconf_generic_dt_params *par = &dt_params[i];
                 ret = of_property_read_u32(np, par->property, &val);
@@ -208,11 +213,13 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
                 ncfg++;
         }
 
+        ret = 0;
+
         /* no configs found at all */
         if (ncfg == 0) {
                 *configs = NULL;
                 *nconfigs = 0;
-                return 0;
+                goto out;
         }
 
         /*
@@ -220,11 +227,16 @@ int pinconf_generic_parse_dt_config(struct device_node *np,
          * found properties.
          */
         *configs = kzalloc(ncfg * sizeof(unsigned long), GFP_KERNEL);
-        if (!*configs)
-                return -ENOMEM;
+        if (!*configs) {
+                ret = -ENOMEM;
+                goto out;
+        }
 
-        memcpy(*configs, &cfg, ncfg * sizeof(unsigned long));
+        memcpy(*configs, cfg, ncfg * sizeof(unsigned long));
         *nconfigs = ncfg;
-        return 0;
+
+out:
+        kfree(cfg);
+        return ret;
 }
 #endif