pinctrl: fix signed vs unsigned conditionals inside pinmux_map_to_setting

pinmux_map_to_setting() uses setting->data.mux.func/group to store the return
code of pinmux_func_name_to_selector/pinctrl_get_group_selector(). However,
struct pinctrl_setting_mux defines these elements as unsigned, resulting in all
error codes getting lost. The conditionals following the assignments will always
evaluate to false thus breaking the error paths.

This bug can be triggered by loading a pinmux group map from the devicetree
with an invalid function/group string.

Signed-off-by: John Crispin <blogic@openwrt.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index fa0357bd88ff638ed28f36ce8c84c9d167a80f6e..7cd0c7d0f2cf7344f7e83a53e0e2d404f4ce5969 100644 (file)
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -329,10 +329,10 @@ int pinmux_map_to_setting(struct pinctrl_map const *map,
                return -EINVAL;
        }
 
-       setting->data.mux.func =
-               pinmux_func_name_to_selector(pctldev, map->data.mux.function);
-       if (setting->data.mux.func < 0)
-               return setting->data.mux.func;
+       ret = pinmux_func_name_to_selector(pctldev, map->data.mux.function);
+       if (ret < 0)
+               return ret;
+       setting->data.mux.func = ret;
 
        ret = pmxops->get_function_groups(pctldev, setting->data.mux.func,
                                          &groups, &num_groups);
@@ -356,9 +356,10 @@ int pinmux_map_to_setting(struct pinctrl_map const *map,
                group = groups[0];
        }
 
-       setting->data.mux.group = pinctrl_get_group_selector(pctldev, group);
-       if (setting->data.mux.group < 0)
-               return setting->data.mux.group;
+       ret = pinctrl_get_group_selector(pctldev, group);
+       if (ret < 0)
+               return ret;
+       setting->data.mux.group = ret;
 
        ret = pctlops->get_group_pins(pctldev, setting->data.mux.group, &pins,
                                      &num_pins);