kernel/params.c: use scnprintf() instead of sprintf()

For some strings (e.g. version string), they are permitted to be larger
than PAGE_SIZE (although meaningless), so recommend to use scnprintf()
instead of sprintf().

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

diff --git a/kernel/params.c b/kernel/params.c
index ec4299c..e5f8f17 100644 (file)
--- a/kernel/params.c
+++ b/kernel/params.c
@@ -241,7 +241,8 @@ int parse_args(const char *doing,
        }                                                               \
        int param_get_##name(char *buffer, const struct kernel_param *kp) \
        {                                                               \
-               return sprintf(buffer, format, *((type *)kp->arg));     \
+               return scnprintf(buffer, PAGE_SIZE, format,             \
+                               *((type *)kp->arg));                    \
        }                                                               \
        struct kernel_param_ops param_ops_##name = {                    \
                .set = param_set_##name,                                \
@@ -285,7 +286,7 @@ EXPORT_SYMBOL(param_set_charp);
 
 int param_get_charp(char *buffer, const struct kernel_param *kp)
 {
-       return sprintf(buffer, "%s", *((char **)kp->arg));
+       return scnprintf(buffer, PAGE_SIZE, "%s", *((char **)kp->arg));
 }
 EXPORT_SYMBOL(param_get_charp);
 
@@ -829,7 +830,7 @@ ssize_t __modver_version_show(struct module_attribute *mattr,
        struct module_version_attribute *vattr =
                container_of(mattr, struct module_version_attribute, mattr);
 
-       return sprintf(buf, "%s\n", vattr->version);
+       return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
 }
 
 extern const struct module_version_attribute *__start___modver[];