module: check kernel param length at compile time, not runtime

[linux-2.6-omap-h63xx.git] / include / linux / moduleparam.h

diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h
index ec624381c844e26db58bbdd94eeee9e0b9de6962..1eefe6d61b86f6822f92610ad2acfe6d2b366863 100644 (file)
--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -13,6 +13,9 @@
 #define MODULE_PARAM_PREFIX KBUILD_MODNAME "."
 #endif
 
+/* Chosen so that structs with an unsigned long line up. */
+#define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long))
+
 #ifdef MODULE
 #define ___module_cat(a,b) __mod_ ## a ## b
 #define __module_cat(a,b) ___module_cat(a,b)
@@ -79,7 +82,8 @@ struct kparam_array
 #define __module_param_call(prefix, name, set, get, arg, perm)         \
        /* Default value instead of permissions? */                     \
        static int __param_perm_check_##name __attribute__((unused)) =  \
-       BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2)); \
+       BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2))  \
+       + BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN);   \
        static const char __param_str_##name[] = prefix #name;          \
        static struct kernel_param __moduleparam_const __param_##name   \
        __used                                                          \