1 files changed, 39 insertions, 11 deletions

diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h
index 494f99e852da..b43f4752304e 100644
--- a/include/linux/moduleparam.h
+++ b/include/linux/moduleparam.h
@@ -42,7 +42,7 @@ struct kernel_param;
  * NOARG - the parameter allows for no argument (foo instead of foo=1)
  */
 enum {
-        KERNEL_PARAM_FL_NOARG = (1 << 0)
+        KERNEL_PARAM_OPS_FL_NOARG = (1 << 0)
 };
 
 struct kernel_param_ops {
@@ -56,11 +56,21 @@ struct kernel_param_ops {
         void (*free)(void *arg);
 };
 
+/*
+ * Flags available for kernel_param
+ *
+ * UNSAFE - the parameter is dangerous and setting it will taint the kernel
+ */
+enum {
+        KERNEL_PARAM_FL_UNSAFE = (1 << 0)
+};
+
 struct kernel_param {
         const char *name;
         const struct kernel_param_ops *ops;
         u16 perm;
-        s16 level;
+        s8 level;
+        u8 flags;
         union {
                 void *arg;
                 const struct kparam_string *str;
@@ -113,6 +123,12 @@ struct kparam_array
         module_param_named(name, name, type, perm)
 
 /**
+ * module_param_unsafe - same as module_param but taints kernel
+ */
+#define module_param_unsafe(name, type, perm)                   \
+        module_param_named_unsafe(name, name, type, perm)
+
+/**
  * module_param_named - typesafe helper for a renamed module/cmdline parameter
  * @name: a valid C identifier which is the parameter name.
  * @value: the actual lvalue to alter.
@@ -129,6 +145,14 @@ struct kparam_array
         __MODULE_PARM_TYPE(name, #type)
 
 /**
+ * module_param_named_unsafe - same as module_param_named but taints kernel
+ */
+#define module_param_named_unsafe(name, value, type, perm)              \
+        param_check_##type(name, &(value));                             \
+        module_param_cb_unsafe(name, &param_ops_##type, &value, perm);  \
+        __MODULE_PARM_TYPE(name, #type)
+
+/**
  * module_param_cb - general callback for a module/cmdline parameter
  * @name: a valid C identifier which is the parameter name.
  * @ops: the set & get operations for this parameter.
@@ -137,7 +161,11 @@ struct kparam_array
  * The ops can have NULL set or get functions.
  */
 #define module_param_cb(name, ops, arg, perm)                                 \
-        __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1)
+        __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, 0)
+
+#define module_param_cb_unsafe(name, ops, arg, perm)                          \
+        __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1,    \
+                            KERNEL_PARAM_FL_UNSAFE)
 
 /**
  * <level>_param_cb - general callback for a module/cmdline parameter
@@ -149,7 +177,7 @@ struct kparam_array
  * The ops can have NULL set or get functions.
  */
 #define __level_param_cb(name, ops, arg, perm, level)                   \
-        __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level)
+        __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level, 0)
 
 #define core_param_cb(name, ops, arg, perm)             \
         __level_param_cb(name, ops, arg, perm, 1)
@@ -184,22 +212,22 @@ struct kparam_array
 
 /* This is the fundamental function for registering boot/module
    parameters. */
-#define __module_param_call(prefix, name, ops, arg, perm, level)        \
+#define __module_param_call(prefix, name, ops, arg, perm, level, flags) \
         /* Default value instead of permissions? */                     \
         static const char __param_str_##name[] = prefix #name; \
         static struct kernel_param __moduleparam_const __param_##name   \
         __used                                                          \
     __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
         = { __param_str_##name, ops, VERIFY_OCTAL_PERMISSIONS(perm),    \
-            level, { arg } }
+            level, flags, { arg } }
 
 /* Obsolete - use module_param_cb() */
 #define module_param_call(name, set, get, arg, perm)                    \
         static struct kernel_param_ops __param_ops_##name =             \
-                { 0, (void *)set, (void *)get };                        \
+                { .flags = 0, (void *)set, (void *)get };               \
         __module_param_call(MODULE_PARAM_PREFIX,                        \
                             name, &__param_ops_##name, arg,             \
-                            (perm) + sizeof(__check_old_set_param(set))*0, -1)
+                            (perm) + sizeof(__check_old_set_param(set))*0, -1, 0)
 
 /* We don't get oldget: it's often a new-style param_get_uint, etc. */
 static inline int
@@ -279,7 +307,7 @@ static inline void __kernel_param_unlock(void)
  */
 #define core_param(name, var, type, perm)                               \
         param_check_##type(name, &(var));                               \
-        __module_param_call("", name, &param_ops_##type, &var, perm, -1)
+        __module_param_call("", name, &param_ops_##type, &var, perm, -1, 0)
 #endif /* !MODULE */
 
 /**
@@ -297,7 +325,7 @@ static inline void __kernel_param_unlock(void)
                 = { len, string };                                      \
         __module_param_call(MODULE_PARAM_PREFIX, name,                  \
                             &param_ops_string,                          \
-                            .str = &__param_string_##name, perm, -1);   \
+                            .str = &__param_string_##name, perm, -1, 0);\
         __MODULE_PARM_TYPE(name, "string")
 
 /**
@@ -444,7 +472,7 @@ extern int param_set_bint(const char *val, const struct kernel_param *kp);
         __module_param_call(MODULE_PARAM_PREFIX, name,                  \
                             &param_array_ops,                           \
                             .arr = &__param_arr_##name,                 \
-                            perm, -1);                                  \
+                            perm, -1, 0);                               \
         __MODULE_PARM_TYPE(name, "array of " #type)
 
 extern struct kernel_param_ops param_array_ops;