[kernel-hardening] [PATCH v4 2/4] util: Move type casts into is_kernel_rodata

[Kees Cook <keescook@chromium.org>]

From: Emese Revfy <re.emese@gmail.com>

This moves type casts into the is_kernel_rodata() function itself so that
parameters can be marked as "nocapture" in the coming initify gcc plugin.

Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 mm/util.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/mm/util.c b/mm/util.c
index 1a41553db866..5606c6b74eee 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -17,10 +17,10 @@
 
 #include "internal.h"
 
-static inline int is_kernel_rodata(unsigned long addr)
+static inline int is_kernel_rodata(const void *addr)
 {
-	return addr >= (unsigned long)__start_rodata &&
-		addr < (unsigned long)__end_rodata;
+	return (unsigned long)addr >= (unsigned long)__start_rodata &&
+		(unsigned long)addr < (unsigned long)__end_rodata;
 }
 
 /**
@@ -31,7 +31,7 @@ static inline int is_kernel_rodata(unsigned long addr)
  */
 void kfree_const(const void *x)
 {
-	if (!is_kernel_rodata((unsigned long)x))
+	if (!is_kernel_rodata(x))
 		kfree(x);
 }
 EXPORT_SYMBOL(kfree_const);
@@ -68,7 +68,7 @@ EXPORT_SYMBOL(kstrdup);
  */
 const char *kstrdup_const(const char *s, gfp_t gfp)
 {
-	if (is_kernel_rodata((unsigned long)s))
+	if (is_kernel_rodata(s))
 		return s;
 
 	return kstrdup(s, gfp);
-- 
2.7.4