[PATCH] usercopy: Improve comments after reorder

[Kees Cook <keescook@chromium.org>]

This updates the comments to better reflect the order and purpose of
the checks.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
 mm/usercopy.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/mm/usercopy.c b/mm/usercopy.c
index e9e9325f7638..726e570c9b9e 100644
--- a/mm/usercopy.c
+++ b/mm/usercopy.c
@@ -243,7 +243,8 @@ static inline void check_heap_object(const void *ptr, unsigned long n,
 /*
  * Validates that the given object is:
  * - not bogus address
- * - known-safe heap or stack object
+ * - fully contained by stack (or stack frame, when available)
+ * - fully within SLAB object (or object whitelist area, when available)
  * - not in kernel text
  */
 void __check_object_size(const void *ptr, unsigned long n, bool to_user)

-- 
Kees Cook