[PATCH] lib/string.c: Clarify kerndoc for stpcpy()

[Kees Cook]

Fix the language around return values to indicate destination instead of
source.

Reported-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Link: https://lore.kernel.org/lkml/CAK7LNAQvQBhjYgSkvm-dVyNz2Jd2C2qAtfyRk-rngEDfjkc38g
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
This is a fix for lib-stringc-implement-stpcpy.patch in -mm.

Andrew, please note that it would be nice to get this into -rc6
to unbreak the clang builds.

Thanks!
---
 lib/string.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/string.c b/lib/string.c
index 6bd0cf0fb009..32a56436c7eb 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -280,12 +280,12 @@ EXPORT_SYMBOL(strscpy_pad);
  * @src: pointer to the beginning of string being copied from. Must not overlap
  *       dest.
  *
- * stpcpy differs from strcpy in a key way: the return value is the new
- * %NUL-terminated character. (for strcpy, the return value is a pointer to
- * src. This interface is considered unsafe as it doesn't perform bounds
- * checking of the inputs. As such it's not recommended for usage. Instead,
- * its definition is provided in case the compiler lowers other libcalls to
- * stpcpy.
+ * stpcpy differs from strcpy in a key way: the return value is a pointer
+ * to the new %NUL-terminated character in @dest. (For strcpy, the return
+ * value is a pointer to the start of @dest. This interface is considered
+ * unsafe as it doesn't perform bounds checking of the inputs. As such it's
+ * not recommended for usage. Instead, its definition is provided in case
+ * the compiler lowers other libcalls to stpcpy.
  */
 char *stpcpy(char *__restrict__ dest, const char *__restrict__ src);
 char *stpcpy(char *__restrict__ dest, const char *__restrict__ src)
-- 
2.25.1


-- 
Kees Cook