stdlib: Fixup mbstowcs NULL __dst handling. [BZ #29279]

commit 464d189b9622932a75302290625de84931656ec0 (origin/master, origin/HEAD)
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date:   Wed Jun 22 08:24:21 2022 -0700

    stdlib: Remove attr_write from mbstows if dst is NULL [BZ: 29265]

Incorrectly called `__mbstowcs_chk` in the NULL __dst case which is
incorrect as in the NULL __dst case we are explicitly skipping
the objsize checks.

As well, remove the `__always_inline` attribute which exists in
`__fortify_function`.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

diff --git a/stdlib/bits/stdlib.h b/stdlib/bits/stdlib.h
index d9c2d822a5ba09105b22dea144d6c6d8c52713fc..de1c3b20f0ba84b6e7c86c0e5cc45994fed97398 100644 (file)
--- a/stdlib/bits/stdlib.h
+++ b/stdlib/bits/stdlib.h
@@ -96,10 +96,10 @@ extern size_t __mbstowcs_chk (wchar_t *__restrict __dst,
                              const char *__restrict __src,
                              size_t __len, size_t __dstlen) __THROW
     __attr_access ((__write_only__, 1, 3)) __attr_access ((__read_only__, 2));
-extern size_t __REDIRECT_NTH (__mbstowcs_chk_nulldst,
+extern size_t __REDIRECT_NTH (__mbstowcs_nulldst,
                              (wchar_t *__restrict __dst,
                               const char *__restrict __src,
-                              size_t __len), mbstowcs_chk)
+                              size_t __len), mbstowcs)
     __attr_access ((__read_only__, 2));
 extern size_t __REDIRECT_NTH (__mbstowcs_alias,
                              (wchar_t *__restrict __dst,
@@ -113,12 +113,12 @@ extern size_t __REDIRECT_NTH (__mbstowcs_chk_warn,
      __warnattr ("mbstowcs called with dst buffer smaller than len "
                 "* sizeof (wchar_t)");
 
-__always_inline __fortify_function size_t
+__fortify_function size_t
 __NTH (mbstowcs (wchar_t *__restrict __dst, const char *__restrict __src,
                 size_t __len))
 {
   if (__builtin_constant_p (__dst == NULL) && __dst == NULL)
-    return __mbstowcs_chk_nulldst (__dst, __src, __len);
+    return __mbstowcs_nulldst (__dst, __src, __len);
   else
     return __glibc_fortify_n (mbstowcs, __len, sizeof (wchar_t),
                              __glibc_objsize (__dst), __dst, __src, __len);