elf: Replace `strcpy` call with `memcpy` [BZ #29454]

GCC normally does this optimization for us in
strlen_pass::handle_builtin_strcpy but only for optimized
build. To avoid needing to include strcpy.S in the rtld build to
support the debug build, just do the optimization by hand.

1 files changed, 3 insertions, 2 deletions

diff --git a/elf/dl-cache.c b/elf/dl-cache.c
index 8bbf110..b97c17b 100644
--- a/elf/dl-cache.c
+++ b/elf/dl-cache.c
@@ -509,8 +509,9 @@ _dl_load_cache_lookup (const char *name)
      we are accessing. Therefore we must make the copy of the
      mapping data without using malloc.  */
   char *temp;
-  temp = alloca (strlen (best) + 1);
-  strcpy (temp, best);
+  size_t best_len = strlen (best) + 1;
+  temp = alloca (best_len);
+  memcpy (temp, best, best_len);
   return __strdup (temp);
 }