stdlib: Avoid -Wuse-after-free in __add_to_environ [BZ #26779]

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This commit is contained in:
Martin Sebor 2022-01-25 17:39:36 -07:00
parent ee52ab25ba
commit 4f20a1dc52
1 changed files with 4 additions and 2 deletions

View File

@ -150,7 +150,9 @@ __add_to_environ (const char *name, const char *value, const char *combined,
{
char **new_environ;
/* We allocated this space; we can extend it. */
/* We allocated this space; we can extend it. Avoid using the raw
reallocated pointer to avoid GCC -Wuse-after-free. */
uintptr_t ip_last_environ = (uintptr_t)last_environ;
new_environ = (char **) realloc (last_environ,
(size + 2) * sizeof (char *));
if (new_environ == NULL)
@ -159,7 +161,7 @@ __add_to_environ (const char *name, const char *value, const char *combined,
return -1;
}
if (__environ != last_environ)
if ((uintptr_t)__environ != ip_last_environ)
memcpy ((char *) new_environ, (char *) __environ,
size * sizeof (char *));