[vlc-devel] [PATCH] lib: core: fix arg stack overflow warning

[Francois Cartegnie]

for arg count close to half stack
---
 lib/core.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/lib/core.c b/lib/core.c
index 0178a83d44..e9142807fc 100644
--- a/lib/core.c
+++ b/lib/core.c
@@ -46,10 +46,18 @@ libvlc_instance_t * libvlc_new( int argc, const char *const *argv )
     if (unlikely(p_new == NULL))
         return NULL;
 
-    const char *my_argv[argc + 2];
+    if(unlikely(SIZE_MAX - argc < 2))
+        return NULL;
+
+    if(unlikely(SIZE_MAX / sizeof(char *) < (size_t)argc + 2))
+        return NULL;
+
+    const char **my_argv = malloc( (argc + 2) * sizeof(*my_argv) );
+    if(unlikely(!my_argv))
+        goto error;
+
     my_argv[0] = "libvlc"; /* dummy arg0, skipped by getopt() et al */
-    for( int i = 0; i < argc; i++ )
-         my_argv[i + 1] = argv[i];
+    memcpy( &my_argv[1], argv, argc * sizeof(*argv) );
     my_argv[argc + 1] = NULL; /* C calling conventions require a NULL */
 
     libvlc_int_t *p_libvlc_int = libvlc_InternalCreate();
@@ -62,6 +70,7 @@ libvlc_instance_t * libvlc_new( int argc, const char *const *argv )
         goto error;
     }
 
+    free(my_argv);
     p_new->p_libvlc_int = p_libvlc_int;
     p_new->vlm = NULL;
     p_new->ref_count = 1;
@@ -70,6 +79,7 @@ libvlc_instance_t * libvlc_new( int argc, const char *const *argv )
     return p_new;
 
 error:
+    free (my_argv);
     free (p_new);
     libvlc_threads_deinit ();
     return NULL;
-- 
2.14.3