read_mp4_tag_string() may return a NULL in the pointer so no code should rely

on the pointer being valid unless the return code is checked. This lead to the
year_string being accessed with atoi() even when being NULL => crash. This
fixes FS#7937.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15080 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 10 insertions, 6 deletions

diff --git a/apps/metadata/mp4.c b/apps/metadata/mp4.c
index 6f9383fd5d..4a1fba11c2 100644
--- a/apps/metadata/mp4.c
+++ b/apps/metadata/mp4.c
@@ -402,17 +402,21 @@ static bool read_mp4_tags(int fd, struct mp3entry* id3,
 
         case MP4_cday:
             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
-                &id3->year_string);
+                                &id3->year_string);
  
             /* Try to parse it as a year, for the benefit of the database.
              */
-            id3->year = atoi(id3->year_string);
-
-            if (id3->year < 1900)
+            if(id3->year_string)
             {
-                id3->year = 0;
+                id3->year = atoi(id3->year_string);
+                if (id3->year < 1900)
+                {
+                    id3->year = 0;
+                }
             }
-            
+            else
+                id3->year = 0;
+
             break;
 
         case MP4_gnre: