Limit recurse depth when parsing mime messages.

Limit to 100 depth to prevent a crash due to stack overflow.  If this
turns out to be too large (or small), I'll adjust it.

1 files changed, 9 insertions, 0 deletions

diff --git a/handler.c b/handler.c
index 35bdd4c4..eb98eeff 100644
--- a/handler.c
+++ b/handler.c
@@ -1770,9 +1770,17 @@ int mutt_body_handler (BODY *b, STATE *s)
   int plaintext = 0;
   handler_t handler = NULL, encrypted_handler = NULL;
   int rc = 0;
+  static unsigned short recurse_level = 0;
 
   int oflags = s->flags;
 
+  if (recurse_level >= 100)
+  {
+    dprint (1, (debugfile, "mutt_body_handler: recurse level too deep. giving up!\n"));
+    return -1;
+  }
+  recurse_level++;
+
   /* first determine which handler to use to process this part */
 
   if (mutt_is_autoview (b))
@@ -1892,6 +1900,7 @@ int mutt_body_handler (BODY *b, STATE *s)
   }
 
 cleanup:
+  recurse_level--;
   s->flags = oflags | (s->flags & MUTT_FIRSTDONE);
   if (rc)
   {