INN commit: trunk/nnrpd (post.c)

[INN Commit]

    Date: Sunday, June 14, 2015 @ 03:11:06
  Author: iulius
Revision: 9898

nnrpd: don't strlcpy with equal source/dest

strlcpy with overlapping source & destination has undefined behavior.
(INN's version of the function passes the source and destination to
memcpy, which also has undefined behavior when they overlap.)

Thanks to Richard Kettlewell for the patch.

Modified:
  trunk/nnrpd/post.c

--------+
 post.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Modified: post.c
===================================================================
--- post.c	2015-06-14 10:10:37 UTC (rev 9897)
+++ post.c	2015-06-14 10:11:06 UTC (rev 9898)
@@ -1155,8 +1155,9 @@
 	    if (modgroup)
 		snprintf(idbuff, SMBUF, "(mailed to moderator for %s)",
                          modgroup);
-	    else
-		strlcpy(idbuff, HDR(HDR__MESSAGEID), SMBUF);
+            else if (HDR(HDR__MESSAGEID) != idbuff) {
+                strlcpy(idbuff, HDR(HDR__MESSAGEID), SMBUF);
+            }
 	}
 	if (strncmp(p, "DROP", 4) == 0) {
 	    syslog(L_NOTICE, "%s post failed %s", Client.host, p);
@@ -1206,8 +1207,9 @@
 	return MailArticle(modgroup, article);
     }
 
-    if (idbuff)
-	strlcpy(idbuff, HDR(HDR__MESSAGEID), SMBUF);
+    if (idbuff != NULL && HDR(HDR__MESSAGEID) != idbuff) {
+        strlcpy(idbuff, HDR(HDR__MESSAGEID), SMBUF);
+    }
 
     if (PERMaccessconf->spoolfirst)
 	return Spoolit(article, Error);