Merged revisions 182449 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

........
  r182449 | tilghman | 2009-03-17 00:50:52 -0500 (Tue, 17 Mar 2009) | 7 lines
  
  Fix race in astdb
  The underlying db1 implementation does not fully isolate the pages retrieved
  from astdb, so the lock protecting accesses needs to be extended until the
  copy from the shared memory structure is done.
  (closes issue #14682)
   Reported by: makoto
........


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@182450 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/db.c

@@ -180,10 +180,8 @@ int ast_db_get(const char *family, const char *keys, char *value, int valuelen)
 	memset(value, 0, valuelen);
 	key.data = fullkey;
 	key.size = fullkeylen + 1;
-	
+
 	res = astdb->get(astdb, &key, &data, 0);
-	
-	ast_mutex_unlock(&dblock);
 
 	/* Be sure to NULL terminate our data either way */
 	if (res) {
@@ -200,6 +198,11 @@ int ast_db_get(const char *family, const char *keys, char *value, int valuelen)
 			ast_log(LOG_NOTICE, "Strange, empty value for /%s/%s\n", family, keys);
 		}
 	}
+
+	/* Data is not fully isolated for concurrency, so the lock must be extended
+	 * to after the copy to the output buffer. */
+	ast_mutex_unlock(&dblock);
+
 	return res;
 }