Bug #9175 seg fault on 'mysqldump --single-transaction --tab mysql nonexistent'

My code in get_actual_tablename was not checking to make sure SHOW TABLES LIKE % was returning rows.  Now I check that the resultset is not null and has at least 1 row before I process the table.

mysqldump.c:
  Add code to get_actual_tablename() to guard against SHOW TABLES LIKE not returning any rows


client/mysqldump.c:
  Add code to get_actual_tablename() to guard against SHOW TABLES LIKE not returning any rows

1 files changed, 21 insertions, 10 deletions

diff --git a/client/mysqldump.c b/client/mysqldump.c
index 0ff88bcbc73..2a9029244d4 100644
--- a/client/mysqldump.c
+++ b/client/mysqldump.c
@@ -2113,10 +2113,10 @@ static int dump_all_tables_in_db(char *database)
   different case (e.g.  T1 vs t1)
   
   RETURN
-    void
+    int - 0 if a tablename was retrieved.  1 if not
 */
 
-static void get_actual_table_name(const char *old_table_name, 
+static int get_actual_table_name(const char *old_table_name, 
                                   char *new_table_name, 
                                   int buf_size)
 {
@@ -2137,9 +2137,19 @@ static void get_actual_table_name(const char *old_table_name,
   }
 
   tableRes= mysql_store_result( sock );
-  row= mysql_fetch_row( tableRes );
-  strmake(new_table_name, row[0], buf_size-1);
-  mysql_free_result(tableRes);
+  if (tableRes != NULL)
+  {
+	my_ulonglong numRows = mysql_num_rows(tableRes);
+	if (numRows > 0)
+	{
+	  	row= mysql_fetch_row( tableRes );
+	  	strmake(new_table_name, row[0], buf_size-1);
+		return 0;
+	}
+  	mysql_free_result(tableRes);
+	return 1;
+  }
+  return 1;
 }
 
 
@@ -2179,11 +2189,12 @@ static int dump_selected_tables(char *db, char **table_names, int tables)
      char new_table_name[NAME_LEN];
 
      /* the table name passed on commandline may be wrong case */
-     get_actual_table_name( *table_names, new_table_name, sizeof(new_table_name) );
-
-    numrows = getTableStructure(new_table_name, db);
-    if (!dFlag && numrows > 0)
-      dumpTable(numrows, new_table_name);
+     if (!get_actual_table_name( *table_names, new_table_name, sizeof(new_table_name) ))
+     {
+	    numrows = getTableStructure(new_table_name, db);
+	    if (!dFlag && numrows > 0)
+	      dumpTable(numrows, new_table_name);
+     }
     my_free(order_by, MYF(MY_ALLOW_ZERO_PTR));
     order_by= 0;
   }