Bug#20729: Bad date_format() call makes mysql server crash

    
The problem is that the author used the wrong function to send a warning to the 
user about truncation of data.  push_warning() takes a constant string and 
push_warning_printf() takes a format and variable arguments to fill it.

Since the string we were complaining about contains percent characters, the 
printf() code interprets the "%Y" et c. that the user sends.  That's wrong, and
often causes a crash, especially if the date mentions seconds, "%s".

A alternate fix would be to use  push_warning_printf(..., "%s", warn_buff) .


mysql-test/r/date_formats.result:
  Test that an invalid date doesn't crash the server.  We should get a warning back 
  instead of a dead socket.
mysql-test/t/date_formats.test:
  Test that an invalid date doesn't crash the server.  We should get a warning back 
  instead of a dead socket.
sql/time.cc:
  Don't try to use warn_buf as the start of a varible arguement list to send 
  to a warning-formatted my_vsnprintf() .

1 files changed, 7 insertions, 1 deletions

diff --git a/mysql-test/t/date_formats.test b/mysql-test/t/date_formats.test
index f3d507e69e6..0c227258383 100644
--- a/mysql-test/t/date_formats.test
+++ b/mysql-test/t/date_formats.test
@@ -275,7 +275,6 @@ drop table t1;
 select str_to_date( 1, NULL );
 select str_to_date( NULL, 1 );
 select str_to_date( 1, IF(1=1,NULL,NULL) );
-# End of 4.1 tests
 
 #
 # Bug#11326
@@ -298,3 +297,10 @@ SELECT TIME_FORMAT("12:00:00", '%l %p');
 SELECT TIME_FORMAT("23:00:00", '%l %p');
 SELECT TIME_FORMAT("24:00:00", '%l %p');
 SELECT TIME_FORMAT("25:00:00", '%l %p');
+
+#
+# Bug#20729:  Bad date_format() call makes mysql server crash
+#
+SELECT DATE_FORMAT('%Y-%m-%d %H:%i:%s', 1151414896);
+
+--echo "End of 4.1 tests"