FreeTDS Development Group

[Alex Kiesel <alex.kiesel AT document-root.de>]

Hi,

I found that when inserting a row that triggers a foreign key violation
or duplicate row violation, freetds was unable to properly read all data
from the wire.

When such an aforementioned error is triggered the database sends a EED
token which gets processed by tds_process_msg(). When the status byte of
the EED message is set to 1, additional error data follows; freetds
fails to read this data from wire - which appears to let sqsh think it
must read data and thus causing it to segfault.

The attached patch fixes this bug; I'd be glad if it's not too late for
the release...

Greets from Karlsruhe,
-Alex
Index: src/tds/token.c
===================================================================
RCS file: /home/cvs/mirror/freetds/freetds/src/tds/token.c,v
retrieving revision 1.244
diff -u -r1.244 token.c
--- src/tds/token.c	30 Dec 2003 14:45:03 -0000	1.244
+++ src/tds/token.c	10 Jan 2004 16:08:52 -0000
@@ -2319,6 +2319,7 @@
 	int rc;
 	int len;
 	int len_sqlstate;
+	int status;
 	TDSMSGINFO msg_info;
 
 	/* make sure message has been freed */
@@ -2360,9 +2361,10 @@
 		if (strcmp(msg_info.sql_state, "ZZZZZ") == 0)
 			TDS_ZERO_FREE(msg_info.sql_state);
 
+		/* if status = 1, extended error data follows */
+		status = tds_get_byte(tds);
+
 		/* junk status and transaction state */
-		/* TODO if status == 1 clear cur_dyn and param_info ?? */
-		tds_get_byte(tds);
 		tds_get_smallint(tds);
 		break;
 	case TDS_INFO_TOKEN:
@@ -2396,6 +2398,12 @@
 	 * TDS_EED_TOKEN is not being called for me. */
 	if (msg_info.sql_state == NULL)
 		msg_info.sql_state = tds_alloc_lookup_sqlstate(tds, msg_info.msg_number);
+
+
+	/* In case extended error data is sent, we just try to discard it */
+	if (1 == status) {
+		tds_process_trailing_tokens(tds);
+	}
 
 	/* call the msg_handler that was set by an upper layer 
 	 * (dblib, ctlib or some other one).  Call it with the pointer to