hcq/MaxScale
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

MXS-2562: Fix out-of-order error during COM_CHANGE_USER

Browse Source 
If an error is generated while a COM_CHANGE_USER is being done, it would
always use the sequence number 1. To properly handle this case and send
the correct sequence number, the COM_CHANGE_USER progress needs to be
tracked at the session level.

The information needs to be shared between the backend and client
protocols as the final OK to the COM_CHANGE_USER, with the sequence number
3, is the one that the backend server returns. Only after this response
has been received and routed to the client can the COM_CHANGE_USER
processing stop.
This commit is contained in:
Markus Mäkelä
2019-06-27 23:28:46 +03:00
parent 3b6387c952
commit 40f35618ad
4 changed files with 26 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
server/modules/protocol/MySQL/mariadbbackend/mysql_backend.cc
View File

@ -916,6 +916,9 @@ static int gw_read_and_write(DCB* dcb)
*/
GWBUF_DATA(read_buffer)[3] = 0x3;
proto->changing_user = false;
auto s = (MYSQL_session*)session->client_dcb->data;
s->changing_user = false;
}
}

14
server/modules/protocol/MySQL/mariadbclient/mysql_client.cc
View File

@ -1594,7 +1594,15 @@ static int gw_client_hangup_event(DCB* dcb)
errmsg += ": " + extra;
}
modutil_send_mysql_err_packet(dcb, 1, 0, 1927, "08S01", errmsg.c_str());
int seqno = 1;
if (dcb->data && ((MYSQL_session*)dcb->data)->changing_user)
{
// In case a COM_CHANGE_USER is in progress, we need to send the error with the seqno 3
seqno = 3;
}
modutil_send_mysql_err_packet(dcb, seqno, 0, 1927, "08S01", errmsg.c_str());
}
dcb_close(dcb);
}
@ -1797,6 +1805,10 @@ static int route_by_statement(MXS_SESSION* session, uint64_t capabilities, GWBUF
if (!proto->changing_user && proto->current_command == MXS_COM_CHANGE_USER)
{
// Track the COM_CHANGE_USER progress at the session level
auto s = (MYSQL_session*)session->client_dcb->data;
s->changing_user = true;
changed_user = true;
send_auth_switch_request_packet(session->client_dcb);

2
server/modules/protocol/MySQL/mysql_common.cc
View File

@ -38,7 +38,7 @@ uint8_t null_client_sha1[MYSQL_SCRAMBLE_LEN] = "";
MYSQL_session* mysql_session_alloc()
{
MYSQL_session* ses = (MYSQL_session*)MXS_CALLOC(1, sizeof(MYSQL_session));
ses->changing_user = false;
return ses;
}