From 87081b2d35057c4919a8a05a7c52fe87845874d5 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 1 Jan 2009 17:12:16 +0000 Subject: Fix an oversight in my patch of a couple weeks ago that ensured a snapshot is available during datatype input in Bind message processing. I put the PopActiveSnapshot() or equivalent just before PortalDefineQuery, which is an unsafe spot for it (in 8.3 and later) because we are carrying a plancache refcount that hasn't yet been assigned to the portal. Any error thrown there would result in leaking the refcount. It's not exactly likely that PopActiveSnapshot would throw an elog, perhaps, but it could happen. Reorder the code and add another comment warning not to do that. --- src/backend/tcop/postgres.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) (limited to 'src/backend/tcop/postgres.c') diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index e43846eedfd..4da47480334 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.562 2008/12/13 02:29:21 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.563 2009/01/01 17:12:16 tgl Exp $ * * NOTES * this is the "main" module of the postgres backend and @@ -1714,12 +1714,11 @@ exec_bind_message(StringInfo input_message) cplan = NULL; } - /* Done with the snapshot used for parameter I/O and parsing/planning */ - if (snapshot_set) - PopActiveSnapshot(); - /* - * Define portal and start execution. + * Now we can define the portal. + * + * DO NOT put any code that could possibly throw an error between the + * above "RevalidateCachedPlan(psrc, false)" call and here. */ PortalDefineQuery(portal, saved_stmt_name, @@ -1728,6 +1727,13 @@ exec_bind_message(StringInfo input_message) plan_list, cplan); + /* Done with the snapshot used for parameter I/O and parsing/planning */ + if (snapshot_set) + PopActiveSnapshot(); + + /* + * And we're ready to start portal execution. + */ PortalStart(portal, params, InvalidSnapshot); /* -- cgit v1.2.3