5 files changed, 61 insertions, 6 deletions

diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index 99dfce1cb9..dd47b2698c 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -59,10 +59,12 @@
  * Later we may want to add extra parameter in stringToNode() function
  */
 static bool portable_input = false;
-void
+bool
 set_portable_input(bool value)
 {
+	bool old_portable_input = portable_input;
 	portable_input = value;
+	return old_portable_input;
 }
 #endif /* XCP */
 
diff --git a/src/backend/pgxc/pool/execRemote.c b/src/backend/pgxc/pool/execRemote.c
index 0286337639..2fd23687fc 100644
--- a/src/backend/pgxc/pool/execRemote.c
+++ b/src/backend/pgxc/pool/execRemote.c
@@ -5600,8 +5600,26 @@ ExecInitRemoteSubplan(RemoteSubplan *node, EState *estate, int eflags)
 		rstmt.distributionNodes = node->distributionNodes;
 		rstmt.distributionRestrict = node->distributionRestrict;
 
-		set_portable_output(true);
-		remotestate->subplanstr = nodeToString(&rstmt);
+		/*
+		 * A try-catch block to ensure that we don't leave behind a stale state
+		 * if nodeToString fails for whatever reason.
+		 *
+		 * XXX We should probably rewrite it someday by either passing a
+		 * context to nodeToString() or remembering this information somewhere
+		 * else which gets reset in case of errors. But for now, this seems
+		 * enough.
+		 */
+		PG_TRY();
+		{
+			set_portable_output(true);
+			remotestate->subplanstr = nodeToString(&rstmt);
+		}
+		PG_CATCH();
+		{
+			set_portable_output(false);
+			PG_RE_THROW();
+		}
+		PG_END_TRY();
 		set_portable_output(false);
 
 		/*
diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c
index 524c62d7a0..501cd54b9b 100644
--- a/src/backend/utils/cache/plancache.c
+++ b/src/backend/utils/cache/plancache.c
@@ -2017,9 +2017,26 @@ SetRemoteSubplan(CachedPlanSource *plansource, const char *plan_string)
 
 	/*
 	 * Restore query plan.
+	 *
+	 * A try-catch block to ensure that we don't leave behind a stale state
+	 * if nodeToString fails for whatever reason.
+	 *
+	 * XXX We should probably rewrite it someday by either passing a
+	 * context to nodeToString() or remembering this information somewhere
+	 * else which gets reset in case of errors. But for now, this seems
+	 * enough.
 	 */
-	set_portable_input(true);
-	rstmt = (RemoteStmt *) stringToNode((char *) plan_string);
+	PG_TRY();
+	{
+		set_portable_input(true);
+		rstmt = (RemoteStmt *) stringToNode((char *) plan_string);
+	}
+	PG_CATCH();
+	{
+		set_portable_input(false);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 	set_portable_input(false);
 
 	stmt = makeNode(PlannedStmt);
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index c654213445..7a586f95cf 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -1340,7 +1340,20 @@ RelationBuildDesc(Oid targetRelId, bool insertIt)
 	 * Fetch rules and triggers that affect this relation
 	 */
 	if (relation->rd_rel->relhasrules)
+	{
+		/*
+		 * We could be in the middle of reading a portable input string and get
+		 * called to build the relation descriptor. This might require
+		 * recursive calls to stringToNode (e.g. while reading rules) and those
+		 * must not be done with portable input turned on (because the
+		 * stringified versions are not created with portable output turned
+		 * on). So temporarily reset portable input to false and restore once
+		 * we are done with reading rules.
+		 */
+		bool saved_portable_input = set_portable_input(false);
 		RelationBuildRuleLock(relation);
+		set_portable_input(saved_portable_input);
+	}
 	else
 	{
 		relation->rd_rules = NULL;
@@ -1358,7 +1371,12 @@ RelationBuildDesc(Oid targetRelId, bool insertIt)
 		RelationBuildLocator(relation);
 #endif
 	if (relation->rd_rel->relrowsecurity)
+	{
+		/* See comments near RelationBuildRuleLocok for details */
+		bool saved_portable_input = set_portable_input(false);
 		RelationBuildRowSecurity(relation);
+		set_portable_input(saved_portable_input);
+	}
 	else
 		relation->rd_rsdesc = NULL;
 
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
index 47e55dbb5f..a620f29d0c 100644
--- a/src/include/nodes/nodes.h
+++ b/src/include/nodes/nodes.h
@@ -651,7 +651,7 @@ extern char *bmsToString(const struct Bitmapset *bms);
  * nodes/{readfuncs.c,read.c}
  */
 #ifdef XCP
-extern void set_portable_input(bool value);
+extern bool set_portable_input(bool value);
 #endif
 extern void *stringToNode(char *str);
 extern struct Bitmapset *readBitmapset(void);