Fix crash in pg_replication_slot_advance

alvherre · alvherre · commit 6f1d723b6359 · 2018-02-19T22:25:27.000-03:00
We were trying to use a LSN variable after releasing its containing slot structure. Reported by: tushar Author: amul sul Reviewed-by: Petr Jelinek, Masahiko Sawada Discussion: https://postgr.es/m/94ba999c-f76a-0423-6523-b8d531dfe4c7@enterprisedb.com
diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c
@@ -480,8 +480,7 @@ pg_replication_slot_advance(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 				 errmsg("cannot move slot to %X/%X, minimum is %X/%X",
 						(uint32) (moveto >> 32), (uint32) moveto,
-						(uint32) (MyReplicationSlot->data.confirmed_flush >> 32),
-						(uint32) (MyReplicationSlot->data.confirmed_flush))));
+						(uint32) (startlsn >> 32), (uint32) startlsn)));
 	}
 
 	if (OidIsValid(MyReplicationSlot->data.database))

Original file line number	Diff line number	Diff line change
`@@ -480,8 +480,7 @@ pg_replication_slot_advance(PG_FUNCTION_ARGS)`
`480`	`480`	`(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),`
`481`	`481`	`errmsg("cannot move slot to %X/%X, minimum is %X/%X",`
`482`	`482`	`(uint32) (moveto >> 32), (uint32) moveto,`
`483`		`- (uint32) (MyReplicationSlot->data.confirmed_flush >> 32),`
`484`		`- (uint32) (MyReplicationSlot->data.confirmed_flush))));`
	`483`	`+ (uint32) (startlsn >> 32), (uint32) startlsn)));`
`485`	`484`	`}`
`486`	`485`
`487`	`486`	`if (OidIsValid(MyReplicationSlot->data.database))`