From 9e91af5989df693976bee78a5eadf737f0e18965 Mon Sep 17 00:00:00 2001
From: Andrew Kane <andrew@ankane.org>
Date: Mon, 10 Jun 2024 21:20:54 -0700
Subject: [PATCH] Added checks for invalid indexes - #591

---
 src/hnswutils.c | 3 +++
 src/ivfinsert.c | 3 +++
 src/ivfutils.c  | 6 +++++-
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/hnswutils.c b/src/hnswutils.c
index d3ba911..093e7ef 100644
--- a/src/hnswutils.c
+++ b/src/hnswutils.c
@@ -300,6 +300,9 @@ HnswGetMetaPageInfo(Relation index, int *m, HnswElement * entryPoint)
 	page = BufferGetPage(buf);
 	metap = HnswPageGetMeta(page);
 
+	if (unlikely(metap->magicNumber != HNSW_MAGIC_NUMBER))
+		elog(ERROR, "hnsw index is not valid");
+
 	if (m != NULL)
 		*m = metap->m;
 
diff --git a/src/ivfinsert.c b/src/ivfinsert.c
index fd1ea17..1da4822 100644
--- a/src/ivfinsert.c
+++ b/src/ivfinsert.c
@@ -19,6 +19,9 @@ FindInsertPage(Relation index, Datum *values, BlockNumber *insertPage, ListInfo
 	FmgrInfo   *procinfo;
 	Oid			collation;
 
+	/* Ensure index is valid */
+	IvfflatGetMetaPageInfo(index, NULL, NULL);
+
 	/* Avoid compiler warning */
 	listInfo->blkno = nextblkno;
 	listInfo->offno = FirstOffsetNumber;
diff --git a/src/ivfutils.c b/src/ivfutils.c
index 74a4159..2098a64 100644
--- a/src/ivfutils.c
+++ b/src/ivfutils.c
@@ -170,7 +170,11 @@ IvfflatGetMetaPageInfo(Relation index, int *lists, int *dimensions)
 	page = BufferGetPage(buf);
 	metap = IvfflatPageGetMeta(page);
 
-	*lists = metap->lists;
+	if (unlikely(metap->magicNumber != IVFFLAT_MAGIC_NUMBER))
+		elog(ERROR, "ivfflat index is not valid");
+
+	if (lists != NULL)
+		*lists = metap->lists;
 
 	if (dimensions != NULL)
 		*dimensions = metap->dimensions;