[CF 5615] Corrupted FSM page is not saved after zeroing.

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https://commitfest.postgresql.org/patch/5615

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Patch(es): https://www.postgresql.org/message-id/[email protected]
Author(s): Anton Melnikov

Author: Commitfest Bot

src/backend/storage/freespace/freespace.c

@@ -614,7 +614,10 @@ fsm_readbuf(Relation rel, FSMAddress addr, bool extend)
 	{
 		LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
 		if (PageIsNew(BufferGetPage(buf)))
+		{
 			PageInit(BufferGetPage(buf), BLCKSZ, 0);
+			MarkBufferDirty(buf);
+		}
 		LockBuffer(buf, BUFFER_LOCK_UNLOCK);
 	}
 	return buf;