irmap: Duplicate handle memory when queueing for predump

With the recent cleanups in fdinfo parsing the memory
allocation policy for entries has changed, thus keeping
a pointer on the entry handle is no longer valid (it
will be freed soon).

Said that -- duplicate the memory for queued irmap work.

https://github.com/xemul/criu/issues/328Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

criu/irmap.c

@@ -311,7 +311,12 @@ int irmap_queue_cache(unsigned int dev, unsigned long ino,
 	ip->dev = dev;
 	ip->ino = ino;
 	ip->fh = *fh;
-	fh->handle = NULL; /* don't free in free_fhandle */
+	ip->fh.handle = xmemdup(fh->handle,
+			FH_ENTRY_SIZES__min_entries * sizeof(uint64_t));
+	if (!ip->fh.handle) {
+		xfree(ip);
+		return -1;
+	}
 
 	pr_debug("Queue %x:%lx for pre-dump\n", dev, ino);