Index: uspace/srv/fs/fat/fat_ops.c
===================================================================
--- uspace/srv/fs/fat/fat_ops.c	(revision 69dc065a8876e194f57d45ecef0aa1ed01aa9b9e)
+++ uspace/srv/fs/fat/fat_ops.c	(revision 4098e388e474a3d5cc6daba81339f5102aa1273b)
@@ -78,5 +78,5 @@
 }
 
-static void fat_node_sync(fat_node_t *node)
+static int fat_node_sync(fat_node_t *node)
 {
 	block_t *b;
@@ -96,5 +96,6 @@
 	rc = _fat_block_get(&b, bs, node->idx->dev_handle, node->idx->pfc,
 	    (node->idx->pdi * sizeof(fat_dentry_t)) / bps, BLOCK_FLAGS_NONE);
-	assert(rc == EOK);
+	if (rc != EOK)
+		return rc;
 
 	d = ((fat_dentry_t *)b->data) + (node->idx->pdi % dps);
@@ -111,5 +112,5 @@
 	b->dirty = true;		/* need to sync block */
 	rc = block_put(b);
-	assert(rc == EOK);
+	return rc;
 }
 
@@ -118,4 +119,5 @@
 	fs_node_t *fn;
 	fat_node_t *nodep;
+	int rc;
 
 	fibril_mutex_lock(&ffn_mutex);
@@ -133,6 +135,8 @@
 		list_remove(&nodep->ffn_link);
 		fibril_mutex_unlock(&ffn_mutex);
-		if (nodep->dirty)
-			fat_node_sync(nodep);
+		if (nodep->dirty) {
+			rc = fat_node_sync(nodep);
+			assert(rc == EOK);
+		}
 		idxp_tmp->nodep = NULL;
 		fibril_mutex_unlock(&nodep->lock);