FAILED: patch "[PATCH] staging: erofs: add two missing erofs_workgroup_put for" failed to apply to 4.19-stable tree

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 138e1a0990e80db486ab9f6c06bd5c01f9a97999 Mon Sep 17 00:00:00 2001
From: Gao Xiang <[email protected]>
Date: Mon, 19 Aug 2019 18:34:23 +0800
Subject: [PATCH] staging: erofs: add two missing erofs_workgroup_put for
corrupted images

As reported by erofs-utils fuzzer, these error handling path will be entered to handle corrupted images.

Lack of erofs_workgroup_puts will cause unmounting unsuccessfully.

Fix these return values to EFSCORRUPTED as well.

index 87b0c96caf8f..23283c97fd3b 100644
@@ -357,14 +357,16 @@ static struct z_erofs_collection *cllookup(struct z_erofs_collector *clt,
 	cl = z_erofs_primarycollection(pcl);
 	if (unlikely(cl->pageofs != (map->m_la & ~PAGE_MASK))) {
 		DBG_BUGON(1);
-		return ERR_PTR(-EIO);
+		erofs_workgroup_put(grp);
+		return ERR_PTR(-EFSCORRUPTED);
 	}
 
 	length = READ_ONCE(pcl->length);
 	if (length & Z_EROFS_PCLUSTER_FULL_LENGTH) {
 		if ((map->m_llen << Z_EROFS_PCLUSTER_LENGTH_BIT) > length) {
 			DBG_BUGON(1);
-			return ERR_PTR(-EIO);
+			erofs_workgroup_put(grp);
+			return ERR_PTR(-EFSCORRUPTED);
 		}
 	} else {
 		unsigned int llen = map->m_llen << Z_EROFS_PCLUSTER_LENGTH_BIT;