FAILED: patch "[PATCH] ovl: set lower layer st_dev only if setting lower st_ino" failed to apply to 4.15-stable tree

The patch below does not apply to the 4.15-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: Amir Goldstein <[email protected]>
Date: Wed, 11 Apr 2018 20:09:29 +0300
Subject: [PATCH] ovl: set lower layer st_dev only if setting lower st_ino

For broken hardlinks, we do not return lower st_ino, so we should also not return lower pseudo st_dev.

index 4689716f23d8..1d75b2e96c96 100644
@@ -118,13 +118,10 @@ int ovl_getattr(const struct path *path, struct kstat *stat,
 			 */
 			if (ovl_test_flag(OVL_INDEX, d_inode(dentry)) ||
 			    (!ovl_verify_lower(dentry->d_sb) &&
-			     (is_dir || lowerstat.nlink == 1)))
+			     (is_dir || lowerstat.nlink == 1))) {
 				stat->ino = lowerstat.ino;
-
-			if (samefs)
-				WARN_ON_ONCE(stat->dev != lowerstat.dev);
-			else
 				stat->dev = ovl_get_pseudo_dev(dentry);
+			}
 		}
 		if (samefs) {
 			/*

Do you take attachments?

Thanks,
Amir.

From 1d43335c9a9c2bedcb4b23011f39cabd26ad9ed3 Mon Sep 17 00:00:00 2001
From: Amir Goldstein <[email protected]>
Date: Wed, 11 Apr 2018 20:09:29 +0300
Subject: [PATCH] ovl: set lower layer st_dev only if setting lower st_ino

[ Upstream commit 9f99e50d460ac7fd5f6c9b97aad0088c28c8656d ]

For broken hardlinks, we do not return lower st_ino, so we should also not return lower pseudo st_dev.

---
 fs/overlayfs/inode.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

index 94d2f8a8b779..0dbbfedef54c 100644
@@ -110,13 +110,10 @@ int ovl_getattr(const struct path *path, struct kstat *stat,
 			 * that the upper hardlink is not broken.
 			 */
 			if (is_dir || lowerstat.nlink == 1 ||
-			    ovl_test_flag(OVL_INDEX, d_inode(dentry)))
+			    ovl_test_flag(OVL_INDEX, d_inode(dentry))) {
 				stat->ino = lowerstat.ino;
-
-			if (samefs)
-				WARN_ON_ONCE(stat->dev != lowerstat.dev);
-			else
 				stat->dev = ovl_get_pseudo_dev(dentry);
+			}
 		}
 		if (samefs) {
 			/*

2.7.4

Yup! Thanks for this, now queued up.

greg k-h