FAILED: patch "[PATCH] cifs: add revalidation on FSCTL failure in" failed to apply to 6.18-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.18-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 <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 53676a5e28231186c9f56d87b7998b640699bc15
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026102114-sincere-numerate-a8df@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From 53676a5e28231186c9f56d87b7998b640699bc15 Mon Sep 17 00:00:00 2001
From: Frank Sorenson <sorenson@redhat.com>
Date: Sun, 23 Aug 2026 18:26:46 -0500
Subject: [PATCH] cifs: add revalidation on FSCTL failure in
 smb2_duplicate_extents()

smb2_duplicate_extents() has no handling for
FSCTL_DUPLICATE_EXTENTS_TO_FILE failure: when the FSCTL fails, local
inode metadata may be stale from the pre-extension or from concurrent
remote writes, but is never refreshed.

Force revalidation on FSCTL failure and use i_size_read() for the
pre-extension check.

Fixes: cfc63fc8126a ("smb3: fix cached file size problems in duplicate extents (reflink)")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 7d6738ffcb80..bea4876b58cb 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -2218,7 +2218,7 @@ smb2_duplicate_extents(const unsigned int xid,
 			       trgtfile->fid.volatile_fid, tcon->tid,
 			       tcon->ses->Suid, src_off, dest_off, len);
 	inode = d_inode(trgtfile->dentry);
-	if (inode->i_size < dest_off + len) {
+	if (i_size_read(inode) < dest_off + len) {
 		rc = smb2_set_file_size(xid, tcon, trgtfile, dest_off + len, false);
 		if (rc)
 			goto duplicate_extents_out;
@@ -2235,7 +2235,10 @@ smb2_duplicate_extents(const unsigned int xid,
 	if (ret_data_len > 0)
 		cifs_dbg(FYI, "Non-zero response length in duplicate extents\n");
 
-	if (rc == 0) {
+	if (rc) {
+		CIFS_I(inode)->time = 0; /* force reval */
+		cifs_invalidate_cache(inode, 0);
+	} else {
 		qrc = SMB2_query_info(xid, tcon, trgtfile->fid.persistent_fid,
 				      trgtfile->fid.volatile_fid, &file_inf);
 		spin_lock(&inode->i_lock);