FAILED: patch "[PATCH] smb: client: drain outstanding I/O before truncating on" failed to apply to 7.2-stable tree

The patch below does not apply to the 7.2-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]>.

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-7.2.y
git checkout FETCH_HEAD
git cherry-pick -x 3581f843defa0bb30fd7da1e7dba170465e13a95
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026100630-smoked-amusing-608a@gregkh' --subject-prefix 'PATCH 7.2.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From 3581f843defa0bb30fd7da1e7dba170465e13a95 Mon Sep 17 00:00:00 2001
From: Paulo Alcantara <[email protected]>
Date: Fri, 25 Sep 2026 20:16:09 -0300
Subject: [PATCH] smb: client: drain outstanding I/O before truncating on
O_TRUNC open

cifs_do_truncate() flushes the pagecache with filemap_write_and_wait() before resetting the file size to zero, but that does not wait for direct/async I/O that was already in flight, which can complete after the truncate and reinstate stale data past the new EOF.

Drain outstanding netfs I/O with netfs_wait_for_outstanding_io() before resizing the file.

index 4bcb87610897..11355d6bf89d 100644
@@ -1012,6 +1012,8 @@ static int cifs_do_truncate(const unsigned int xid, struct dentry *dentry)
 	}
 	mapping_set_error(inode->i_mapping, rc);
 
+	netfs_wait_for_outstanding_io(inode);
+
 	cfile = find_writable_file(cinode, FIND_FSUID_ONLY);
 	rc = cifs_file_flush(xid, inode, cfile);
 	if (!rc) {