Patch "fuse: invalidate dir dentry after chmod" has been added to the 4.8-stable tree

This is a note to let you know that I've just added the patch titled

fuse: invalidate dir dentry after chmod

to the 4.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
fuse-invalidate-dir-dentry-after-chmod.patch
and it can be found in the queue-4.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Miklos Szeredi <[email protected]>
Date: Sat, 1 Oct 2016 07:32:32 +0200
Subject: fuse: invalidate dir dentry after chmod
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From: Miklos Szeredi <[email protected]>

commit 5e2b8828ff3d79aca8c3a1730652758753205b61 upstream.

Without "default_permissions" the userspace filesystem's lookup operation needs to perform the check for search permission on the directory.

If directory does not allow search for everyone (this is quite rare) then userspace filesystem has to set entry timeout to zero to make sure permissions are always performed.

Changing the mode bits of the directory should also invalidate the (previously cached) dentry to make sure the next lookup will have a chance of updating the timeout, if needed.

---
 fs/fuse/dir.c |   12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

@@ -1702,14 +1702,22 @@ error:
 static int fuse_setattr(struct dentry *entry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(entry);
+	int ret;
 
 	if (!fuse_allow_current_process(get_fuse_conn(inode)))
 		return -EACCES;
 
 	if (attr->ia_valid & ATTR_FILE)
-		return fuse_do_setattr(inode, attr, attr->ia_file);
+		ret = fuse_do_setattr(inode, attr, attr->ia_file);
 	else
-		return fuse_do_setattr(inode, attr, NULL);
+		ret = fuse_do_setattr(inode, attr, NULL);
+
+	if (!ret) {
+		/* Directory mode changed, may need to revalidate access */
+		if (d_is_dir(entry) && (attr->ia_valid & ATTR_MODE))
+			fuse_invalidate_entry_cache(entry);
+	}
+	return ret;
 }
 
 static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,

Patches currently in stable-queue which might be from [email protected] are

queue-4.8/fuse-listxattr-verify-xattr-list.patch queue-4.8/fuse-invalidate-dir-dentry-after-chmod.patch queue-4.8/fuse-fix-killing-sid-in-setattr.patch