Patch "ovl: fix missing unlock_rename() in ovl_do_copy_up()" has been added to the 4.13-stable tree

[<gregkh@linuxfoundation.org>]

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

    ovl: fix missing unlock_rename() in ovl_do_copy_up()

to the 4.13-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:
     ovl-fix-missing-unlock_rename-in-ovl_do_copy_up.patch
and it can be found in the queue-4.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 5820dc0888d302ac05f8b91ffdf7e4e53b4fbf53 Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@gmail.com>
Date: Mon, 25 Sep 2017 16:39:55 +0300
Subject: ovl: fix missing unlock_rename() in ovl_do_copy_up()

From: Amir Goldstein <amir73il@gmail.com>

commit 5820dc0888d302ac05f8b91ffdf7e4e53b4fbf53 upstream.

Use the ovl_lock_rename_workdir() helper which requires
unlock_rename() only on lock success.

Fixes: ("fd210b7d67ee ovl: move copy up lock out")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/overlayfs/copy_up.c   |    6 ++----
 fs/overlayfs/dir.c       |   20 --------------------
 fs/overlayfs/overlayfs.h |    1 +
 fs/overlayfs/util.c      |   19 +++++++++++++++++++
 4 files changed, 22 insertions(+), 24 deletions(-)

--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -561,10 +561,8 @@ static int ovl_do_copy_up(struct ovl_cop
 		c->tmpfile = true;
 		err = ovl_copy_up_locked(c);
 	} else {
-		err = -EIO;
-		if (lock_rename(c->workdir, c->destdir) != NULL) {
-			pr_err("overlayfs: failed to lock workdir+upperdir\n");
-		} else {
+		err = ovl_lock_rename_workdir(c->workdir, c->destdir);
+		if (!err) {
 			err = ovl_copy_up_locked(c);
 			unlock_rename(c->workdir, c->destdir);
 		}
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -216,26 +216,6 @@ out_unlock:
 	return err;
 }
 
-static int ovl_lock_rename_workdir(struct dentry *workdir,
-				   struct dentry *upperdir)
-{
-	/* Workdir should not be the same as upperdir */
-	if (workdir == upperdir)
-		goto err;
-
-	/* Workdir should not be subdir of upperdir and vice versa */
-	if (lock_rename(workdir, upperdir) != NULL)
-		goto err_unlock;
-
-	return 0;
-
-err_unlock:
-	unlock_rename(workdir, upperdir);
-err:
-	pr_err("overlayfs: failed to lock workdir+upperdir\n");
-	return -EIO;
-}
-
 static struct dentry *ovl_clear_empty(struct dentry *dentry,
 				      struct list_head *list)
 {
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -234,6 +234,7 @@ bool ovl_inuse_trylock(struct dentry *de
 void ovl_inuse_unlock(struct dentry *dentry);
 int ovl_nlink_start(struct dentry *dentry, bool *locked);
 void ovl_nlink_end(struct dentry *dentry, bool locked);
+int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
 
 static inline bool ovl_is_impuredir(struct dentry *dentry)
 {
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -548,3 +548,22 @@ void ovl_nlink_end(struct dentry *dentry
 		mutex_unlock(&OVL_I(d_inode(dentry))->lock);
 	}
 }
+
+int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)
+{
+	/* Workdir should not be the same as upperdir */
+	if (workdir == upperdir)
+		goto err;
+
+	/* Workdir should not be subdir of upperdir and vice versa */
+	if (lock_rename(workdir, upperdir) != NULL)
+		goto err_unlock;
+
+	return 0;
+
+err_unlock:
+	unlock_rename(workdir, upperdir);
+err:
+	pr_err("overlayfs: failed to lock workdir+upperdir\n");
+	return -EIO;
+}


Patches currently in stable-queue which might be from amir73il@gmail.com are

queue-4.13/ovl-fix-missing-unlock_rename-in-ovl_do_copy_up.patch
queue-4.13/ovl-fix-error-value-printed-in-ovl_lookup_index.patch
queue-4.13/ovl-fix-dput-of-err_ptr-in-ovl_cleanup_index.patch
queue-4.13/ovl-fix-regression-caused-by-exclusive-upper-work-dir-protection.patch
queue-4.13/ovl-fix-dentry-leak-in-ovl_indexdir_cleanup.patch