Patch "fs: Fix S_NOSEC handling" has been added to the 4.0-stable tree

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

fs: Fix S_NOSEC handling

to the 4.0-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:
fs-fix-s_nosec-handling.patch
and it can be found in the queue-4.0 subdirectory.

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

From: Jan Kara <[email protected]>
Date: Thu, 21 May 2015 16:05:52 +0200
Subject: fs: Fix S_NOSEC handling

From: Jan Kara <[email protected]>

commit 2426f3910069ed47c0cc58559a6d088af7920201 upstream.

file_remove_suid() could mistakenly set S_NOSEC inode bit when root was modifying the file. As a result following writes to the file by ordinary user would avoid clearing suid or sgid bits.

Fix the bug by checking actual mode bits before setting S_NOSEC.

---
 fs/inode.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -1693,8 +1693,8 @@ int file_remove_suid(struct file *file)
 		error = security_inode_killpriv(dentry);
 	if (!error && killsuid)
 		error = __remove_suid(dentry, killsuid);
-	if (!error && (inode->i_sb->s_flags & MS_NOSEC))
-		inode->i_flags |= S_NOSEC;
+	if (!error)
+		inode_has_no_xattr(inode);
 
 	return error;
 }

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

queue-4.0/fs-ufs-restore-s_lock-mutex.patch queue-4.0/fs-ufs-revert-ufs-fix-deadlocks-introduced-by-sb-mutex-merge.patch queue-4.0/fs-fix-s_nosec-handling.patch