From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Miklos Szeredi Subject: [PATCH 4.6 96/96] vfs: fix deadlock in file_remove_privs() on overlayfs Date: Mon, 8 Aug 2016 21:11:59 +0200 Message-Id: <20160808180248.124257479@linuxfoundation.org> In-Reply-To: <20160808180243.898163389@linuxfoundation.org> References: <20160808180243.898163389@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Miklos Szeredi commit c1892c37769cf89c7e7ba57528ae2ccb5d153c9b upstream. file_remove_privs() is called with inode lock on file_inode(), which proceeds to calling notify_change() on file->f_path.dentry. Which triggers the WARN_ON_ONCE(!inode_is_locked(inode)) in addition to deadlocking later when ovl_setattr tries to lock the underlying inode again. Fix this mess by not mixing the layers, but doing everything on underlying dentry/inode. Signed-off-by: Miklos Szeredi Fixes: 07a2daab49c5 ("ovl: Copy up underlying inode's ->i_mode to overlay inode") Signed-off-by: Greg Kroah-Hartman --- fs/inode.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/fs/inode.c +++ b/fs/inode.c @@ -1739,8 +1739,8 @@ static int __remove_privs(struct dentry */ int file_remove_privs(struct file *file) { - struct dentry *dentry = file->f_path.dentry; - struct inode *inode = d_inode(dentry); + struct dentry *dentry = file_dentry(file); + struct inode *inode = file_inode(file); int kill; int error = 0; @@ -1748,7 +1748,7 @@ int file_remove_privs(struct file *file) if (IS_NOSEC(inode)) return 0; - kill = file_needs_remove_privs(file); + kill = dentry_needs_remove_privs(dentry); if (kill < 0) return kill; if (kill)