Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932633AbcDRCoL (ORCPT ); Sun, 17 Apr 2016 22:44:11 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:37077 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932531AbcDRCkU (ORCPT ); Sun, 17 Apr 2016 22:40:20 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Miklos Szeredi , Goldwyn Rodrigues , Trond Myklebust , Theodore Tso , David Howells , Al Viro Subject: [PATCH 4.4 112/137] nfs: use file_dentry() Date: Mon, 18 Apr 2016 11:29:34 +0900 Message-Id: <20160418022514.632445957@linuxfoundation.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <20160418022507.236379264@linuxfoundation.org> References: <20160418022507.236379264@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3124 Lines: 90 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Miklos Szeredi commit be62a1a8fd116f5cd9e53726601f970e16e17558 upstream. NFS may be used as lower layer of overlayfs and accessing f_path.dentry can lead to a crash. Fix by replacing direct access of file->f_path.dentry with the file_dentry() accessor, which will always return a native object. Fixes: 4bacc9c9234c ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay") Signed-off-by: Miklos Szeredi Tested-by: Goldwyn Rodrigues Acked-by: Trond Myklebust Signed-off-by: Theodore Ts'o Cc: David Howells Cc: Al Viro Signed-off-by: Greg Kroah-Hartman --- fs/nfs/dir.c | 6 +++--- fs/nfs/inode.c | 2 +- fs/nfs/nfs4file.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -377,7 +377,7 @@ int nfs_readdir_xdr_filler(struct page * again: timestamp = jiffies; gencount = nfs_inc_attr_generation_counter(); - error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, pages, + error = NFS_PROTO(inode)->readdir(file_dentry(file), cred, entry->cookie, pages, NFS_SERVER(inode)->dtsize, desc->plus); if (error < 0) { /* We requested READDIRPLUS, but the server doesn't grok it */ @@ -560,7 +560,7 @@ int nfs_readdir_page_filler(nfs_readdir_ count++; if (desc->plus != 0) - nfs_prime_dcache(desc->file->f_path.dentry, entry); + nfs_prime_dcache(file_dentry(desc->file), entry); status = nfs_readdir_add_to_array(entry, page); if (status != 0) @@ -864,7 +864,7 @@ static bool nfs_dir_mapping_need_revalid */ static int nfs_readdir(struct file *file, struct dir_context *ctx) { - struct dentry *dentry = file->f_path.dentry; + struct dentry *dentry = file_dentry(file); struct inode *inode = d_inode(dentry); nfs_readdir_descriptor_t my_desc, *desc = &my_desc; --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -927,7 +927,7 @@ int nfs_open(struct inode *inode, struct { struct nfs_open_context *ctx; - ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); + ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode); if (IS_ERR(ctx)) return PTR_ERR(ctx); nfs_file_set_open_context(filp, ctx); --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -26,7 +26,7 @@ static int nfs4_file_open(struct inode *inode, struct file *filp) { struct nfs_open_context *ctx; - struct dentry *dentry = filp->f_path.dentry; + struct dentry *dentry = file_dentry(filp); struct dentry *parent = NULL; struct inode *dir; unsigned openflags = filp->f_flags; @@ -57,7 +57,7 @@ nfs4_file_open(struct inode *inode, stru parent = dget_parent(dentry); dir = d_inode(parent); - ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode); + ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode); err = PTR_ERR(ctx); if (IS_ERR(ctx)) goto out;