From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:47866 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752002AbdFLMuE (ORCPT ); Mon, 12 Jun 2017 08:50:04 -0400 Subject: Patch "NFS: Ensure we revalidate attributes before using execute_ok()" has been added to the 4.4-stable tree To: trond.myklebust@primarydata.com, buczek@molgen.mpg.de, gregkh@linuxfoundation.org, pmenzel@molgen.mpg.de Cc: , From: Date: Mon, 12 Jun 2017 14:49:48 +0200 Message-ID: <149727178869111@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled NFS: Ensure we revalidate attributes before using execute_ok() to the 4.4-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: nfs-ensure-we-revalidate-attributes-before-using-execute_ok.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 5c5fc09a1157a11dbe84e6421c3e0b37d05238cb Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 28 Dec 2015 19:30:05 -0500 Subject: NFS: Ensure we revalidate attributes before using execute_ok() From: Trond Myklebust commit 5c5fc09a1157a11dbe84e6421c3e0b37d05238cb upstream. Donald Buczek reports that NFS clients can also report incorrect results for access() due to lack of revalidation of attributes before calling execute_ok(). Looking closely, it seems chdir() is afflicted with the same problem. Fix is to ensure we call nfs_revalidate_inode_rcu() or nfs_revalidate_inode() as appropriate before deciding to trust execute_ok(). Reported-by: Donald Buczek Link: http://lkml.kernel.org/r/1451331530-3748-1-git-send-email-buczek@molgen.mpg.de Signed-off-by: Trond Myklebust Signed-off-by: Paul Menzel Signed-off-by: Greg Kroah-Hartman --- fs/nfs/dir.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -2421,6 +2421,20 @@ int nfs_may_open(struct inode *inode, st } EXPORT_SYMBOL_GPL(nfs_may_open); +static int nfs_execute_ok(struct inode *inode, int mask) +{ + struct nfs_server *server = NFS_SERVER(inode); + int ret; + + if (mask & MAY_NOT_BLOCK) + ret = nfs_revalidate_inode_rcu(server, inode); + else + ret = nfs_revalidate_inode(server, inode); + if (ret == 0 && !execute_ok(inode)) + ret = -EACCES; + return ret; +} + int nfs_permission(struct inode *inode, int mask) { struct rpc_cred *cred; @@ -2470,8 +2484,8 @@ force_lookup: res = PTR_ERR(cred); } out: - if (!res && (mask & MAY_EXEC) && !execute_ok(inode)) - res = -EACCES; + if (!res && (mask & MAY_EXEC)) + res = nfs_execute_ok(inode, mask); dfprintk(VFS, "NFS: permission(%s/%lu), mask=0x%x, res=%d\n", inode->i_sb->s_id, inode->i_ino, mask, res); Patches currently in stable-queue which might be from trond.myklebust@primarydata.com are queue-4.4/nfsd-fix-up-the-supattr_exclcreat-attributes.patch queue-4.4/nfsv4-don-t-perform-cached-access-checks-before-we-ve-opened-the-file.patch queue-4.4/nfs-ensure-we-revalidate-attributes-before-using-execute_ok.patch