Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-we0-f181.google.com ([74.125.82.181]:61261 "EHLO mail-we0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752386Ab3GIQQt (ORCPT ); Tue, 9 Jul 2013 12:16:49 -0400 Received: by mail-we0-f181.google.com with SMTP id p58so4849726wes.40 for ; Tue, 09 Jul 2013 09:16:47 -0700 (PDT) From: Nadav Shemer To: Trond.Myklebust@netapp.com Cc: linux-nfs@vger.kernel.org Subject: [PATCH] NFSv4: fix open(O_RDONLY|O_TRUNC) returning EBADF Date: Tue, 9 Jul 2013 19:16:45 +0300 Message-Id: <1373386605-18684-1-git-send-email-nadav@tonian.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Move ATTR_OPEN handling from nfs4_proc_setattr into nfs4_do_setattr Signed-off-by: Nadav Shemer --- Hello. I've come across an oddity while testing filesystem coverage My test creates a non-empty file without write permissions and tries to open it with O_RDONLY|O_TRUNC It expects EACCES (and gets that for local filesystems and NFSv3) but gets EBADF on NFSv4 (and v4.1) I found some history on this: In a previous kernel it would just hang due to mishandling the NFS4ERR_OPENMODE exception http://www.spinics.net/lists/linux-nfs/msg28881.html A fix for this was introduced (it specifically tests for NFS4ERR_OPENMODE and returns EACCES for the open() case, EBADF otherwise) http://www.spinics.net/linux/fedora/fedora-kernel/msg03736.html but another patch was also introduced in the same set which seems to break it (it optimizes away the time modification and removes ATTR_OPEN in nfs4_proc_setattr) http://www.spinics.net/linux/fedora/fedora-kernel/msg03732.html By moving the 'Deal with open(O_TRUNC)' bit inside (into nfs4_do_setattr), I got it working again (with no other functional change, as far as I can see) fs/nfs/nfs4proc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 8fbc100..17b9f32 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2180,6 +2180,10 @@ static int nfs4_do_setattr(struct inode *inode, struct rpc_cred *cred, .inode = inode, }; int err; + int is_o_trunc = sattr->ia_valid & ATTR_OPEN; + /* Deal with open(O_TRUNC) */ + if (sattr->ia_valid & ATTR_OPEN) + sattr->ia_valid &= ~(ATTR_MTIME|ATTR_CTIME|ATTR_OPEN); do { err = _nfs4_do_setattr(inode, cred, fattr, sattr, state); switch (err) { @@ -2193,7 +2197,7 @@ static int nfs4_do_setattr(struct inode *inode, struct rpc_cred *cred, } if (state && !(state->state & FMODE_WRITE)) { err = -EBADF; - if (sattr->ia_valid & ATTR_OPEN) + if (is_o_trunc) err = -EACCES; goto out; } @@ -2774,10 +2778,6 @@ nfs4_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr, nfs_fattr_init(fattr); - /* Deal with open(O_TRUNC) */ - if (sattr->ia_valid & ATTR_OPEN) - sattr->ia_valid &= ~(ATTR_MTIME|ATTR_CTIME|ATTR_OPEN); - /* Optimization: if the end result is no change, don't RPC */ if ((sattr->ia_valid & ~(ATTR_FILE)) == 0) return 0; -- 1.7.11.7