From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:41710 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756423AbbI2NsY (ORCPT ); Tue, 29 Sep 2015 09:48:24 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Trond Myklebust Subject: [PATCH 3.10 17/56] NFS: nfs_set_pgio_error sometimes misses errors Date: Tue, 29 Sep 2015 15:47:05 +0200 Message-Id: <20150929134701.158763863@linuxfoundation.org> In-Reply-To: <20150929134700.376714360@linuxfoundation.org> References: <20150929134700.376714360@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: stable-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit e9ae58aeee8842a50f7e199d602a5ccb2e41a95f upstream. We should ensure that we always set the pgio_header's error field if a READ or WRITE RPC call returns an error. The current code depends on 'hdr->good_bytes' always being initialised to a large value, which is not always done correctly by callers. When this happens, applications may end up missing important errors. Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/pagelist.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -60,8 +60,8 @@ EXPORT_SYMBOL_GPL(nfs_pgheader_init); void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos) { spin_lock(&hdr->lock); - if (pos < hdr->io_start + hdr->good_bytes) { - set_bit(NFS_IOHDR_ERROR, &hdr->flags); + if (!test_and_set_bit(NFS_IOHDR_ERROR, &hdr->flags) + || pos < hdr->io_start + hdr->good_bytes) { clear_bit(NFS_IOHDR_EOF, &hdr->flags); hdr->good_bytes = pos - hdr->io_start; hdr->error = error;