Return-Path: Received: from mail-pa0-f44.google.com ([209.85.220.44]:35813 "EHLO mail-pa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751042AbbHQSD0 (ORCPT ); Mon, 17 Aug 2015 14:03:26 -0400 Received: by pacgr6 with SMTP id gr6so113278318pac.2 for ; Mon, 17 Aug 2015 11:03:26 -0700 (PDT) From: Trond Myklebust To: linux-nfs@vger.kernel.org Subject: [PATCH] NFS: nfs_set_pgio_error sometimes misses errors Date: Mon, 17 Aug 2015 13:03:23 -0500 Message-Id: <1439834603-6897-1-git-send-email-trond.myklebust@primarydata.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: 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. Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust --- fs/nfs/pagelist.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 4984bbe55ff1..7c5718ba625e 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -77,8 +77,8 @@ 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; -- 2.4.3