From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeff Layton , Pavel Shilovsky , Steve French Subject: [PATCH 3.14 099/114] CIFS: Fix async reading on reconnects Date: Mon, 15 Sep 2014 12:26:39 -0700 Message-Id: <20140915192644.517796496@linuxfoundation.org> In-Reply-To: <20140915192641.428509513@linuxfoundation.org> References: <20140915192641.428509513@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pavel Shilovsky commit 038bc961c31b070269ecd07349a7ee2e839d4fec upstream. If we get into read_into_pages() from cifs_readv_receive() and then loose a network, we issue cifs_reconnect that moves all mids to a private list and issue their callbacks. The callback of the async read request sets a mid to retry, frees it and wakes up a process that waits on the rdata completion. After the connection is established we return from read_into_pages() with a short read, use the mid that was freed before and try to read the remaining data from the a newly created socket. Both actions are not what we want to do. In reconnect cases (-EAGAIN) we should not mask off the error with a short read but should return the error code instead. Acked-by: Jeff Layton Signed-off-by: Pavel Shilovsky Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/cifs/file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -2844,7 +2844,7 @@ cifs_uncached_read_into_pages(struct TCP total_read += result; } - return total_read > 0 ? total_read : result; + return total_read > 0 && result != -EAGAIN ? total_read : result; } static ssize_t @@ -3267,7 +3267,7 @@ cifs_readpages_read_into_pages(struct TC total_read += result; } - return total_read > 0 ? total_read : result; + return total_read > 0 && result != -EAGAIN ? total_read : result; } static int cifs_readpages(struct file *file, struct address_space *mapping,