From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760569AbYEYJHa (ORCPT ); Sun, 25 May 2008 05:07:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753882AbYEYJHW (ORCPT ); Sun, 25 May 2008 05:07:22 -0400 Received: from einhorn.in-berlin.de ([192.109.42.8]:59251 "EHLO einhorn.in-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753751AbYEYJHV (ORCPT ); Sun, 25 May 2008 05:07:21 -0400 X-Envelope-From: stefanr@s5r6.in-berlin.de Date: Sun, 25 May 2008 11:06:55 +0200 (CEST) From: Stefan Richter Subject: [PATCH] firewire: don't respond to broadcast write requests To: linux1394-devel@lists.sourceforge.net cc: linux-kernel@vger.kernel.org Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=us-ascii Content-Disposition: INLINE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Contrary to a comment in the source, request->ack of a broadcast write request can be ACK_PENDING. Hence the existing check is insufficient. Debug dmesg before: AR spd 0 tl 00, ffc0 -> ffff, ack_pending , QW req, fffff0000234 = ffffffff AT spd 0 tl 00, ffff -> ffc0, ack_complete, W resp And the requesting node reports an unsolicited response. Debug dmesg after: AR spd 0 tl 00, ffc0 -> ffff, ack_pending , QW req, fffff0000234 = ffffffff Signed-off-by: Stefan Richter --- drivers/firewire/fw-transaction.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) Index: linux/drivers/firewire/fw-transaction.c =================================================================== --- linux.orig/drivers/firewire/fw-transaction.c +++ linux/drivers/firewire/fw-transaction.c @@ -54,6 +54,9 @@ #define HEADER_GET_DATA_LENGTH(q) (((q) >> 16) & 0xffff) #define HEADER_GET_EXTENDED_TCODE(q) (((q) >> 0) & 0xffff) +#define HEADER_DESTINATION_IS_BROADCAST(q) \ + (((q) & HEADER_DESTINATION(0x3f)) == HEADER_DESTINATION(0x3f)) + #define PHY_CONFIG_GAP_COUNT(gap_count) (((gap_count) << 16) | (1 << 22)) #define PHY_CONFIG_ROOT_ID(node_id) ((((node_id) & 0x3f) << 24) | (1 << 23)) #define PHY_IDENTIFIER(id) ((id) << 30) @@ -604,12 +607,9 @@ allocate_request(struct fw_packet *p) void fw_send_response(struct fw_card *card, struct fw_request *request, int rcode) { - /* - * Broadcast packets are reported as ACK_COMPLETE, so this - * check is sufficient to ensure we don't send response to - * broadcast packets or posted writes. - */ - if (request->ack != ACK_PENDING) { + /* unified transaction or broadcast transaction: don't respond */ + if (request->ack != ACK_PENDING || + HEADER_DESTINATION_IS_BROADCAST(request->request_header[0])) { kfree(request); return; } -- Stefan Richter -=====-==--- -=-= ==--= http://arcgraph.de/sr/