From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_RED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC0CFC4332E for ; Mon, 28 Dec 2020 16:17:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E139207C9 for ; Mon, 28 Dec 2020 16:17:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2440950AbgL1QRl (ORCPT ); Mon, 28 Dec 2020 11:17:41 -0500 Received: from mail.kernel.org ([198.145.29.99]:45006 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387408AbgL1NQ5 (ORCPT ); Mon, 28 Dec 2020 08:16:57 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3410C208BA; Mon, 28 Dec 2020 13:16:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609161401; bh=WxAUeKSKOvzBCHMhXnRw11xywl3lvvwy8E/MCivO0EQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ufaNHVwAjv67ffD17+0sQyMBX24o99jrwfCJQ/7YJ0EJBrl/RvZyr7GXpV8KEhJY3 EPqvdEwHLeDTgtSEHDaAGOiNRnw6gIB1+BKZaQ9/TvkMKbWch+EKXK53k8Q29ErkbZ hJanUC+IIe6EBhVbn+IRQnDidkZpNoK/3V/7TW2M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sebastian Andrzej Siewior , Johan Hovold Subject: [PATCH 4.14 200/242] USB: serial: keyspan_pda: fix dropped unthrottle interrupts Date: Mon, 28 Dec 2020 13:50:05 +0100 Message-Id: <20201228124914.522329825@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124904.654293249@linuxfoundation.org> References: <20201228124904.654293249@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Johan Hovold commit 696c541c8c6cfa05d65aa24ae2b9e720fc01766e upstream. Commit c528fcb116e6 ("USB: serial: keyspan_pda: fix receive sanity checks") broke write-unthrottle handling by dropping well-formed unthrottle-interrupt packets which are precisely two bytes long. This could lead to blocked writers not being woken up when buffer space again becomes available. Instead, stop unconditionally printing the third byte which is (presumably) only valid on modem-line changes. Fixes: c528fcb116e6 ("USB: serial: keyspan_pda: fix receive sanity checks") Cc: stable # 4.11 Acked-by: Sebastian Andrzej Siewior Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/keyspan_pda.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/usb/serial/keyspan_pda.c +++ b/drivers/usb/serial/keyspan_pda.c @@ -176,11 +176,11 @@ static void keyspan_pda_rx_interrupt(str break; case 1: /* status interrupt */ - if (len < 3) { + if (len < 2) { dev_warn(&port->dev, "short interrupt message received\n"); break; } - dev_dbg(&port->dev, "rx int, d1=%d, d2=%d\n", data[1], data[2]); + dev_dbg(&port->dev, "rx int, d1=%d\n", data[1]); switch (data[1]) { case 1: /* modemline change */ break;