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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 731E1C433EF for ; Thu, 7 Jul 2022 11:34:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235428AbiGGLeD (ORCPT ); Thu, 7 Jul 2022 07:34:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42646 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235385AbiGGLdy (ORCPT ); Thu, 7 Jul 2022 07:33:54 -0400 Received: from mta-64-227.siemens.flowmailer.net (mta-64-227.siemens.flowmailer.net [185.136.64.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE54A30564 for ; Thu, 7 Jul 2022 04:33:52 -0700 (PDT) Received: by mta-64-227.siemens.flowmailer.net with ESMTPSA id 20220707113350cce0cc7fefb8b37d1a for ; Thu, 07 Jul 2022 13:33:51 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm1; d=siemens.com; i=daniel.starke@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc:References:In-Reply-To; bh=dmsPVO/ob5l26R3xUoVk7IKDPFVjQUBwffjZsB2FjME=; b=fuObogHGxaCf7YeIywwKa5Xb2x6mvl0/hoF9lr59apW4GkCU+2bVT63otI8wa2OumikRrI zgNJqEPWYJSghpEz4UjJZ0dY2Y4HEe3XwwQOjDwzUgiAZL66ybOUyuSZguSPwwO0G4AczqyE 7gFuuqdAlJPUCvtv8sOobgf2hYafQ=; From: "D. Starke" To: linux-serial@vger.kernel.org, gregkh@linuxfoundation.org, jirislaby@kernel.org Cc: linux-kernel@vger.kernel.org, Daniel Starke Subject: [PATCH v2 4/4] tty: n_gsm: fix missing corner cases in gsmld_poll() Date: Thu, 7 Jul 2022 13:32:23 +0200 Message-Id: <20220707113223.3685-4-daniel.starke@siemens.com> In-Reply-To: <20220707113223.3685-1-daniel.starke@siemens.com> References: <20220707113223.3685-1-daniel.starke@siemens.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-314044:519-21489:flowmailer Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Daniel Starke gsmld_poll() currently fails to handle the following corner cases correctly: - remote party closed the associated tty Add the missing checks and map those to EPOLLHUP. Reorder the checks to group them by their reaction. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) Check for valid pointer in tty->disc_data has been removed compared to v1. Link: https://lore.kernel.org/all/17759c4b-5858-12bb-4beb-c4a1d58c89ae@kernel.org/ diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 51447ccccbab..caa5c14ed57f 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -3053,12 +3053,15 @@ static __poll_t gsmld_poll(struct tty_struct *tty, struct file *file, poll_wait(file, &tty->read_wait, wait); poll_wait(file, &tty->write_wait, wait); + + if (gsm->dead) + mask |= EPOLLHUP; if (tty_hung_up_p(file)) mask |= EPOLLHUP; + if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) + mask |= EPOLLHUP; if (!tty_is_writelocked(tty) && tty_write_room(tty) > 0) mask |= EPOLLOUT | EPOLLWRNORM; - if (gsm->dead) - mask |= EPOLLHUP; return mask; } -- 2.34.1