From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756671Ab1FCXpB (ORCPT ); Fri, 3 Jun 2011 19:45:01 -0400 Received: from mga01.intel.com ([192.55.52.88]:11551 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755372Ab1FCXoV (ORCPT ); Fri, 3 Jun 2011 19:44:21 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.65,317,1304319600"; d="scan'208";a="13344063" From: Russ Gorby To: Greg Kroah-Hartman , Russ Gorby , linux-kernel@vger.kernel.org Cc: suhail.ahmed@intel.com, russ.gorby@intel.com Subject: [PATCHv2 5/7] tty: n_gsm: Fixed NULL ptr OOPs in tty_write_room() Date: Fri, 3 Jun 2011 16:44:00 -0700 Message-Id: <1307144642-5915-6-git-send-email-russ.gorby@intel.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <[PATCHv2 0/5] N_GSM patchset : 06/03/2011: v2> References: <[PATCHv2 0/5] N_GSM patchset : 06/03/2011: v2> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We saw a case where gsmld_output was called after the MUX was shutdown. In this case gsm->tty was null so tty_write_room(NULL) was called which resulted in an exception. checked for gsm->tty == NULL in gsmld_output() Signed-off-by: Russ Gorby --- drivers/tty/n_gsm.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 22c844d..2908199 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2168,6 +2168,8 @@ EXPORT_SYMBOL_GPL(gsm_alloc_mux); static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len) { + if (!gsm->tty) + return -ENXIO; if (tty_write_room(gsm->tty) < len) { set_bit(TTY_DO_WRITE_WAKEUP, &gsm->tty->flags); return -ENOSPC; -- 1.7.0.4