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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 7BA54C169C4 for ; Sun, 3 Feb 2019 13:58:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 530192084A for ; Sun, 3 Feb 2019 13:58:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729163AbfBCN6W (ORCPT ); Sun, 3 Feb 2019 08:58:22 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53740 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728340AbfBCNt7 (ORCPT ); Sun, 3 Feb 2019 08:49:59 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqI9k-0003tg-Ee; Sun, 03 Feb 2019 13:49:56 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqI9d-00076r-BH; Sun, 03 Feb 2019 14:49:49 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Thomas Gleixner" , "Eugene Syromiatnikov" , "Al Viro" , "Richard Henderson" , "Kate Stewart" , "Philippe Ombredanne" , "Jiri Slaby" , "Alan Cox" , "H. Peter Anvin" , "Greg Kroah-Hartman" , "Ivan Kokshaysky" , "Cc: Johan Hovold" , "Matt Turner" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 164/305] termios, tty/tty_baudrate.c: fix buffer overrun In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "H. Peter Anvin" commit 991a25194097006ec1e0d2e0814ff920e59e3465 upstream. On architectures with CBAUDEX == 0 (Alpha and PowerPC), the code in tty_baudrate.c does not do any limit checking on the tty_baudrate[] array, and in fact a buffer overrun is possible on both architectures. Add a limit check to prevent that situation. This will be followed by a much bigger cleanup/simplification patch. Signed-off-by: H. Peter Anvin (Intel) Requested-by: Cc: Johan Hovold Cc: Jiri Slaby Cc: Al Viro Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Thomas Gleixner Cc: Kate Stewart Cc: Philippe Ombredanne Cc: Eugene Syromiatnikov Cc: Alan Cox Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.16: adjust filename, context] Signed-off-by: Ben Hutchings --- drivers/tty/tty_ioctl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -327,7 +327,7 @@ speed_t tty_termios_baud_rate(struct kte else cbaud += 15; } - return baud_table[cbaud]; + return cbaud >= n_baud_table ? 0 : baud_table[cbaud]; } EXPORT_SYMBOL(tty_termios_baud_rate); @@ -363,7 +363,7 @@ speed_t tty_termios_input_baud_rate(stru else cbaud += 15; } - return baud_table[cbaud]; + return cbaud >= n_baud_table ? 0 : baud_table[cbaud]; #else return tty_termios_baud_rate(termios); #endif