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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 0FC30C43441 for ; Mon, 19 Nov 2018 16:35:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C775C208E3 for ; Mon, 19 Nov 2018 16:35:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="c8ksvzKg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C775C208E3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731641AbeKTC72 (ORCPT ); Mon, 19 Nov 2018 21:59:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:58938 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730350AbeKTC72 (ORCPT ); Mon, 19 Nov 2018 21:59:28 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EF72220C01; Mon, 19 Nov 2018 16:35:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542645320; bh=sGUH1TyEtOhx69kdLWfx+TJvxzRyoV34xtrpcnSOh/I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c8ksvzKgZw12NB2ouDH3WzmZ7CanKkR9nsGQ4rSl8Vp0RFrJD1qNwn+uZD7jFQxDD Q5WcoVR16WvLA7K+H3Sa9rCwM59JhTPDZW6wJUu+44HV5X3eIdXlPPfl6UbODghvoT 5JxYI3MnUNPpHDQBItPkNjOapoPihf2hnj9OfqyA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "H. Peter Anvin (Intel)" , "Cc: Johan Hovold" , Jiri Slaby , Al Viro , Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Gleixner , Kate Stewart , Philippe Ombredanne , Eugene Syromiatnikov , Alan Cox Subject: [PATCH 4.19 120/205] termios, tty/tty_baudrate.c: fix buffer overrun Date: Mon, 19 Nov 2018 17:27:07 +0100 Message-Id: <20181119162635.927742775@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181119162616.586062722@linuxfoundation.org> References: <20181119162616.586062722@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable 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 Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_baudrate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/tty/tty_baudrate.c +++ b/drivers/tty/tty_baudrate.c @@ -77,7 +77,7 @@ 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); @@ -113,7 +113,7 @@ 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 /* IBSHIFT */ return tty_termios_baud_rate(termios); #endif /* IBSHIFT */