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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 670CCC04AA7 for ; Mon, 13 May 2019 12:41:37 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D8064206A3 for ; Mon, 13 May 2019 12:41:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D8064206A3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:56669 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQAGt-000638-Rj for qemu-devel@archiver.kernel.org; Mon, 13 May 2019 08:41:35 -0400 Received: from eggs.gnu.org ([209.51.188.92]:47003) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQAEv-0004nh-IL for qemu-devel@nongnu.org; Mon, 13 May 2019 08:39:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hQAEu-0004l4-Mf for qemu-devel@nongnu.org; Mon, 13 May 2019 08:39:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37984) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hQAEu-0004kw-HO for qemu-devel@nongnu.org; Mon, 13 May 2019 08:39:32 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DBA7C356F6 for ; Mon, 13 May 2019 12:39:31 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-28.ams2.redhat.com [10.36.116.28]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AEBB2600C8; Mon, 13 May 2019 12:39:28 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 2DC4111385E4; Mon, 13 May 2019 14:39:24 +0200 (CEST) From: Markus Armbruster To: Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= References: <20190418145355.21100-1-armbru@redhat.com> <20190418145355.21100-4-armbru@redhat.com> <78da03ed-2b9f-2357-6f28-44115d8b2955@redhat.com> Date: Mon, 13 May 2019 14:39:24 +0200 In-Reply-To: <78da03ed-2b9f-2357-6f28-44115d8b2955@redhat.com> ("Philippe =?utf-8?Q?Mathieu-Daud=C3=A9=22's?= message of "Thu, 18 Apr 2019 17:26:54 +0200") Message-ID: <87ef527clf.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Mon, 13 May 2019 12:39:31 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH 3/6] gdbstub: Reject invalid RLE repeat counts X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Philippe Mathieu-Daud=C3=A9 writes: > On 4/18/19 4:53 PM, Markus Armbruster wrote: >> "Debugging with GDB / Appendix E GDB Remote Serial Protocol / >> Overview" specifies "The printable characters '#' and '$' or with a >> numeric value greater than 126 must not be used." gdb_read_byte() >> only rejects values < 32. This is wrong. Impact depends on the caller: >>=20 >> * gdb_handlesig() passes a char. Incorrectly accepts '#', '$' and >> '\127'. >>=20 >> * gdb_chr_receive() passes an uint8_t. Additionally accepts >> characters with the most-significant bit set. >>=20 >> Correct the validity check to match the specification. >>=20 >> Signed-off-by: Markus Armbruster >> --- >> gdbstub.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >>=20 >> diff --git a/gdbstub.c b/gdbstub.c >> index d54abd17cc..a6dce1b027 100644 >> --- a/gdbstub.c >> +++ b/gdbstub.c >> @@ -2064,7 +2064,7 @@ static void gdb_read_byte(GDBState *s, int ch) >> } >> break; >> case RS_GETLINE_RLE: >> - if (ch < ' ') { > > Can you add a comment referring to the ""Debugging with GDB / Appendix E > GDB Remote Serial Protocol / Overview" here? Like this? case RS_GETLINE_RLE: /* * Run-length encoding is explained in "Debugging with GDB / * Appendix E GDB Remote Serial Protocol / Overview". */ if (ch < ' ') { > Reviewed-by: Philippe Mathieu-Daud=C3=A9 Thanks! >> + if (ch < ' ' || ch =3D=3D '#' || ch =3D=3D '$' || ch > 126)= { >> /* invalid RLE count encoding */ >> trace_gdbstub_err_invalid_repeat((uint8_t)ch); >> s->state =3D RS_GETLINE; >>=20