From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gproxy2-pub.mail.unifiedlayer.com (gproxy2-pub.mail.unifiedlayer.com [69.89.18.3]) by sourceware.org (Postfix) with ESMTPS id B4A5A38485B8 for ; Thu, 28 Apr 2022 15:26:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B4A5A38485B8 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=tromey.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tromey.com Received: from cmgw12.mail.unifiedlayer.com (unknown [10.0.90.127]) by progateway4.mail.pro1.eigbox.com (Postfix) with ESMTP id 0722D10042942 for ; Thu, 28 Apr 2022 15:26:28 +0000 (UTC) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with ESMTP id k62Fnh1xcb2WGk62FnygaK; Thu, 28 Apr 2022 15:26:28 +0000 X-Authority-Reason: nr=8 X-Authority-Analysis: v=2.4 cv=SqtVVNC0 c=1 sm=1 tr=0 ts=626ab224 a=ApxJNpeYhEAb1aAlGBBbmA==:117 a=ApxJNpeYhEAb1aAlGBBbmA==:17 a=dLZJa+xiwSxG16/P+YVxDGlgEgI=:19 a=z0gMJWrwH1QA:10:nop_rcvd_month_year a=Qbun_eYptAEA:10:endurance_base64_authed_username_1 a=CCpqsmhAAAAA:8 a=67JURp0W6y8sqRM1aYAA:9 a=ul9cdbp4aOFLsgKbc677:22 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tromey.com; s=default; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date:References :Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=qRk/irK05ZobSTL6rfaRjihATJarILRiLrg6jZO3uRc=; b=KxN+QoswhiA8HuSbyiYpLCQ1Nk KfLZhlXarxZ9P0HUp//G7eUWnus6OlhKVjfQeBdu95xqbykJZzzZ3exP+frnCOz31TUYZD8SdRt9G hB4/I+J/YzUSXfc7HpoKPyAEH; Received: from 71-211-158-194.hlrn.qwest.net ([71.211.158.194]:55688 helo=murgatroyd) by box5379.bluehost.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nk62F-001cna-5R; Thu, 28 Apr 2022 09:26:27 -0600 From: Tom Tromey To: Luis Machado via Gdb-patches Subject: Re: [PATCH] Fix crash with "maintenance print arc" References: <20220427100753.364631-1-luis.machado@arm.com> X-Attribution: Tom Date: Thu, 28 Apr 2022 09:26:26 -0600 In-Reply-To: <20220427100753.364631-1-luis.machado@arm.com> (Luis Machado via Gdb-patches's message of "Wed, 27 Apr 2022 11:07:53 +0100") Message-ID: <87h76dmdp9.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - box5379.bluehost.com X-AntiAbuse: Original Domain - sourceware.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - tromey.com X-BWhitelist: no X-Source-IP: 71.211.158.194 X-Source-L: No X-Exim-ID: 1nk62F-001cna-5R X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 71-211-158-194.hlrn.qwest.net (murgatroyd) [71.211.158.194]:55688 X-Source-Auth: tom+tromey.com X-Email-Count: 1 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-Spam-Status: No, score=-3029.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, GIT_PATCH_0, JMQ_SPF_NEUTRAL, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Apr 2022 15:26:30 -0000 >>>>> "Luis" == Luis Machado via Gdb-patches writes: Luis> While doing something else, I noticed GDB crashed with Luis> "maintenance print arc". I think the bug here is that this uses add_show_prefix_cmd and not add_basic_prefix_cmd. See the appended, which also fixes the crash. Luis> This happens because the code expects to find a "show" string pattern Luis> within "maintenance print arc", since "arc" here is a prefix, and skip it. Luis> In this case though, it won't find it, and we will have a bad pointer Luis> getting dereferenced. This looks reasonable to me. Tom diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c index 98bd1c4bc0a..3edfd466f3b 100644 --- a/gdb/arc-tdep.c +++ b/gdb/arc-tdep.c @@ -2474,11 +2474,11 @@ _initialize_arc_tdep () /* Register ARC-specific commands with gdb. */ /* Add root prefix command for "maintenance print arc" commands. */ - add_show_prefix_cmd ("arc", class_maintenance, - _("ARC-specific maintenance commands for printing GDB " - "internal state."), - &maintenance_print_arc_list, - 0, &maintenanceprintlist); + add_basic_prefix_cmd ("arc", class_maintenance, + _("ARC-specific maintenance commands for printing GDB " + "internal state."), + &maintenance_print_arc_list, + 0, &maintenanceprintlist); add_cmd ("arc-instruction", class_maintenance, dump_arc_instruction_command,