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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,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 87947C31E5B for ; Tue, 18 Jun 2019 16:18:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5C3DB213F2 for ; Tue, 18 Jun 2019 16:18:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560874728; bh=8IT6mIl1+85XfJ48HhaLGTHawDDCTjPYWxwxwjPe+zU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=G4gsgsX0t+KHzX2dRDwM6KoHtU6zLDSvrwCAJN8MwUYeNz4kFULZj5uCSCTowGKUb 9vTNukETGW3Pzqu2K/rqS+HPdEDmNIM7dwM6oboXudouJKSL2OKnkRWTNsfxZlUlXt pLkTbwpV2mtuj3DMMj3zPz4U4+PwvIGaPL0y9J/o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729851AbfFRQSq (ORCPT ); Tue, 18 Jun 2019 12:18:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:54236 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729320AbfFRQSq (ORCPT ); Tue, 18 Jun 2019 12:18:46 -0400 Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (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 A3E8E20B1F; Tue, 18 Jun 2019 16:18:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560874725; bh=8IT6mIl1+85XfJ48HhaLGTHawDDCTjPYWxwxwjPe+zU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=sWJEFZz9ZFAS+uZls7FFlRMq/x5Rdp1sbr7PlfyPXlcN7024WuynlYUS8/pIBDGe4 x5uHzpJzncvS9jqXz0NYAHnsnchqCJFNOnvRCrkHKieLw6drMrowwhgiICkEfkpt0B PmFY4OGpcRUMSZl2Im/E+3Ax+SGAFNlx/nCHgKLw= Date: Wed, 19 Jun 2019 01:18:41 +0900 From: Masami Hiramatsu To: Steven Rostedt Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Tom Zanussi , Ravi Bangoria , Namhyung Kim , Arnaldo Carvalho de Melo Subject: Re: [PATCH 16/21] tracing/uprobe: Add per-probe delete from event Message-Id: <20190619011841.99e204671417bd66a8d604fc@kernel.org> In-Reply-To: <20190617221646.7c848beb@oasis.local.home> References: <155931578555.28323.16360245959211149678.stgit@devnote2> <155931595698.28323.17594202275209962525.stgit@devnote2> <20190617221646.7c848beb@oasis.local.home> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 17 Jun 2019 22:16:46 -0400 Steven Rostedt wrote: > On Sat, 1 Jun 2019 00:19:17 +0900 > Masami Hiramatsu wrote: > > > +static bool trace_uprobe_match_command_head(struct trace_uprobe *tu, > > + int argc, const char **argv) > > +{ > > + char buf[MAX_ARGSTR_LEN + 1]; > > + int len; > > + > > + if (!argc) > > + return true; > > + > > + len = strlen(tu->filename); > > + if (argv[0][len] != ':' || strncmp(tu->filename, argv[0], len)) > > Hmm, isn't it possible that 'len' can be greater than whatever argv[0] is? > > The argv[0][len] looks very dangerous to me. Ah, right! it can lead an unexpected memory access! > > Perhaps that should be changed to: > > if (!(!strncmp(tu->filename, argv[0], len) && argv[0][len] == ':')) > > That way, the test of argv[0][len] will only happen if argv[0] is of length len. OK, I'll take it! Thank you! > > -- Steve > > > > + return false; > > + > > + if (tu->ref_ctr_offset == 0) > > + snprintf(buf, sizeof(buf), "0x%0*lx", > > + (int)(sizeof(void *) * 2), tu->offset); > > + else > > + snprintf(buf, sizeof(buf), "0x%0*lx(0x%lx)", > > + (int)(sizeof(void *) * 2), tu->offset, > > + tu->ref_ctr_offset); > > + if (strcmp(buf, &argv[0][len + 1])) > > + return false; > > + > > + argc--; argv++; > > + > > + return trace_probe_match_command_args(&tu->tp, argc, argv); > > +} > > + -- Masami Hiramatsu