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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 1015AC388F7 for ; Thu, 22 Oct 2020 11:33:57 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8373E206F7 for ; Thu, 22 Oct 2020 11:33:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="L1HYB4Gb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8373E206F7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=q/92rCEjz2yDwh4EVCMQacXoagx8SVTDstVGq+dbUgw=; b=L1HYB4GbuMxFwP+rCTwdouBG9 8KxURlm/9eFiFqZTVjp8NRAMmd9EikLy4DW2Vdgw40Xynd+Ud4/uUIARRSrBbR+7OQl8WEGCoxVLg rTUlh/982yaqmaj/eJ4ZzAl29r1BAZWomInQ33hw4iZIvSpjKsVAItJo0RliCKBDn2L9A9j5on8ig 6AmXnXKY7tPhGQB13GRK+w9pso+JA8xtcWuF7uRkjV6mhfUOJUjBb2aL9Y86MLs4Yx0mjzyJPHs68 3am2IGz3cc6xcEc+aafT/72koOFgJHbgSDO1aaDq/RFLqdlHWab8pSI1nB34mNLJ7WvXuhj+XF0M3 u1x4mVffQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kVYpP-0006G1-4t; Thu, 22 Oct 2020 11:32:19 +0000 Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kVYpL-0006Fc-Nt; Thu, 22 Oct 2020 11:32:15 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 26722302753; Thu, 22 Oct 2020 13:32:14 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 15E6B203D0810; Thu, 22 Oct 2020 13:32:14 +0200 (CEST) Date: Thu, 22 Oct 2020 13:32:14 +0200 From: Peter Zijlstra To: Sai Prakash Ranjan Subject: Re: [PATCHv2 2/4] coresight: tmc-etf: Fix NULL ptr dereference in tmc_enable_etf_sink_perf() Message-ID: <20201022113214.GD2611@hirez.programming.kicks-ass.net> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Mathieu Poirier , Suzuki K Poulose , Alexander Shishkin , linux-arm-msm@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Stephen Boyd , Ingo Molnar , Namhyung Kim , Jiri Olsa , linux-arm-kernel@lists.infradead.org, Mike Leach Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Oct 22, 2020 at 04:27:52PM +0530, Sai Prakash Ranjan wrote: > Looking at the ETR and other places in the kernel, ETF and the > ETB are the only places trying to dereference the task(owner) > in tmc_enable_etf_sink_perf() which is also called from the > sched_in path as in the call trace. > @@ -391,6 +392,10 @@ static void *tmc_alloc_etf_buffer(struct coresight_device *csdev, > { > int node; > struct cs_buffers *buf; > + struct task_struct *task = READ_ONCE(event->owner); > + > + if (!task || is_kernel_event(event)) > + return NULL; This is *wrong*... why do you care about who owns the events? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel