From patchwork Tue Apr 26 08:20:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 566620 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E1DBC4332F for ; Tue, 26 Apr 2022 08:44:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239183AbiDZIr3 (ORCPT ); Tue, 26 Apr 2022 04:47:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346885AbiDZIp2 (ORCPT ); Tue, 26 Apr 2022 04:45:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89FE864C4; Tue, 26 Apr 2022 01:36:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 268D36185C; Tue, 26 Apr 2022 08:36:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 31A29C385AC; Tue, 26 Apr 2022 08:36:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1650962171; bh=v3d3wJ8d7he5GKQ/gI1Bji2FZeuuYgCu3YXM/O7M85o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iZpMRm+XASXQLK8kknecqQh5UBTZv9hmoacSUtjMoDJ5Uy7vuCY6c29Lflsq+Uq5+ ORO/XkoHGXODm93GQLtcuS7hIXUSFItd59X4yIOm2Ae2Us1ySIxNFkNJrON+OTXMhY L6J3w/RixkjbOwl2pp4g5dqKw0//668cdF8S8Pgk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Adrian Hunter , Ian Rogers , Jiri Olsa , Arnaldo Carvalho de Melo Subject: [PATCH 5.15 010/124] perf tools: Fix segfault accessing sample_id xyarray Date: Tue, 26 Apr 2022 10:20:11 +0200 Message-Id: <20220426081747.590453260@linuxfoundation.org> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220426081747.286685339@linuxfoundation.org> References: <20220426081747.286685339@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Adrian Hunter commit a668cc07f990d2ed19424d5c1a529521a9d1cee1 upstream. perf_evsel::sample_id is an xyarray which can cause a segfault when accessed beyond its size. e.g. # perf record -e intel_pt// -C 1 sleep 1 Segmentation fault (core dumped) # That is happening because a dummy event is opened to capture text poke events accross all CPUs, however the mmap logic is allocating according to the number of user_requested_cpus. In general, perf sometimes uses the evsel cpus to open events, and sometimes the evlist user_requested_cpus. However, it is not necessary to determine which case is which because the opened event file descriptors are also in an xyarray, the size of whch can be used to correctly allocate the size of the sample_id xyarray, because there is one ID per file descriptor. Note, in the affected code path, perf_evsel fd array is subsequently used to get the file descriptor for the mmap, so it makes sense for the xyarrays to be the same size there. Fixes: d1a177595b3a824c ("libperf: Adopt perf_evlist__mmap()/munmap() from tools/perf") Fixes: 246eba8e9041c477 ("perf tools: Add support for PERF_RECORD_TEXT_POKE") Signed-off-by: Adrian Hunter Acked-by: Ian Rogers Cc: Adrian Hunter Cc: Jiri Olsa Cc: stable@vger.kernel.org # 5.5+ Link: https://lore.kernel.org/r/20220413114232.26914-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/lib/perf/evlist.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/tools/lib/perf/evlist.c +++ b/tools/lib/perf/evlist.c @@ -577,7 +577,6 @@ int perf_evlist__mmap_ops(struct perf_ev { struct perf_evsel *evsel; const struct perf_cpu_map *cpus = evlist->cpus; - const struct perf_thread_map *threads = evlist->threads; if (!ops || !ops->get || !ops->mmap) return -EINVAL; @@ -589,7 +588,7 @@ int perf_evlist__mmap_ops(struct perf_ev perf_evlist__for_each_entry(evlist, evsel) { if ((evsel->attr.read_format & PERF_FORMAT_ID) && evsel->sample_id == NULL && - perf_evsel__alloc_id(evsel, perf_cpu_map__nr(cpus), threads->nr) < 0) + perf_evsel__alloc_id(evsel, evsel->fd->max_x, evsel->fd->max_y) < 0) return -ENOMEM; }