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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 68F19C5DF60 for ; Thu, 7 Nov 2019 19:08:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37CC12085B for ; Thu, 7 Nov 2019 19:08:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573153737; bh=qOVNBNhh+a7Rh0A9ImEWgTHVRvvCQKJDJeLxlDGcj5U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WN3WhDaOTy+JQRUmhthIZkjRepPPwO9/u0IUZ1hZlTcTBeNL4QVJF2mMFt+H3doBd K+CKUp1SJ44lf14lR/O8UjNDPeXYgnJtiqYMH+iOd8LhBH90JNQcmIC48xGw7aKZR8 7bA3khk0Nzy6U3uBdjuFRn0wM0PyCyZtCashec8s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731212AbfKGTIz (ORCPT ); Thu, 7 Nov 2019 14:08:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:47412 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728655AbfKGTIy (ORCPT ); Thu, 7 Nov 2019 14:08:54 -0500 Received: from quaco.ghostprotocols.net (179-240-172-58.3g.claro.net.br [179.240.172.58]) (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 BAA9621882; Thu, 7 Nov 2019 19:08:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573153733; bh=qOVNBNhh+a7Rh0A9ImEWgTHVRvvCQKJDJeLxlDGcj5U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=noqcsVhmHUEcg6KmS15K0jAVEHZM2HDY06gaHsR1+buYpNM8Ox2o/T6gmCIZSvZpG 5U8ZfuEQH9gHP3cIAH2e5btgdSBKy4f9JYY07vXRWOWp7ls9hTu4Phya75pUHdwwud wzgtxD2QtwvV20aOaHU8GLl49NBb6BTcSJ/V8uVk= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Leo Yan , Alexander Shishkin , Mark Rutland , Naresh Kamboju , Peter Zijlstra , Wang Nan , stable@vger.kernel.org, Arnaldo Carvalho de Melo Subject: [PATCH 56/63] perf tests: Fix out of bounds memory access Date: Thu, 7 Nov 2019 16:00:04 -0300 Message-Id: <20191107190011.23924-57-acme@kernel.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191107190011.23924-1-acme@kernel.org> References: <20191107190011.23924-1-acme@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Leo Yan The test case 'Read backward ring buffer' failed on 32-bit architectures which were found by LKFT perf testing. The test failed on arm32 x15 device, qemu_arm32, qemu_i386, and found intermittent failure on i386; the failure log is as below: 50: Read backward ring buffer : --- start --- test child forked, pid 510 Using CPUID GenuineIntel-6-9E-9 mmap size 1052672B mmap size 8192B Finished reading overwrite ring buffer: rewind free(): invalid next size (fast) test child interrupted ---- end ---- Read backward ring buffer: FAILED! The log hints there have issue for memory usage, thus free() reports error 'invalid next size' and directly exit for the case. Finally, this issue is root caused as out of bounds memory access for the data array 'evsel->id'. The backward ring buffer test invokes do_test() twice. 'evsel->id' is allocated at the first call with the flow: test__backward_ring_buffer() `-> do_test() `-> evlist__mmap() `-> evlist__mmap_ex() `-> perf_evsel__alloc_id() So 'evsel->id' is allocated with one item, and it will be used in function perf_evlist__id_add(): evsel->id[0] = id evsel->ids = 1 At the second call for do_test(), it skips to initialize 'evsel->id' and reuses the array which is allocated in the first call. But 'evsel->ids' contains the stale value. Thus: evsel->id[1] = id -> out of bound access evsel->ids = 2 To fix this issue, we will use evlist__open() and evlist__close() pair functions to prepare and cleanup context for evlist; so 'evsel->id' and 'evsel->ids' can be initialized properly when invoke do_test() and avoid the out of bounds memory access. Fixes: ee74701ed8ad ("perf tests: Add test to check backward ring buffer") Signed-off-by: Leo Yan Reviewed-by: Jiri Olsa Cc: Alexander Shishkin Cc: Mark Rutland Cc: Namhyung Kim Cc: Naresh Kamboju Cc: Peter Zijlstra Cc: Wang Nan Cc: stable@vger.kernel.org # v4.10+ Link: http://lore.kernel.org/lkml/20191107020244.2427-1-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/tests/backward-ring-buffer.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c index a4cd30c0beb3..15cea518f5ad 100644 --- a/tools/perf/tests/backward-ring-buffer.c +++ b/tools/perf/tests/backward-ring-buffer.c @@ -148,6 +148,15 @@ int test__backward_ring_buffer(struct test *test __maybe_unused, int subtest __m goto out_delete_evlist; } + evlist__close(evlist); + + err = evlist__open(evlist); + if (err < 0) { + pr_debug("perf_evlist__open: %s\n", + str_error_r(errno, sbuf, sizeof(sbuf))); + goto out_delete_evlist; + } + err = do_test(evlist, 1, &sample_count, &comm_count); if (err != TEST_OK) goto out_delete_evlist; -- 2.21.0