From patchwork Mon Jun 14 10:27:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 459808 Delivered-To: patch@linaro.org Received: by 2002:a02:735a:0:0:0:0:0 with SMTP id a26csp3162259jae; Mon, 14 Jun 2021 03:45:57 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwj0i/kmnhmgCArR7/GOJEWuSZmQDmGUszUWJ6dq6GHz9TbQVk2c1zABQYug9lEGHaQxHiZ X-Received: by 2002:a05:6402:8d4:: with SMTP id d20mr16092662edz.117.1623667557202; Mon, 14 Jun 2021 03:45:57 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1623667557; cv=none; d=google.com; s=arc-20160816; b=t/ceG7U3E5QVdEkdj/AFk4EMpuL3omP+NfyTq84980Wp2kKdJpr5poyGcta95Tm6pm OlstONwd9ktaDG+qbLtad0uFWn2UNvBJ/iSKiHxJutDYCR0ifpsiIMZaWfy0HcfMHdIq daZ5BFjeX8wef4ML7oGHGysEMPYVETZP66WfcROLKKKv1v76HF3aZ8lJ54eZgXEevAV9 nR0WM+X3NcmgcADo7BqyUj9BH3GsZletpuLI8Ya+7dnsh/rYif+PUeHbW8cXBaL9mamb H78IFWgu7j66hhHoXaJu6J3xksoaf8o4Sq1R1PO60prXApGK89t+EVwC5JKpj5SiHQWA q6wA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=02G9aVApv1HZrPfRIN01HQFLjtBPAJ4guhnhScTHi18=; b=CegefLjT3z1i5UWEZmJ8JwBTVG6LBEgnH677n0o2YXJJ5utYBj5ATiNQseTcvgNiKM aeRIzFGYDSS/RFw3cBd284ItsiSvqK8Haad6tWbu3jvHa5AgfyDUpgW535i56AakoeoA pmIbLVHiZ1hEZ7j/TeAQUTgjIAf0AKyVJFOPGkJMZym7IS/1a11OlF1HOq5xqFBpDXaX Wl4K/CRXz8fvyQ2Cr4iCulTPCyWQaHAmYPRiyyPy3yLpDbXd8VzV8ITPfx3RwgrrB9Q+ QOMWoXcpBFgOFbtr+Ds739C4tbrOWod1MiiBui7tmd0zBYBcPh2hhGzXWPyHpAsbDcfb n+bg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=GCEsJG5i; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id f3si3497708ejl.241.2021.06.14.03.45.57; Mon, 14 Jun 2021 03:45:57 -0700 (PDT) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=GCEsJG5i; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233042AbhFNKr6 (ORCPT + 12 others); Mon, 14 Jun 2021 06:47:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:50316 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232796AbhFNKp4 (ORCPT ); Mon, 14 Jun 2021 06:45:56 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 82ABA613D3; Mon, 14 Jun 2021 10:36:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623666999; bh=Zrnh7qmLrObb24IuG3WZ+Fx9/p+T9L6ChHDry08hZrs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GCEsJG5iunNh4CYmyP3YY174pJx1j7rW/y8MkRb4b31h5tyQsuNnplSydziZc7JqH qMuJLp4OtzFzs2lpt59zwT0BtBrhaAfmS/H2NX2ZoJZmUmzi2m6L49zqMvjbtSHzBN ximeFta3A7yGLtPEo5igdSliBCNZ2VLaBU2fgpJs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Leo Yan , Adrian Hunter , Jiri Olsa , Alexander Shishkin , Kan Liang , Mark Rutland , Namhyung Kim , Peter Zijlstra , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 4.19 58/67] perf session: Correct buffer copying when peeking events Date: Mon, 14 Jun 2021 12:27:41 +0200 Message-Id: <20210614102645.729398944@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210614102643.797691914@linuxfoundation.org> References: <20210614102643.797691914@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Leo Yan [ Upstream commit 197eecb6ecae0b04bd694432f640ff75597fed9c ] When peeking an event, it has a short path and a long path. The short path uses the session pointer "one_mmap_addr" to directly fetch the event; and the long path needs to read out the event header and the following event data from file and fill into the buffer pointer passed through the argument "buf". The issue is in the long path that it copies the event header and event data into the same destination address which pointer "buf", this means the event header is overwritten. We are just lucky to run into the short path in most cases, so we don't hit the issue in the long path. This patch adds the offset "hdr_sz" to the pointer "buf" when copying the event data, so that it can reserve the event header which can be used properly by its caller. Fixes: 5a52f33adf02 ("perf session: Add perf_session__peek_event()") Signed-off-by: Leo Yan Acked-by: Adrian Hunter Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20210605052957.1070720-1-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/session.c | 1 + 1 file changed, 1 insertion(+) -- 2.30.2 diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 6a2037b52098..3be1534f1f03 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -1478,6 +1478,7 @@ int perf_session__peek_event(struct perf_session *session, off_t file_offset, if (event->header.size < hdr_sz || event->header.size > buf_sz) return -1; + buf += hdr_sz; rest = event->header.size - hdr_sz; if (readn(fd, buf, rest) != (ssize_t)rest)