From patchwork Mon Oct 5 20:45:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11817719 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1C8C3139A for ; Mon, 5 Oct 2020 20:45:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFDDD212CC for ; Mon, 5 Oct 2020 20:45:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="AIKmxUEZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727338AbgJEUpW (ORCPT ); Mon, 5 Oct 2020 16:45:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725864AbgJEUpW (ORCPT ); Mon, 5 Oct 2020 16:45:22 -0400 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72A38C0613CE for ; Mon, 5 Oct 2020 13:45:22 -0700 (PDT) Received: by mail-pf1-x444.google.com with SMTP id a200so2887976pfa.10 for ; Mon, 05 Oct 2020 13:45:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=VMCvM/lVmSD+WoCXLV03EzHmNxDtsAkuJmb4ll+kKtw=; b=AIKmxUEZMVDxIcg4HDZZ+EWVJoorsD2ZAvAuSzmr2xiBCxBBInJKEqNLtgwRijVi1o NQDA1gGYhDFfByHmbEUT7KdTnwM+WC56xrdpnNaNeWxehBLmen+AolAiZtMbKSJKJDDL YCTrr8HUyH4yokR8Q6GoVT47D0p276zMrnMCY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=VMCvM/lVmSD+WoCXLV03EzHmNxDtsAkuJmb4ll+kKtw=; b=ZBySrz/W8IRLA3M+5PrZikokAMQS8E3C3AlhuJlPHbEEcoln4z/Vm7dSVCBcPdO4bV iMKN1+36omSDW75VITYW1HYwAXk3WKXHm6PdOak+xOnsWa+66IIHW6WHLACxYM/FQqov 07KZVafYhKdT73DMSrbU8xRu523Vkrdcyab4OMnOpfBFXWh9zcF5DU3dWUy6zIlm0yBA +25e+HQvZqMHQ+NppKDuN9erc8xrzwolTpguLMJre+sfwemxdjhF8SgSSpZR7SEKky8t E5Kh5gahmLsbe2iQlNjPwSY4K62JqjOa1iKi4FyK1N3ZliVkpTr/sPxcajAG7Yyu/YeF FuCg== X-Gm-Message-State: AOAM533a0dBrcLGc26TpEnZTYfAjp3NL3BcDbu95nvwtN2xAt+WAj0Dm 3QaodufzOQoiRrusT3hRUPOpDg== X-Google-Smtp-Source: ABdhPJxGnRw0v6Z5EdICY7GvvnOsRaK8GQdlmuTPfJGHKAxCOIZBLjUIdSH/e7cTEU/ZnbdVPz/c/w== X-Received: by 2002:aa7:9522:0:b029:142:2501:3986 with SMTP id c2-20020aa795220000b029014225013986mr1325575pfp.75.1601930721886; Mon, 05 Oct 2020 13:45:21 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id s4sm800489pfu.107.2020.10.05.13.45.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Oct 2020 13:45:21 -0700 (PDT) From: Kees Cook To: Shuah Khan Cc: Kees Cook , kernel test robot , Christoph Hellwig , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] selftests: splice: Adjust for handler fallback removal Date: Mon, 5 Oct 2020 13:45:17 -0700 Message-Id: <20201005204517.2652730-1-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Some pseudo-filesystems do not have an explicit splice fops since adding commit 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops"), and now will reject attempts to use splice() in those filesystem paths. Reported-by: kernel test robot Link: https://lore.kernel.org/lkml/202009181443.C2179FB@keescook/ Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Signed-off-by: Kees Cook --- .../selftests/splice/short_splice_read.sh | 119 ++++++++++++++---- 1 file changed, 98 insertions(+), 21 deletions(-) diff --git a/tools/testing/selftests/splice/short_splice_read.sh b/tools/testing/selftests/splice/short_splice_read.sh index 7810d3589d9a..22b6c8910b18 100755 --- a/tools/testing/selftests/splice/short_splice_read.sh +++ b/tools/testing/selftests/splice/short_splice_read.sh @@ -1,21 +1,87 @@ #!/bin/sh # SPDX-License-Identifier: GPL-2.0 +# +# Test for mishandling of splice() on pseudofilesystems, which should catch +# bugs like 11990a5bd7e5 ("module: Correctly truncate sysfs sections output") +# +# Since splice fallback was removed as part of the set_fs() rework, many of these +# tests expect to fail now. See https://lore.kernel.org/lkml/202009181443.C2179FB@keescook/ set -e +DIR=$(dirname "$0") + ret=0 +expect_success() +{ + title="$1" + shift + + echo "" >&2 + echo "$title ..." >&2 + + set +e + "$@" + rc=$? + set -e + + case "$rc" in + 0) + echo "ok: $title succeeded" >&2 + ;; + 1) + echo "FAIL: $title should work" >&2 + ret=$(( ret + 1 )) + ;; + *) + echo "FAIL: something else went wrong" >&2 + ret=$(( ret + 1 )) + ;; + esac +} + +expect_failure() +{ + title="$1" + shift + + echo "" >&2 + echo "$title ..." >&2 + + set +e + "$@" + rc=$? + set -e + + case "$rc" in + 0) + echo "FAIL: $title unexpectedly worked" >&2 + ret=$(( ret + 1 )) + ;; + 1) + echo "ok: $title correctly failed" >&2 + ;; + *) + echo "FAIL: something else went wrong" >&2 + ret=$(( ret + 1 )) + ;; + esac +} + do_splice() { filename="$1" bytes="$2" expected="$3" + report="$4" - out=$(./splice_read "$filename" "$bytes" | cat) + out=$("$DIR"/splice_read "$filename" "$bytes" | cat) if [ "$out" = "$expected" ] ; then - echo "ok: $filename $bytes" + echo " matched $report" >&2 + return 0 else - echo "FAIL: $filename $bytes" - ret=1 + echo " no match: '$out' vs $report" >&2 + return 1 fi } @@ -23,34 +89,45 @@ test_splice() { filename="$1" + echo " checking $filename ..." >&2 + full=$(cat "$filename") + rc=$? + if [ $rc -ne 0 ] ; then + return 2 + fi + two=$(echo "$full" | grep -m1 . | cut -c-2) # Make sure full splice has the same contents as a standard read. - do_splice "$filename" 4096 "$full" + echo " splicing 4096 bytes ..." >&2 + if ! do_splice "$filename" 4096 "$full" "full read" ; then + return 1 + fi # Make sure a partial splice see the first two characters. - do_splice "$filename" 2 "$two" + echo " splicing 2 bytes ..." >&2 + if ! do_splice "$filename" 2 "$two" "'$two'" ; then + return 1 + fi + + return 0 } -# proc_single_open(), seq_read() -test_splice /proc/$$/limits -# special open, seq_read() -test_splice /proc/$$/comm +### /proc/$pid/ has no splice interface; these should all fail. +expect_failure "proc_single_open(), seq_read() splice" test_splice /proc/$$/limits +expect_failure "special open(), seq_read() splice" test_splice /proc/$$/comm -# proc_handler, proc_dointvec_minmax -test_splice /proc/sys/fs/nr_open -# proc_handler, proc_dostring -test_splice /proc/sys/kernel/modprobe -# proc_handler, special read -test_splice /proc/sys/kernel/version +### /proc/sys/ has a splice interface; these should all succeed. +expect_success "proc_handler: proc_dointvec_minmax() splice" test_splice /proc/sys/fs/nr_open +expect_success "proc_handler: proc_dostring() splice" test_splice /proc/sys/kernel/modprobe +expect_success "proc_handler: special read splice" test_splice /proc/sys/kernel/version +### /sys/ has no splice interface; these should all fail. if ! [ -d /sys/module/test_module/sections ] ; then - modprobe test_module + expect_success "test_module kernel module load" modprobe test_module fi -# kernfs, attr -test_splice /sys/module/test_module/coresize -# kernfs, binattr -test_splice /sys/module/test_module/sections/.init.text +expect_failure "kernfs attr splice" test_splice /sys/module/test_module/coresize +expect_failure "kernfs binattr splice" test_splice /sys/module/test_module/sections/.init.text exit $ret