From patchwork Thu Oct 18 06:59:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 10646781 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 98F00109C for ; Thu, 18 Oct 2018 06:59:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8BA64287BB for ; Thu, 18 Oct 2018 06:59:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7FC7E287F4; Thu, 18 Oct 2018 06:59:27 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2028E287BB for ; Thu, 18 Oct 2018 06:59:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727597AbeJRO6z (ORCPT ); Thu, 18 Oct 2018 10:58:55 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:40482 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727363AbeJRO6x (ORCPT ); Thu, 18 Oct 2018 10:58:53 -0400 Received: by mail-pg1-f194.google.com with SMTP id n31-v6so13740986pgm.7 for ; Wed, 17 Oct 2018 23:59:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=/VyGfWQacueEUHTGPoQ3uFdYU/4GyGaHaoBL4dBXqp8=; b=DfksOTMPnGLSt+/RZVbtrmZH+aUqtKZ9anz+d0UFot8eCfcdCf686Kgfs2EwSZu5tI /paN5Ys1hMjJp+YCZH1bFHtPB2OgWbeFXPV3FmFTN9aWRdsDYc5RgLoKzciA+gXwfIw/ JIgYuws1P9Eb1SydvkYErc+X99w9lMAz/+IyQ= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=/VyGfWQacueEUHTGPoQ3uFdYU/4GyGaHaoBL4dBXqp8=; b=I0KOI7d/2qN1Per2yKqYVS1zC/d6XRSYl0Li86sOmGolikZmw9aBHCxAiH4QQ7cr/R NjdnH+qKgHKk5ngQ7sefepUHMH8wfiHhJxRqi7JyC0soJ21MkS9tJbRVTxmwnBWrerkW XrjuNyT7Rynkd2wHjX8IyY2oIs2u/7DCJrEe8jTxMstv8Xf7grVcpd6pGwi61ilUOCl0 EEy1/K/2xEu0EfCspoNo9cjYYp11swqGtC4DtdkdM3W1wlrPPG1qzhIIFb/WcTMqHxyY VHr6d/S/n9vTaSfwkkv037PnvzsHnsjoj/UcX6ocm+wHZ5/0T4uhZ20+nNYF1fMm4HwR yvFA== X-Gm-Message-State: ABuFfog6cSQf3N7+lyaXnRILW35VLxJW3m57MF0iWhJ+tsi9sTb3vBK+ oHsx88ChD2y9hNKuBBwrXrAdAw== X-Google-Smtp-Source: ACcGV61MVMwfFrq1iY6mCNrXqt8vwRjugldQxLhW5AVm7ZVRL/BogArhefTux89TWrApAiEACQS/Uw== X-Received: by 2002:a63:7044:: with SMTP id a4-v6mr27475186pgn.63.1539845959538; Wed, 17 Oct 2018 23:59:19 -0700 (PDT) Received: from joelaf.mtv.corp.google.com ([2620:0:1000:1601:3aef:314f:b9ea:889f]) by smtp.gmail.com with ESMTPSA id r23-v6sm21580750pfh.79.2018.10.17.23.59.17 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 17 Oct 2018 23:59:18 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, "Joel Fernandes (Google)" , dancol@google.com, minchan@kernel.org, Al Viro , Andrew Morton , gregkh@linuxfoundation.org, "J. Bruce Fields" , Jeff Layton , John Stultz , jreck@google.com, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, marcandre.lureau@redhat.com, Mike Kravetz , Shuah Khan , Thomas Gleixner , tkjos@google.com Subject: [PATCH v3 2/2] selftests/memfd: Add tests for F_SEAL_FS_WRITE seal Date: Wed, 17 Oct 2018 23:59:08 -0700 Message-Id: <20181018065908.254389-2-joel@joelfernandes.org> X-Mailer: git-send-email 2.19.1.331.ge82ca0e54c-goog In-Reply-To: <20181018065908.254389-1-joel@joelfernandes.org> References: <20181018065908.254389-1-joel@joelfernandes.org> MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add tests to verify sealing memfds with the F_SEAL_FS_WRITE works as expected. Cc: dancol@google.com Cc: minchan@kernel.org Reviewed-by: John Stultz Signed-off-by: Joel Fernandes (Google) --- tools/testing/selftests/memfd/memfd_test.c | 74 ++++++++++++++++++++++ 1 file changed, 74 insertions(+) diff --git a/tools/testing/selftests/memfd/memfd_test.c b/tools/testing/selftests/memfd/memfd_test.c index 10baa1652fc2..32b207ca7372 100644 --- a/tools/testing/selftests/memfd/memfd_test.c +++ b/tools/testing/selftests/memfd/memfd_test.c @@ -692,6 +692,79 @@ static void test_seal_write(void) close(fd); } +/* + * Test SEAL_FUTURE_WRITE + * Test whether SEAL_FUTURE_WRITE actually prevents modifications. + */ +static void test_seal_future_write(void) +{ + int fd; + void *p; + + printf("%s SEAL-FUTURE-WRITE\n", memfd_str); + + fd = mfd_assert_new("kern_memfd_seal_future_write", + mfd_def_size, + MFD_CLOEXEC | MFD_ALLOW_SEALING); + + p = mfd_assert_mmap_shared(fd); + + mfd_assert_has_seals(fd, 0); + /* Not adding grow/shrink seals makes the future write + * seal fail to get added + */ + mfd_fail_add_seals(fd, F_SEAL_FUTURE_WRITE); + + mfd_assert_add_seals(fd, F_SEAL_GROW); + mfd_assert_has_seals(fd, F_SEAL_GROW); + + /* Should still fail since shrink seal has + * not yet been added + */ + mfd_fail_add_seals(fd, F_SEAL_FUTURE_WRITE); + + mfd_assert_add_seals(fd, F_SEAL_SHRINK); + mfd_assert_has_seals(fd, F_SEAL_GROW | + F_SEAL_SHRINK); + + /* Now should succeed, also verifies that the seal + * could be added with an existing writable mmap + */ + mfd_assert_add_seals(fd, F_SEAL_FUTURE_WRITE); + mfd_assert_has_seals(fd, F_SEAL_SHRINK | + F_SEAL_GROW | + F_SEAL_FUTURE_WRITE); + + /* read should pass, writes should fail */ + mfd_assert_read(fd); + mfd_fail_write(fd); + + munmap(p, mfd_def_size); + close(fd); + + /* Test adding all seals (grow, shrink, future write) at once */ + fd = mfd_assert_new("kern_memfd_seal_future_write2", + mfd_def_size, + MFD_CLOEXEC | MFD_ALLOW_SEALING); + + p = mfd_assert_mmap_shared(fd); + + mfd_assert_has_seals(fd, 0); + mfd_assert_add_seals(fd, F_SEAL_SHRINK | + F_SEAL_GROW | + F_SEAL_FUTURE_WRITE); + mfd_assert_has_seals(fd, F_SEAL_SHRINK | + F_SEAL_GROW | + F_SEAL_FUTURE_WRITE); + + /* read should pass, writes should fail */ + mfd_assert_read(fd); + mfd_fail_write(fd); + + munmap(p, mfd_def_size); + close(fd); +} + /* * Test SEAL_SHRINK * Test whether SEAL_SHRINK actually prevents shrinking @@ -945,6 +1018,7 @@ int main(int argc, char **argv) test_basic(); test_seal_write(); + test_seal_future_write(); test_seal_shrink(); test_seal_grow(); test_seal_resize();