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=-11.0 required=3.0 tests=BAYES_00, BODY_QUOTE_MALF_MSGID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS 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 30F86C433E2 for ; Mon, 20 Jul 2020 12:58:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1214422B4D for ; Mon, 20 Jul 2020 12:58:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728822AbgGTM6q (ORCPT ); Mon, 20 Jul 2020 08:58:46 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:37484 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728074AbgGTM6q (ORCPT ); Mon, 20 Jul 2020 08:58:46 -0400 Received: from ip5f5af08c.dynamic.kabel-deutschland.de ([95.90.240.140] helo=wittgenstein) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jxVNB-0001cD-9Y; Mon, 20 Jul 2020 12:58:25 +0000 Date: Mon, 20 Jul 2020 14:58:23 +0200 From: Christian Brauner To: Adrian Reber Cc: Nicolas Viennot , Eric Biederman , Pavel Emelyanov , Oleg Nesterov , Dmitry Safonov <0x7f454c46@gmail.com>, Andrei Vagin , =?utf-8?B?TWljaGHFgiBDxYJhcGnFhHNraQ==?= , Kamil Yurtsever , Dirk Petersen , Christine Flood , Casey Schaufler , Mike Rapoport , Radostin Stoyanov , Cyrill Gorcunov , Serge Hallyn , Stephen Smalley , Sargun Dhillon , Arnd Bergmann , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, selinux@vger.kernel.org, Eric Paris , Jann Horn , linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v6 0/7] capabilities: Introduce CAP_CHECKPOINT_RESTORE Message-ID: <20200720125823.lp5anbgbm4hqlp74@wittgenstein> References: <20200719100418.2112740-1-areber@redhat.com> <20200719181729.6f37lilhvov5a74f@wittgenstein> <20200720115452.ne2vqtdneuungb3j@wittgenstein> <20200720124637.GA1788746@dcbz.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200720124637.GA1788746@dcbz.redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Mon, Jul 20, 2020 at 02:46:37PM +0200, Adrian Reber wrote: > On Mon, Jul 20, 2020 at 01:54:52PM +0200, Christian Brauner wrote: > > On Sun, Jul 19, 2020 at 08:17:30PM +0200, Christian Brauner wrote: > > > On Sun, Jul 19, 2020 at 12:04:10PM +0200, Adrian Reber wrote: > > > > This is v6 of the 'Introduce CAP_CHECKPOINT_RESTORE' patchset. The > > > > changes to v5 are: > > > > > > > > * split patch dealing with /proc/self/exe into two patches: > > > > * first patch to enable changing it with CAP_CHECKPOINT_RESTORE > > > > and detailed history in the commit message > > > > * second patch changes -EINVAL to -EPERM > > > > * use kselftest_harness.h infrastructure for test > > > > * replace if (!capable(CAP_SYS_ADMIN) || !capable(CAP_CHECKPOINT_RESTORE)) > > > > with if (!checkpoint_restore_ns_capable(&init_user_ns)) > > > > > > > > Adrian Reber (5): > > > > capabilities: Introduce CAP_CHECKPOINT_RESTORE > > > > pid: use checkpoint_restore_ns_capable() for set_tid > > > > pid_namespace: use checkpoint_restore_ns_capable() for ns_last_pid > > > > proc: allow access in init userns for map_files with > > > > CAP_CHECKPOINT_RESTORE > > > > selftests: add clone3() CAP_CHECKPOINT_RESTORE test > > > > > > > > Nicolas Viennot (2): > > > > prctl: Allow local CAP_CHECKPOINT_RESTORE to change /proc/self/exe > > > > prctl: exe link permission error changed from -EINVAL to -EPERM > > > > > > > > fs/proc/base.c | 8 +- > > > > include/linux/capability.h | 6 + > > > > include/uapi/linux/capability.h | 9 +- > > > > kernel/pid.c | 2 +- > > > > kernel/pid_namespace.c | 2 +- > > > > kernel/sys.c | 13 +- > > > > security/selinux/include/classmap.h | 5 +- > > > > tools/testing/selftests/clone3/.gitignore | 1 + > > > > tools/testing/selftests/clone3/Makefile | 4 +- > > > > .../clone3/clone3_cap_checkpoint_restore.c | 177 ++++++++++++++++++ > > > > 10 files changed, 212 insertions(+), 15 deletions(-) > > > > create mode 100644 tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c > > > > > > > > base-commit: d31958b30ea3b7b6e522d6bf449427748ad45822 > > > > > > Adrian, Nicolas thank you! > > > I grabbed the series to run the various core test-suites we've added > > > over the last year and pushed it to > > > https://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux.git/log/?h=cap_checkpoint_restore > > > for now to let kbuild/ltp chew on it for a bit. > > > > Ok, I ran the test-suite this morning and there's nothing to worry about > > it all passes _but_ the selftests had a bug using SKIP() instead of > > XFAIL() and they mixed ksft_print_msg() and TH_LOG(). I know that I > > think I mentioned to you that you can't use TH_LOG() outside of TEST*(). > > Turns out I was wrong. You can do it if you pass in a specific global > > variable. Here's the diff I applied on top of the selftests you sent. > > After these changes the output looks like this: > > > > [==========] Running 1 tests from 1 test cases. > > [ RUN ] global.clone3_cap_checkpoint_restore > > # clone3() syscall supported > > clone3_cap_checkpoint_restore.c:155:clone3_cap_checkpoint_restore:Child has PID 12303 > > clone3_cap_checkpoint_restore.c:88:clone3_cap_checkpoint_restore:[12302] Trying clone3() with CLONE_SET_TID to 12303 > > clone3_cap_checkpoint_restore.c:55:clone3_cap_checkpoint_restore:Operation not permitted - Failed to create new process > > clone3_cap_checkpoint_restore.c:90:clone3_cap_checkpoint_restore:[12302] clone3() with CLONE_SET_TID 12303 says:-1 > > clone3_cap_checkpoint_restore.c:88:clone3_cap_checkpoint_restore:[12302] Trying clone3() with CLONE_SET_TID to 12303 > > clone3_cap_checkpoint_restore.c:70:clone3_cap_checkpoint_restore:I am the parent (12302). My child's pid is 12303 > > clone3_cap_checkpoint_restore.c:63:clone3_cap_checkpoint_restore:I am the child, my PID is 12303 (expected 12303) > > clone3_cap_checkpoint_restore.c:90:clone3_cap_checkpoint_restore:[12302] clone3() with CLONE_SET_TID 12303 says:0 > > [ OK ] global.clone3_cap_checkpoint_restore > > [==========] 1 / 1 tests passed. > > [ PASSED ] > > > > Ok with this below being applied on top of it? > > > > diff --git a/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c b/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c > > index c0d83511cd28..9562425aa0a9 100644 > > --- a/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c > > +++ b/tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c > > @@ -38,7 +38,8 @@ static void child_exit(int ret) > > _exit(ret); > > } > > > > -static int call_clone3_set_tid(pid_t *set_tid, size_t set_tid_size) > > +static int call_clone3_set_tid(struct __test_metadata *_metadata, > > + pid_t *set_tid, size_t set_tid_size) > > { > > int status; > > pid_t pid = -1; > > @@ -51,7 +52,7 @@ static int call_clone3_set_tid(pid_t *set_tid, size_t set_tid_size) > > > > pid = sys_clone3(&args, sizeof(struct clone_args)); > > if (pid < 0) { > > - ksft_print_msg("%s - Failed to create new process\n", strerror(errno)); > > + TH_LOG("%s - Failed to create new process", strerror(errno)); > > return -errno; > > } > > > > @@ -59,18 +60,17 @@ static int call_clone3_set_tid(pid_t *set_tid, size_t set_tid_size) > > int ret; > > char tmp = 0; > > > > - ksft_print_msg > > - ("I am the child, my PID is %d (expected %d)\n", getpid(), set_tid[0]); > > + TH_LOG("I am the child, my PID is %d (expected %d)", getpid(), set_tid[0]); > > > > if (set_tid[0] != getpid()) > > child_exit(EXIT_FAILURE); > > child_exit(EXIT_SUCCESS); > > } > > > > - ksft_print_msg("I am the parent (%d). My child's pid is %d\n", getpid(), pid); > > + TH_LOG("I am the parent (%d). My child's pid is %d", getpid(), pid); > > > > if (waitpid(pid, &status, 0) < 0) { > > - ksft_print_msg("Child returned %s\n", strerror(errno)); > > + TH_LOG("Child returned %s", strerror(errno)); > > return -errno; > > } > > > > @@ -80,13 +80,14 @@ static int call_clone3_set_tid(pid_t *set_tid, size_t set_tid_size) > > return WEXITSTATUS(status); > > } > > > > -static int test_clone3_set_tid(pid_t *set_tid, size_t set_tid_size) > > +static int test_clone3_set_tid(struct __test_metadata *_metadata, > > + pid_t *set_tid, size_t set_tid_size) > > { > > int ret; > > > > - ksft_print_msg("[%d] Trying clone3() with CLONE_SET_TID to %d\n", getpid(), set_tid[0]); > > - ret = call_clone3_set_tid(set_tid, set_tid_size); > > - ksft_print_msg("[%d] clone3() with CLONE_SET_TID %d says:%d\n", getpid(), set_tid[0], ret); > > + TH_LOG("[%d] Trying clone3() with CLONE_SET_TID to %d", getpid(), set_tid[0]); > > + ret = call_clone3_set_tid(_metadata, set_tid, set_tid_size); > > + TH_LOG("[%d] clone3() with CLONE_SET_TID %d says:%d", getpid(), set_tid[0], ret); > > return ret; > > } > > > > @@ -144,7 +145,7 @@ TEST(clone3_cap_checkpoint_restore) > > test_clone3_supported(); > > > > EXPECT_EQ(getuid(), 0) > > - SKIP(return, "Skipping all tests as non-root\n"); > > + XFAIL(return, "Skipping all tests as non-root\n"); > > > > memset(&set_tid, 0, sizeof(set_tid)); > > > > @@ -162,16 +163,20 @@ TEST(clone3_cap_checkpoint_restore) > > > > ASSERT_EQ(set_capability(), 0) > > TH_LOG("Could not set CAP_CHECKPOINT_RESTORE"); > > - prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0); > > - setgid(1000); > > - setuid(1000); > > + > > + ASSERT_EQ(prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0), 0); > > + > > + EXPECT_EQ(setgid(65534), 0) > > + TH_LOG("Failed to setgid(65534)"); > > + ASSERT_EQ(setuid(65534), 0); > > + > > set_tid[0] = pid; > > /* This would fail without CAP_CHECKPOINT_RESTORE */ > > - ASSERT_EQ(test_clone3_set_tid(set_tid, 1), -EPERM); > > + ASSERT_EQ(test_clone3_set_tid(_metadata, set_tid, 1), -EPERM); > > ASSERT_EQ(set_capability(), 0) > > TH_LOG("Could not set CAP_CHECKPOINT_RESTORE"); > > /* This should work as we have CAP_CHECKPOINT_RESTORE as non-root */ > > - ASSERT_EQ(test_clone3_set_tid(set_tid, 1), 0); > > + ASSERT_EQ(test_clone3_set_tid(_metadata, set_tid, 1), 0); > > } > > > > Thanks for the changes. That looks much better. > > Can you fix the test directly or do you need a new reworked patch from us? No, I squashed this into your commit, added a comment about my changes, signed it off and am going to push it out for some more testing. Thanks! Christian