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); } TEST_HARNESS_MAIN
