diff options
Diffstat (limited to 'test/syscalls')
| -rw-r--r-- | test/syscalls/linux/BUILD | 1 | ||||
| -rw-r--r-- | test/syscalls/linux/ptrace.cc | 1151 |
2 files changed, 1149 insertions, 3 deletions
diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD index 1a492bca3..f871426f0 100644 --- a/test/syscalls/linux/BUILD +++ b/test/syscalls/linux/BUILD @@ -1814,6 +1814,7 @@ cc_binary( "@com_google_absl//absl/flags:flag", "@com_google_absl//absl/time", gtest, + "//test/util:capability_util", "//test/util:file_descriptor", "//test/util:fs_util", "//test/util:logging", diff --git a/test/syscalls/linux/ptrace.cc b/test/syscalls/linux/ptrace.cc index 13c19d4a8..d1d7c6f84 100644 --- a/test/syscalls/linux/ptrace.cc +++ b/test/syscalls/linux/ptrace.cc @@ -15,7 +15,9 @@ #include <elf.h> #include <signal.h> #include <stddef.h> +#include <sys/prctl.h> #include <sys/ptrace.h> +#include <sys/socket.h> #include <sys/time.h> #include <sys/types.h> #include <sys/user.h> @@ -30,6 +32,7 @@ #include "absl/flags/flag.h" #include "absl/time/clock.h" #include "absl/time/time.h" +#include "test/util/capability_util.h" #include "test/util/fs_util.h" #include "test/util/logging.h" #include "test/util/memory_util.h" @@ -45,6 +48,49 @@ ABSL_FLAG(bool, ptrace_test_execve_child, false, "If true, run the " "PtraceExecveTest_Execve_GetRegs_PeekUser_SIGKILL_TraceClone_" "TraceExit child workload."); +ABSL_FLAG(bool, ptrace_test_trace_descendants_allowed, false, + "If set, run the child workload for " + "PtraceTest_TraceDescendantsAllowed."); +ABSL_FLAG(bool, ptrace_test_prctl_set_ptracer_pid, false, + "If set, run the child workload for PtraceTest_PrctlSetPtracerPID."); +ABSL_FLAG(bool, ptrace_test_prctl_set_ptracer_any, false, + "If set, run the child workload for PtraceTest_PrctlSetPtracerAny."); +ABSL_FLAG(bool, ptrace_test_prctl_clear_ptracer, false, + "If set, run the child workload for PtraceTest_PrctlClearPtracer."); +ABSL_FLAG(bool, ptrace_test_prctl_replace_ptracer, false, + "If set, run the child workload for PtraceTest_PrctlReplacePtracer."); +ABSL_FLAG(int, ptrace_test_prctl_replace_ptracer_tid, -1, + "Specifies the replacement tracer tid in the child workload for " + "PtraceTest_PrctlReplacePtracer."); +ABSL_FLAG(bool, ptrace_test_prctl_set_ptracer_and_exit_tracee_thread, false, + "If set, run the child workload for " + "PtraceTest_PrctlSetPtracerPersistsPastTraceeThreadExit."); +ABSL_FLAG(bool, ptrace_test_prctl_set_ptracer_and_exec_non_leader, false, + "If set, run the child workload for " + "PtraceTest_PrctlSetPtracerDoesNotPersistPastNonLeaderExec."); +ABSL_FLAG(bool, ptrace_test_prctl_set_ptracer_and_exit_tracer_thread, false, + "If set, run the child workload for " + "PtraceTest_PrctlSetPtracerDoesNotPersistPastTracerThreadExit."); +ABSL_FLAG(int, ptrace_test_prctl_set_ptracer_and_exit_tracer_thread_tid, -1, + "Specifies the tracee tid in the child workload for " + "PtraceTest_PrctlSetPtracerDoesNotPersistPastTracerThreadExit."); +ABSL_FLAG(bool, ptrace_test_prctl_set_ptracer_respects_tracer_thread_id, false, + "If set, run the child workload for PtraceTest_PrctlSetPtracePID."); +ABSL_FLAG(int, ptrace_test_prctl_set_ptracer_respects_tracer_thread_id_tid, -1, + "Specifies the thread tid to be traced in the child workload " + "for PtraceTest_PrctlSetPtracerRespectsTracerThreadID."); + +ABSL_FLAG(bool, ptrace_test_tracee, false, + "If true, run the tracee process for the " + "PrctlSetPtracerDoesNotPersistPastLeaderExec and " + "PrctlSetPtracerDoesNotPersistPastNonLeaderExec workloads."); +ABSL_FLAG(int, ptrace_test_trace_tid, -1, + "If set, run a process to ptrace attach to the thread with the " + "specified pid for the PrctlSetPtracerRespectsTracerThreadID " + "workload."); +ABSL_FLAG(int, ptrace_test_fd, -1, + "Specifies the fd used for communication between tracer and tracee " + "processes across exec."); namespace gvisor { namespace testing { @@ -78,10 +124,10 @@ void RaiseSignal(int sig) { TEST_PCHECK(tgkill(pid, tid, sig) == 0); } +constexpr char kYamaPtraceScopePath[] = "/proc/sys/kernel/yama/ptrace_scope"; + // Returns the Yama ptrace scope. PosixErrorOr<int> YamaPtraceScope() { - constexpr char kYamaPtraceScopePath[] = "/proc/sys/kernel/yama/ptrace_scope"; - ASSIGN_OR_RETURN_ERRNO(bool exists, Exists(kYamaPtraceScopePath)); if (!exists) { // File doesn't exist means no Yama, so the scope is disabled -> 0. @@ -99,6 +145,22 @@ PosixErrorOr<int> YamaPtraceScope() { return scope; } +int CheckPtraceAttach(pid_t pid) { + int ret = ptrace(PTRACE_ATTACH, pid, 0, 0); + MaybeSave(); + if (ret < 0) { + return ret; + } + + int status; + TEST_PCHECK(waitpid(pid, &status, 0) == pid); + MaybeSave(); + TEST_CHECK(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP); + TEST_PCHECK(ptrace(PTRACE_DETACH, pid, 0, 0) == 0); + MaybeSave(); + return 0; +} + TEST(PtraceTest, AttachSelf) { EXPECT_THAT(ptrace(PTRACE_ATTACH, gettid(), 0, 0), SyscallFailsWithErrno(EPERM)); @@ -111,10 +173,995 @@ TEST(PtraceTest, AttachSameThreadGroup) { }); } +TEST(PtraceTest, TraceParentNotAllowed) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) < 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + pid_t const child_pid = fork(); + if (child_pid == 0) { + TEST_CHECK(CheckPtraceAttach(getppid()) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); + } + ASSERT_THAT(child_pid, SyscallSucceeds()); + + int status; + ASSERT_THAT(waitpid(child_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; +} + +TEST(PtraceTest, TraceNonDescendantNotAllowed) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) < 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + TEST_CHECK(CheckPtraceAttach(tracee_pid) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); + } + EXPECT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0); + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +TEST(PtraceTest, TraceNonDescendantWithCapabilityAllowed) { + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_PTRACE))); + // Skip if disallowed by YAMA despite having CAP_SYS_PTRACE. + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) > 2); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + TEST_PCHECK(CheckPtraceAttach(tracee_pid) == 0); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0); + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +TEST(PtraceTest, TraceDescendantsAllowed) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) > 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use socket pair to communicate tids to this process from its grandchild. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_trace_descendants_allowed", + "--ptrace_test_fd", std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const child_pid = fork(); + if (child_pid == 0) { + // In child process. + TEST_PCHECK(close(sockets[1]) == 0); + pid_t const grandchild_pid = fork(); + if (grandchild_pid == 0) { + // This test will create a new thread in the grandchild process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + TEST_PCHECK(grandchild_pid > 0); + MaybeSave(); + + // Wait for grandchild. Our parent process will kill it once it's done. + int status; + TEST_PCHECK(waitpid(grandchild_pid, &status, 0) == grandchild_pid); + TEST_CHECK(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL); + MaybeSave(); + _exit(0); + } + ASSERT_THAT(child_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + // We should be able to attach to any thread in the grandchild. + pid_t grandchild_tid1, grandchild_tid2; + ASSERT_THAT(read(sockets[1], &grandchild_tid1, sizeof(grandchild_tid1)), + SyscallSucceedsWithValue(sizeof(grandchild_tid1))); + ASSERT_THAT(read(sockets[1], &grandchild_tid2, sizeof(grandchild_tid2)), + SyscallSucceedsWithValue(sizeof(grandchild_tid2))); + + EXPECT_THAT(CheckPtraceAttach(grandchild_tid1), SyscallSucceeds()); + EXPECT_THAT(CheckPtraceAttach(grandchild_tid2), SyscallSucceeds()); + + // Clean up grandchild. + ASSERT_THAT(kill(grandchild_tid1, SIGKILL), SyscallSucceeds()); + + // Clean up child. + int status; + ASSERT_THAT(waitpid(child_pid, &status, 0), + SyscallSucceedsWithValue(child_pid)); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; +} + +[[noreturn]] void RunTraceDescendantsAllowed(int fd) { + // Let the tracer know our tid through the socket fd. + pid_t const tid = gettid(); + TEST_PCHECK(write(fd, &tid, sizeof(tid)) == sizeof(tid)); + MaybeSave(); + + ScopedThread t([fd] { + // See if any arbitrary thread (whose tid differs from the process id) can + // be traced as well. + pid_t const tid = gettid(); + TEST_PCHECK(write(fd, &tid, sizeof(tid)) == sizeof(tid)); + MaybeSave(); + while (true) { + SleepSafe(absl::Seconds(1)); + } + }); + + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +TEST(PtraceTest, PrctlSetPtracerInvalidPID) { + // EINVAL should also be returned if PR_SET_PTRACER is not supported. + EXPECT_THAT(prctl(PR_SET_PTRACER, 123456789), SyscallFailsWithErrno(EINVAL)); +} + +TEST(PtraceTest, PrctlSetPtracerPID) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_prctl_set_ptracer_pid", + "--ptrace_test_fd", std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + TEST_PCHECK(close(sockets[1]) == 0); + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until tracee has called prctl. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_PCHECK(CheckPtraceAttach(tracee_pid) == 0); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0); + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlSetPtracerPID(int fd) { + ScopedThread t([fd] { + // Perform prctl in a separate thread to verify that it is process-wide. + TEST_PCHECK(prctl(PR_SET_PTRACER, getppid()) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(fd, "x", 1) == 1); + MaybeSave(); + }); + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +TEST(PtraceTest, PrctlSetPtracerAny) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_prctl_set_ptracer_any", + "--ptrace_test_fd", std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + TEST_PCHECK(close(sockets[1]) == 0); + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until tracee has called prctl. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_PCHECK(CheckPtraceAttach(tracee_pid) == 0); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlSetPtracerAny(int fd) { + ScopedThread t([fd] { + // Perform prctl in a separate thread to verify that it is process-wide. + TEST_PCHECK(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(fd, "x", 1) == 1); + MaybeSave(); + }); + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +TEST(PtraceTest, PrctlClearPtracer) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_prctl_clear_ptracer", "--ptrace_test_fd", + std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + TEST_PCHECK(close(sockets[1]) == 0); + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until tracee has called prctl. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_CHECK(CheckPtraceAttach(tracee_pid) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlClearPtracer(int fd) { + ScopedThread t([fd] { + // Perform prctl in a separate thread to verify that it is process-wide. + TEST_PCHECK(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) == 0); + MaybeSave(); + TEST_PCHECK(prctl(PR_SET_PTRACER, 0) == 0); + MaybeSave(); + // Indicate that the prctl has been set/cleared. + TEST_PCHECK(write(fd, "x", 1) == 1); + MaybeSave(); + }); + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +TEST(PtraceTest, PrctlReplacePtracer) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + pid_t const unused_pid = fork(); + if (unused_pid == 0) { + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(unused_pid, SyscallSucceeds()); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", + "--ptrace_test_prctl_replace_ptracer", + "--ptrace_test_prctl_replace_ptracer_tid", + std::to_string(unused_pid), + "--ptrace_test_fd", + std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + TEST_PCHECK(close(sockets[1]) == 0); + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until tracee has called prctl. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_CHECK(CheckPtraceAttach(tracee_pid) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; + + // Clean up unused. + ASSERT_THAT(kill(unused_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(unused_pid, &status, 0), + SyscallSucceedsWithValue(unused_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlReplacePtracer(int new_tracer_pid, int fd) { + TEST_PCHECK(prctl(PR_SET_PTRACER, getppid()) == 0); + MaybeSave(); + + ScopedThread t([new_tracer_pid, fd] { + TEST_PCHECK(prctl(PR_SET_PTRACER, new_tracer_pid) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(fd, "x", 1) == 1); + MaybeSave(); + }); + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +// Tests that YAMA exceptions store tracees by thread group leader. Exceptions +// are preserved even after the tracee thread exits, as long as the tracee's +// thread group leader is still around. +TEST(PtraceTest, PrctlSetPtracerPersistsPastTraceeThreadExit) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", + "--ptrace_test_prctl_set_ptracer_and_exit_tracee_thread", + "--ptrace_test_fd", std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + TEST_PCHECK(close(sockets[1]) == 0); + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until the tracee thread calling prctl has terminated. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_PCHECK(CheckPtraceAttach(tracee_pid) == 0); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlSetPtracerPersistsPastTraceeThreadExit(int fd) { + ScopedThread t([] { + TEST_PCHECK(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) == 0); + MaybeSave(); + }); + t.Join(); + // Indicate that thread setting the prctl has exited. + TEST_PCHECK(write(fd, "x", 1) == 1); + MaybeSave(); + + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +// Tests that YAMA exceptions store tracees by thread group leader. Exceptions +// are preserved across exec as long as the thread group leader does not change, +// even if the tracee thread is terminated. +TEST(PtraceTest, PrctlSetPtracerPersistsPastLeaderExec) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_tracee", "--ptrace_test_fd", + std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + TEST_PCHECK(close(sockets[1]) == 0); + TEST_PCHECK(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) == 0); + MaybeSave(); + + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until the tracee has exec'd. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_PCHECK(CheckPtraceAttach(tracee_pid) == 0); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunTracee(int fd) { + // Indicate that we have exec'd. + TEST_PCHECK(write(fd, "x", 1) == 1); + MaybeSave(); + + while (true) { + SleepSafe(absl::Seconds(1)); + } +} + +// Tests that YAMA exceptions store tracees by thread group leader. Exceptions +// are cleared if the tracee process's thread group leader is terminated by +// exec. +TEST(PtraceTest, PrctlSetPtracerDoesNotPersistPastNonLeaderExec) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_prctl_set_ptracer_and_exec_non_leader", + "--ptrace_test_fd", std::to_string(sockets[0])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + TEST_PCHECK(close(sockets[1]) == 0); + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until the tracee has exec'd. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_CHECK(CheckPtraceAttach(tracee_pid) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlSetPtracerDoesNotPersistPastNonLeaderExec(int fd) { + ScopedThread t([fd] { + TEST_PCHECK(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) == 0); + MaybeSave(); + + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_tracee", "--ptrace_test_fd", + std::to_string(fd)}; + char* const* const child_argv = owned_child_argv.get(); + + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + }); + t.Join(); + TEST_CHECK_MSG(false, "Survived execve? (main)"); + _exit(1); +} + +// Tests that YAMA exceptions store the tracer itself rather than the thread +// group leader. Exceptions are cleared when the tracer task exits, rather than +// when its thread group leader exits. +TEST(PtraceTest, PrctlSetPtracerDoesNotPersistPastTracerThreadExit) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + TEST_PCHECK(close(sockets[1]) == 0); + pid_t tracer_tid; + TEST_PCHECK(read(sockets[0], &tracer_tid, sizeof(tracer_tid)) == + sizeof(tracer_tid)); + MaybeSave(); + + TEST_PCHECK(prctl(PR_SET_PTRACER, tracer_tid) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(sockets[0], "x", 1) == 1); + MaybeSave(); + + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", + "--ptrace_test_prctl_set_ptracer_and_exit_tracer_thread", + "--ptrace_test_prctl_set_ptracer_and_exit_tracer_thread_tid", + std::to_string(tracee_pid), + "--ptrace_test_fd", + std::to_string(sockets[1])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlSetPtracerDoesNotPersistPastTracerThreadExit( + int tracee_tid, int fd) { + TEST_PCHECK(SetCapability(CAP_SYS_PTRACE, false).ok()); + + ScopedThread t([fd] { + pid_t const tracer_tid = gettid(); + TEST_PCHECK(write(fd, &tracer_tid, sizeof(tracer_tid)) == + sizeof(tracer_tid)); + + // Wait until the prctl has been set. + char done; + TEST_PCHECK(read(fd, &done, 1) == 1); + MaybeSave(); + }); + t.Join(); + + // Sleep for a bit before verifying the invalidation. The thread exit above + // should cause the ptrace exception to be invalidated, but in Linux, this is + // not done immediately. The YAMA exception is dropped during + // __put_task_struct(), which occurs (at the earliest) one RCU grace period + // after exit_notify() ==> release_task(). + SleepSafe(absl::Milliseconds(100)); + + TEST_CHECK(CheckPtraceAttach(tracee_tid) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); +} + +// Tests that YAMA exceptions store the tracer thread itself rather than the +// thread group leader. Exceptions are preserved across exec in the tracer +// thread, even if the thread group leader is terminated. +TEST(PtraceTest, PrctlSetPtracerRespectsTracerThreadID) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + TEST_PCHECK(close(sockets[1]) == 0); + pid_t tracer_tid; + TEST_PCHECK(read(sockets[0], &tracer_tid, sizeof(tracer_tid)) == + sizeof(tracer_tid)); + MaybeSave(); + + TEST_PCHECK(prctl(PR_SET_PTRACER, tracer_tid) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(sockets[0], "x", 1) == 1); + MaybeSave(); + + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + // Allocate vector before forking (not async-signal-safe). + ExecveArray const owned_child_argv = { + "/proc/self/exe", + "--ptrace_test_prctl_set_ptracer_respects_tracer_thread_id", + "--ptrace_test_prctl_set_ptracer_respects_tracer_thread_id_tid", + std::to_string(tracee_pid), + "--ptrace_test_fd", + std::to_string(sockets[1])}; + char* const* const child_argv = owned_child_argv.get(); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // This test will create a new thread in the child process. + // pthread_create(2) isn't async-signal-safe, so we execve() first. + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +[[noreturn]] void RunPrctlSetPtracerRespectsTracerThreadID(int tracee_tid, + int fd) { + // Create a separate thread for tracing (i.e., not the thread group + // leader). After the subsequent execve(), the current thread group leader + // will no longer be exist, but the YAMA exception installed with this + // thread should still be valid. + ScopedThread t([tracee_tid, fd] { + pid_t const tracer_tid = gettid(); + TEST_PCHECK(write(fd, &tracer_tid, sizeof(tracer_tid))); + MaybeSave(); + + // Wait until the tracee has made the PR_SET_PTRACER prctl. + char done; + TEST_PCHECK(read(fd, &done, 1) == 1); + MaybeSave(); + + ExecveArray const owned_child_argv = { + "/proc/self/exe", "--ptrace_test_trace_tid", std::to_string(tracee_tid), + "--ptrace_test_fd", std::to_string(fd)}; + char* const* const child_argv = owned_child_argv.get(); + + execve(child_argv[0], child_argv, /* envp = */ nullptr); + TEST_PCHECK_MSG(false, "Survived execve to test child"); + }); + t.Join(); + TEST_CHECK_MSG(false, "Survived execve? (main)"); + _exit(1); +} + +[[noreturn]] void RunTraceTID(int tracee_tid, int fd) { + TEST_PCHECK(SetCapability(CAP_SYS_PTRACE, false).ok()); + TEST_PCHECK(CheckPtraceAttach(tracee_tid) == 0); + _exit(0); +} + +// Tests that removing a YAMA exception does not affect a tracer that is already +// attached. +TEST(PtraceTest, PrctlClearPtracerDoesNotAffectCurrentTracer) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Use sockets to synchronize between tracer and tracee. + int sockets[2]; + ASSERT_THAT(socketpair(AF_UNIX, SOCK_STREAM, 0, sockets), SyscallSucceeds()); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + TEST_PCHECK(close(sockets[1]) == 0); + TEST_PCHECK(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(sockets[0], "x", 1) == 1); + MaybeSave(); + + // Wait until tracer has attached before clearing PR_SET_PTRACER. + char done; + TEST_PCHECK(read(sockets[0], &done, 1) == 1); + MaybeSave(); + + TEST_PCHECK(prctl(PR_SET_PTRACER, 0) == 0); + MaybeSave(); + // Indicate that the prctl has been set. + TEST_PCHECK(write(sockets[0], "x", 1) == 1); + MaybeSave(); + + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + ASSERT_THAT(close(sockets[0]), SyscallSucceeds()); + + std::string mem_path = "/proc/" + std::to_string(tracee_pid) + "/mem"; + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + // Wait until tracee has called prctl, or else we won't be able to attach. + char done; + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + + TEST_PCHECK(ptrace(PTRACE_ATTACH, tracee_pid, 0, 0) == 0); + MaybeSave(); + // Indicate that we have attached. + TEST_PCHECK(write(sockets[1], &done, 1) == 1); + MaybeSave(); + + // Block until tracee enters signal-delivery-stop as a result of the + // SIGSTOP sent by PTRACE_ATTACH. + int status; + TEST_PCHECK(waitpid(tracee_pid, &status, 0) == tracee_pid); + MaybeSave(); + TEST_CHECK(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP); + MaybeSave(); + + TEST_PCHECK(ptrace(PTRACE_CONT, tracee_pid, 0, 0) == 0); + MaybeSave(); + + // Wait until tracee has cleared PR_SET_PTRACER. Even though it was cleared, + // we should still be able to access /proc/[pid]/mem because we are already + // attached. + TEST_PCHECK(read(sockets[1], &done, 1) == 1); + MaybeSave(); + TEST_PCHECK(open(mem_path.c_str(), O_RDONLY) != -1); + MaybeSave(); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + +TEST(PtraceTest, PrctlNotInherited) { + SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) != 1); + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + + // Allow any ptracer. This should not affect the child processes. + ASSERT_THAT(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY), SyscallSucceeds()); + + pid_t const tracee_pid = fork(); + if (tracee_pid == 0) { + while (true) { + SleepSafe(absl::Seconds(1)); + } + } + ASSERT_THAT(tracee_pid, SyscallSucceeds()); + + pid_t const tracer_pid = fork(); + if (tracer_pid == 0) { + TEST_CHECK(CheckPtraceAttach(tracee_pid) == -1); + TEST_PCHECK(errno == EPERM); + _exit(0); + } + ASSERT_THAT(tracer_pid, SyscallSucceeds()); + + // Clean up tracer. + int status; + ASSERT_THAT(waitpid(tracer_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Clean up tracee. + ASSERT_THAT(kill(tracee_pid, SIGKILL), SyscallSucceeds()); + ASSERT_THAT(waitpid(tracee_pid, &status, 0), + SyscallSucceedsWithValue(tracee_pid)); + EXPECT_TRUE(WIFSIGNALED(status) && WTERMSIG(status) == SIGKILL) + << " status " << status; +} + TEST(PtraceTest, AttachParent_PeekData_PokeData_SignalSuppression) { // Yama prevents attaching to a parent. Skip the test if the scope is anything // except disabled. - SKIP_IF(ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()) > 0); + const int yama_scope = ASSERT_NO_ERRNO_AND_VALUE(YamaPtraceScope()); + SKIP_IF(yama_scope > 1); + if (yama_scope == 1) { + // Allow child to trace us. + ASSERT_THAT(prctl(PR_SET_PTRACER, PR_SET_PTRACER_ANY), SyscallSucceeds()); + } // Test PTRACE_POKE/PEEKDATA on both anonymous and file mappings. const auto file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); @@ -1238,6 +2285,46 @@ TEST(PtraceTest, SeizeSetOptions) { << " status " << status; } +TEST(PtraceTest, SetYAMAPtraceScope) { + SKIP_IF(IsRunningWithVFS1()); + + // Do not modify the ptrace scope on the host. + SKIP_IF(!IsRunningOnGvisor()); + SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN))); + + const FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE( + Open(std::string(kYamaPtraceScopePath), O_RDWR)); + + ASSERT_THAT(write(fd.get(), "0", 1), SyscallSucceedsWithValue(1)); + + ASSERT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceeds()); + std::vector<char> buf(10); + EXPECT_THAT(read(fd.get(), buf.data(), buf.size()), SyscallSucceeds()); + EXPECT_STREQ(buf.data(), "0\n"); + + // Test that a child can attach to its parent when ptrace_scope is 0. + ASSERT_NO_ERRNO(SetCapability(CAP_SYS_PTRACE, false)); + pid_t const child_pid = fork(); + if (child_pid == 0) { + TEST_PCHECK(CheckPtraceAttach(getppid()) == 0); + _exit(0); + } + ASSERT_THAT(child_pid, SyscallSucceeds()); + + int status; + ASSERT_THAT(waitpid(child_pid, &status, 0), SyscallSucceeds()); + EXPECT_TRUE(WIFEXITED(status) && WEXITSTATUS(status) == 0) + << " status " << status; + + // Set ptrace_scope back to 1 (and try writing with a newline). + ASSERT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceeds()); + ASSERT_THAT(write(fd.get(), "1\n", 2), SyscallSucceedsWithValue(2)); + + ASSERT_THAT(lseek(fd.get(), 0, SEEK_SET), SyscallSucceeds()); + EXPECT_THAT(read(fd.get(), buf.data(), buf.size()), SyscallSucceeds()); + EXPECT_STREQ(buf.data(), "1\n"); +} + } // namespace } // namespace testing @@ -1250,5 +2337,63 @@ int main(int argc, char** argv) { gvisor::testing::RunExecveChild(); } + int fd = absl::GetFlag(FLAGS_ptrace_test_fd); + + if (absl::GetFlag(FLAGS_ptrace_test_trace_descendants_allowed)) { + gvisor::testing::RunTraceDescendantsAllowed(fd); + } + + if (absl::GetFlag(FLAGS_ptrace_test_prctl_set_ptracer_pid)) { + gvisor::testing::RunPrctlSetPtracerPID(fd); + } + + if (absl::GetFlag(FLAGS_ptrace_test_prctl_set_ptracer_any)) { + gvisor::testing::RunPrctlSetPtracerAny(fd); + } + + if (absl::GetFlag(FLAGS_ptrace_test_prctl_clear_ptracer)) { + gvisor::testing::RunPrctlClearPtracer(fd); + } + + if (absl::GetFlag(FLAGS_ptrace_test_prctl_replace_ptracer)) { + gvisor::testing::RunPrctlReplacePtracer( + absl::GetFlag(FLAGS_ptrace_test_prctl_replace_ptracer_tid), fd); + } + + if (absl::GetFlag( + FLAGS_ptrace_test_prctl_set_ptracer_and_exit_tracee_thread)) { + gvisor::testing::RunPrctlSetPtracerPersistsPastTraceeThreadExit(fd); + } + + if (absl::GetFlag(FLAGS_ptrace_test_prctl_set_ptracer_and_exec_non_leader)) { + gvisor::testing::RunPrctlSetPtracerDoesNotPersistPastNonLeaderExec( + fd); + } + + if (absl::GetFlag( + FLAGS_ptrace_test_prctl_set_ptracer_and_exit_tracer_thread)) { + gvisor::testing::RunPrctlSetPtracerDoesNotPersistPastTracerThreadExit( + absl::GetFlag( + FLAGS_ptrace_test_prctl_set_ptracer_and_exit_tracer_thread_tid), + fd); + } + + if (absl::GetFlag( + FLAGS_ptrace_test_prctl_set_ptracer_respects_tracer_thread_id)) { + gvisor::testing::RunPrctlSetPtracerRespectsTracerThreadID( + absl::GetFlag( + FLAGS_ptrace_test_prctl_set_ptracer_respects_tracer_thread_id_tid), + fd); + } + + if (absl::GetFlag(FLAGS_ptrace_test_tracee)) { + gvisor::testing::RunTracee(fd); + } + + int pid = absl::GetFlag(FLAGS_ptrace_test_trace_tid); + if (pid != -1) { + gvisor::testing::RunTraceTID(pid, fd); + } + return gvisor::testing::RunAllTests(); } |