[linux-next,v9,7/7] selftests/ptrace: add a test case for PTRACE_GET_SYSCALL_INFO
diff mbox series

Message ID 20190408174236.GH11889@altlinux.org
State New
Headers show
Series
  • ptrace: add PTRACE_GET_SYSCALL_INFO request
Related show

Commit Message

Dmitry V. Levin April 8, 2019, 5:42 p.m. UTC
Check whether PTRACE_GET_SYSCALL_INFO semantics implemented in the kernel
matches userspace expectations.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Elvira Khabirova <lineprinter@altlinux.org>
Cc: Eugene Syromyatnikov <esyr@redhat.com>
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
---

Notes:
    v9: unchanged
    v8: unchanged
    v7: unchanged
    v6: made PTRACE_GET_SYSCALL_INFO return value checks strict
    v5: initial revision

 tools/testing/selftests/ptrace/.gitignore     |   1 +
 tools/testing/selftests/ptrace/Makefile       |   2 +-
 .../selftests/ptrace/get_syscall_info.c       | 271 ++++++++++++++++++
 3 files changed, 273 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/ptrace/get_syscall_info.c

Comments

shuah April 8, 2019, 5:51 p.m. UTC | #1
On 4/8/19 11:42 AM, Dmitry V. Levin wrote:
> Check whether PTRACE_GET_SYSCALL_INFO semantics implemented in the kernel
> matches userspace expectations.
> 
> Cc: Oleg Nesterov <oleg@redhat.com>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Shuah Khan <shuah@kernel.org>
> Cc: Elvira Khabirova <lineprinter@altlinux.org>
> Cc: Eugene Syromyatnikov <esyr@redhat.com>
> Cc: linux-kselftest@vger.kernel.org
> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> ---
> 
> Notes:
>      v9: unchanged
>      v8: unchanged
>      v7: unchanged
>      v6: made PTRACE_GET_SYSCALL_INFO return value checks strict
>      v5: initial revision
> 
>   tools/testing/selftests/ptrace/.gitignore     |   1 +
>   tools/testing/selftests/ptrace/Makefile       |   2 +-
>   .../selftests/ptrace/get_syscall_info.c       | 271 ++++++++++++++++++
>   3 files changed, 273 insertions(+), 1 deletion(-)
>   create mode 100644 tools/testing/selftests/ptrace/get_syscall_info.c
> 
> diff --git a/tools/testing/selftests/ptrace/.gitignore b/tools/testing/selftests/ptrace/.gitignore
> index b3e59d41fd82..cfcc49a7def7 100644
> --- a/tools/testing/selftests/ptrace/.gitignore
> +++ b/tools/testing/selftests/ptrace/.gitignore
> @@ -1 +1,2 @@
> +get_syscall_info
>   peeksiginfo
> diff --git a/tools/testing/selftests/ptrace/Makefile b/tools/testing/selftests/ptrace/Makefile
> index 8a2bc5562179..4bc550b6b845 100644
> --- a/tools/testing/selftests/ptrace/Makefile
> +++ b/tools/testing/selftests/ptrace/Makefile
> @@ -1,5 +1,5 @@
>   CFLAGS += -iquote../../../../include/uapi -Wall
>   
> -TEST_GEN_PROGS := peeksiginfo
> +TEST_GEN_PROGS := get_syscall_info peeksiginfo
>   
>   include ../lib.mk
> diff --git a/tools/testing/selftests/ptrace/get_syscall_info.c b/tools/testing/selftests/ptrace/get_syscall_info.c
> new file mode 100644
> index 000000000000..28e972825b74
> --- /dev/null
> +++ b/tools/testing/selftests/ptrace/get_syscall_info.c
> @@ -0,0 +1,271 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later
> + *

This should be just GPL-2.0+

The rest looks good to me. Assuming this patch has dependency on the
rest of the patches in this series and once the above change is made:

Acked-by: Shuah Khan <shuah@kernel.org>

thnaks,
-- Shuah
Dmitry V. Levin April 8, 2019, 6:04 p.m. UTC | #2
On Mon, Apr 08, 2019 at 11:51:45AM -0600, shuah wrote:
> On 4/8/19 11:42 AM, Dmitry V. Levin wrote:
> > Check whether PTRACE_GET_SYSCALL_INFO semantics implemented in the kernel
> > matches userspace expectations.
> > 
> > Cc: Oleg Nesterov <oleg@redhat.com>
> > Cc: Andy Lutomirski <luto@kernel.org>
> > Cc: Shuah Khan <shuah@kernel.org>
> > Cc: Elvira Khabirova <lineprinter@altlinux.org>
> > Cc: Eugene Syromyatnikov <esyr@redhat.com>
> > Cc: linux-kselftest@vger.kernel.org
> > Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
> > ---
> > 
> > Notes:
> >      v9: unchanged
> >      v8: unchanged
> >      v7: unchanged
> >      v6: made PTRACE_GET_SYSCALL_INFO return value checks strict
> >      v5: initial revision
> > 
> >   tools/testing/selftests/ptrace/.gitignore     |   1 +
> >   tools/testing/selftests/ptrace/Makefile       |   2 +-
> >   .../selftests/ptrace/get_syscall_info.c       | 271 ++++++++++++++++++
> >   3 files changed, 273 insertions(+), 1 deletion(-)
> >   create mode 100644 tools/testing/selftests/ptrace/get_syscall_info.c
> > 
> > diff --git a/tools/testing/selftests/ptrace/.gitignore b/tools/testing/selftests/ptrace/.gitignore
> > index b3e59d41fd82..cfcc49a7def7 100644
> > --- a/tools/testing/selftests/ptrace/.gitignore
> > +++ b/tools/testing/selftests/ptrace/.gitignore
> > @@ -1 +1,2 @@
> > +get_syscall_info
> >   peeksiginfo
> > diff --git a/tools/testing/selftests/ptrace/Makefile b/tools/testing/selftests/ptrace/Makefile
> > index 8a2bc5562179..4bc550b6b845 100644
> > --- a/tools/testing/selftests/ptrace/Makefile
> > +++ b/tools/testing/selftests/ptrace/Makefile
> > @@ -1,5 +1,5 @@
> >   CFLAGS += -iquote../../../../include/uapi -Wall
> >   
> > -TEST_GEN_PROGS := peeksiginfo
> > +TEST_GEN_PROGS := get_syscall_info peeksiginfo
> >   
> >   include ../lib.mk
> > diff --git a/tools/testing/selftests/ptrace/get_syscall_info.c b/tools/testing/selftests/ptrace/get_syscall_info.c
> > new file mode 100644
> > index 000000000000..28e972825b74
> > --- /dev/null
> > +++ b/tools/testing/selftests/ptrace/get_syscall_info.c
> > @@ -0,0 +1,271 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later
> > + *
> 
> This should be just GPL-2.0+

LICENSES/preferred/GPL-2.0 says these variants are equivalent:
"
[...]
Valid-License-Identifier: GPL-2.0+
Valid-License-Identifier: GPL-2.0-or-later
[...]
  For 'GNU General Public License (GPL) version 2 or any later version' use:
    SPDX-License-Identifier: GPL-2.0+
  or
    SPDX-License-Identifier: GPL-2.0-or-later
"

The usage statistics shows that GPL-2.0+ is more popular in the kernel
tree than GPL-2.0-or-later, though.

> The rest looks good to me. Assuming this patch has dependency on the
> rest of the patches in this series and once the above change is made:

No problem, I'm fine with either variant of the license identifier.

> Acked-by: Shuah Khan <shuah@kernel.org>

Thanks,

Patch
diff mbox series

diff --git a/tools/testing/selftests/ptrace/.gitignore b/tools/testing/selftests/ptrace/.gitignore
index b3e59d41fd82..cfcc49a7def7 100644
--- a/tools/testing/selftests/ptrace/.gitignore
+++ b/tools/testing/selftests/ptrace/.gitignore
@@ -1 +1,2 @@ 
+get_syscall_info
 peeksiginfo
diff --git a/tools/testing/selftests/ptrace/Makefile b/tools/testing/selftests/ptrace/Makefile
index 8a2bc5562179..4bc550b6b845 100644
--- a/tools/testing/selftests/ptrace/Makefile
+++ b/tools/testing/selftests/ptrace/Makefile
@@ -1,5 +1,5 @@ 
 CFLAGS += -iquote../../../../include/uapi -Wall
 
-TEST_GEN_PROGS := peeksiginfo
+TEST_GEN_PROGS := get_syscall_info peeksiginfo
 
 include ../lib.mk
diff --git a/tools/testing/selftests/ptrace/get_syscall_info.c b/tools/testing/selftests/ptrace/get_syscall_info.c
new file mode 100644
index 000000000000..28e972825b74
--- /dev/null
+++ b/tools/testing/selftests/ptrace/get_syscall_info.c
@@ -0,0 +1,271 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * Copyright (c) 2018 Dmitry V. Levin <ldv@altlinux.org>
+ * All rights reserved.
+ *
+ * Check whether PTRACE_GET_SYSCALL_INFO semantics implemented in the kernel
+ * matches userspace expectations.
+ */
+
+#include "../kselftest_harness.h"
+#include <err.h>
+#include <signal.h>
+#include <asm/unistd.h>
+#include "linux/ptrace.h"
+
+static int
+kill_tracee(pid_t pid)
+{
+	if (!pid)
+		return 0;
+
+	int saved_errno = errno;
+
+	int rc = kill(pid, SIGKILL);
+
+	errno = saved_errno;
+	return rc;
+}
+
+static long
+sys_ptrace(int request, pid_t pid, unsigned long addr, unsigned long data)
+{
+	return syscall(__NR_ptrace, request, pid, addr, data);
+}
+
+#define LOG_KILL_TRACEE(fmt, ...)				\
+	do {							\
+		kill_tracee(pid);				\
+		TH_LOG("wait #%d: " fmt,			\
+		       ptrace_stop, ##__VA_ARGS__);		\
+	} while (0)
+
+TEST(get_syscall_info)
+{
+	static const unsigned long args[][7] = {
+		/* a sequence of architecture-agnostic syscalls */
+		{
+			__NR_chdir,
+			(unsigned long) "",
+			0xbad1fed1,
+			0xbad2fed2,
+			0xbad3fed3,
+			0xbad4fed4,
+			0xbad5fed5
+		},
+		{
+			__NR_gettid,
+			0xcaf0bea0,
+			0xcaf1bea1,
+			0xcaf2bea2,
+			0xcaf3bea3,
+			0xcaf4bea4,
+			0xcaf5bea5
+		},
+		{
+			__NR_exit_group,
+			0,
+			0xfac1c0d1,
+			0xfac2c0d2,
+			0xfac3c0d3,
+			0xfac4c0d4,
+			0xfac5c0d5
+		}
+	};
+	const unsigned long *exp_args;
+
+	pid_t pid = fork();
+
+	ASSERT_LE(0, pid) {
+		TH_LOG("fork: %m");
+	}
+
+	if (pid == 0) {
+		/* get the pid before PTRACE_TRACEME */
+		pid = getpid();
+		ASSERT_EQ(0, sys_ptrace(PTRACE_TRACEME, 0, 0, 0)) {
+			TH_LOG("PTRACE_TRACEME: %m");
+		}
+		ASSERT_EQ(0, kill(pid, SIGSTOP)) {
+			/* cannot happen */
+			TH_LOG("kill SIGSTOP: %m");
+		}
+		for (unsigned int i = 0; i < ARRAY_SIZE(args); ++i) {
+			syscall(args[i][0],
+				args[i][1], args[i][2], args[i][3],
+				args[i][4], args[i][5], args[i][6]);
+		}
+		/* unreachable */
+		_exit(1);
+	}
+
+	const struct {
+		unsigned int is_error;
+		int rval;
+	} *exp_param, exit_param[] = {
+		{ 1, -ENOENT },	/* chdir */
+		{ 0, pid }	/* gettid */
+	};
+
+	unsigned int ptrace_stop;
+
+	for (ptrace_stop = 0; ; ++ptrace_stop) {
+		struct ptrace_syscall_info info = {
+			.op = 0xff	/* invalid PTRACE_SYSCALL_INFO_* op */
+		};
+		const size_t size = sizeof(info);
+		const int expected_none_size =
+			(void *) &info.entry - (void *) &info;
+		const int expected_entry_size =
+			(void *) &info.entry.args[6] - (void *) &info;
+		const int expected_exit_size =
+			(void *) (&info.exit.is_error + 1) -
+			(void *) &info;
+		int status;
+		long rc;
+
+		ASSERT_EQ(pid, wait(&status)) {
+			/* cannot happen */
+			LOG_KILL_TRACEE("wait: %m");
+		}
+		if (WIFEXITED(status)) {
+			pid = 0;	/* the tracee is no more */
+			ASSERT_EQ(0, WEXITSTATUS(status));
+			break;
+		}
+		ASSERT_FALSE(WIFSIGNALED(status)) {
+			pid = 0;	/* the tracee is no more */
+			LOG_KILL_TRACEE("unexpected signal %u",
+					WTERMSIG(status));
+		}
+		ASSERT_TRUE(WIFSTOPPED(status)) {
+			/* cannot happen */
+			LOG_KILL_TRACEE("unexpected wait status %#x", status);
+		}
+
+		switch (WSTOPSIG(status)) {
+		case SIGSTOP:
+			ASSERT_EQ(0, ptrace_stop) {
+				LOG_KILL_TRACEE("unexpected signal stop");
+			}
+			ASSERT_EQ(0, sys_ptrace(PTRACE_SETOPTIONS, pid, 0,
+						PTRACE_O_TRACESYSGOOD)) {
+				LOG_KILL_TRACEE("PTRACE_SETOPTIONS: %m");
+			}
+			ASSERT_LT(0, (rc = sys_ptrace(PTRACE_GET_SYSCALL_INFO,
+						      pid, size,
+						      (unsigned long) &info))) {
+				LOG_KILL_TRACEE("PTRACE_GET_SYSCALL_INFO: %m");
+			}
+			ASSERT_EQ(expected_none_size, rc) {
+				LOG_KILL_TRACEE("signal stop mismatch");
+			}
+			ASSERT_EQ(PTRACE_SYSCALL_INFO_NONE, info.op) {
+				LOG_KILL_TRACEE("signal stop mismatch");
+			}
+			ASSERT_TRUE(info.arch) {
+				LOG_KILL_TRACEE("signal stop mismatch");
+			}
+			ASSERT_TRUE(info.instruction_pointer) {
+				LOG_KILL_TRACEE("signal stop mismatch");
+			}
+			ASSERT_TRUE(info.stack_pointer) {
+				LOG_KILL_TRACEE("signal stop mismatch");
+			}
+			break;
+
+		case SIGTRAP | 0x80:
+			ASSERT_LT(0, (rc = sys_ptrace(PTRACE_GET_SYSCALL_INFO,
+						      pid, size,
+						      (unsigned long) &info))) {
+				LOG_KILL_TRACEE("PTRACE_GET_SYSCALL_INFO: %m");
+			}
+			switch (ptrace_stop) {
+			case 1: /* entering chdir */
+			case 3: /* entering gettid */
+			case 5: /* entering exit_group */
+				exp_args = args[ptrace_stop / 2];
+				ASSERT_EQ(expected_entry_size, rc) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(PTRACE_SYSCALL_INFO_ENTRY, info.op) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_TRUE(info.arch) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_TRUE(info.instruction_pointer) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_TRUE(info.stack_pointer) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[0], info.entry.nr) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[1], info.entry.args[0]) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[2], info.entry.args[1]) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[3], info.entry.args[2]) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[4], info.entry.args[3]) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[5], info.entry.args[4]) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				ASSERT_EQ(exp_args[6], info.entry.args[5]) {
+					LOG_KILL_TRACEE("entry stop mismatch");
+				}
+				break;
+			case 2: /* exiting chdir */
+			case 4: /* exiting gettid */
+				exp_param = &exit_param[ptrace_stop / 2 - 1];
+				ASSERT_EQ(expected_exit_size, rc) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				ASSERT_EQ(PTRACE_SYSCALL_INFO_EXIT, info.op) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				ASSERT_TRUE(info.arch) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				ASSERT_TRUE(info.instruction_pointer) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				ASSERT_TRUE(info.stack_pointer) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				ASSERT_EQ(exp_param->is_error,
+					  info.exit.is_error) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				ASSERT_EQ(exp_param->rval, info.exit.rval) {
+					LOG_KILL_TRACEE("exit stop mismatch");
+				}
+				break;
+			default:
+				LOG_KILL_TRACEE("unexpected syscall stop");
+				abort();
+			}
+			break;
+
+		default:
+			LOG_KILL_TRACEE("unexpected stop signal %#x",
+					WSTOPSIG(status));
+			abort();
+		}
+
+		ASSERT_EQ(0, sys_ptrace(PTRACE_SYSCALL, pid, 0, 0)) {
+			LOG_KILL_TRACEE("PTRACE_SYSCALL: %m");
+		}
+	}
+
+	ASSERT_EQ(ARRAY_SIZE(args) * 2, ptrace_stop);
+}
+
+TEST_HARNESS_MAIN