From e244ae965b17280313d92baef71165efc00ac51b Mon Sep 17 00:00:00 2001

From: "Dmitry V. Levin" <ldv@altlinux.org>

Date: Sat, 4 Jul 2020 08:00:00 +0000

Subject: [PATCH 144/149] tests: check decoding of faccessat syscall in -P, -y,

 and -yy modes

* tests/faccessat.c: Rewrite.

* tests/faccessat-P.c: New file.

* tests/faccessat-y.c: Likewise.

* tests/faccessat-yy.c: Likewise.

* tests/faccessat.test: New test.

* tests/Makefile.am (DECODER_TESTS): Add faccessat.test.

* tests/gen_tests.in (faccessat): Remove.

(faccessat-P, faccessat-y, faccessat-yy): New entries.

* tests/pure_executables.list: Add faccessat-P, faccessat-y,

and faccessat-yy.

* tests/.gitignore: Likewise.

---

 tests/.gitignore            |   3 ++

 tests/Makefile.am           |   1 +

 tests/faccessat-P.c         |   4 ++

 tests/faccessat-y.c         |   4 ++

 tests/faccessat-yy.c        |   4 ++

 tests/faccessat.c           | 127 ++++++++++++++++++++++++++++++++++++++++++--

 tests/faccessat.test        |  19 +++++++

 tests/gen_tests.in          |   4 +-

 tests/pure_executables.list |   3 ++

 9 files changed, 163 insertions(+), 6 deletions(-)

 create mode 100644 tests/faccessat-P.c

 create mode 100644 tests/faccessat-y.c

 create mode 100644 tests/faccessat-yy.c

 create mode 100755 tests/faccessat.test

Index: strace-5.7/tests/Makefile.am

===================================================================

--- strace-5.7.orig/tests/Makefile.am	2021-08-24 19:42:16.041519983 +0200

+++ strace-5.7/tests/Makefile.am	2021-08-24 19:46:08.275554370 +0200

@@ -346,6 +346,7 @@

 	execve-v.test \

 	execve.test \

 	fadvise64.test \

+	faccessat.test \

 	futex.test \

 	getuid.test \

 	int_0x80.test \

Index: strace-5.7/tests/faccessat-P.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests/faccessat-P.c	2021-08-24 19:46:08.275554370 +0200

@@ -0,0 +1,4 @@

+#define PATH_TRACING

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests/faccessat-y.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests/faccessat-y.c	2021-08-24 19:46:08.276554362 +0200

@@ -0,0 +1,4 @@

+#define FD_PATH "</dev/full>"

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests/faccessat-yy.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests/faccessat-yy.c	2021-08-24 19:46:08.276554362 +0200

@@ -0,0 +1,4 @@

+#define FD_PATH "</dev/full<char 1:7>>"

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests/faccessat.c

===================================================================

--- strace-5.7.orig/tests/faccessat.c	2021-08-24 17:01:53.365934740 +0200

+++ strace-5.7/tests/faccessat.c	2021-08-24 19:46:08.277554353 +0200

@@ -1,4 +1,6 @@

 /*

+ * Check decoding of faccessat syscall.

+ *

  * Copyright (c) 2016-2019 The strace developers.

  * All rights reserved.

  *

@@ -10,18 +12,133 @@

 #ifdef __NR_faccessat

+# include <fcntl.h>

 # include <stdio.h>

 # include <unistd.h>

+# ifndef FD_PATH

+#  define FD_PATH ""

+# endif

+# ifndef SKIP_IF_PROC_IS_UNAVAILABLE

+#  define SKIP_IF_PROC_IS_UNAVAILABLE

+# endif

+

+static const char *errstr;

+

+static long

+k_faccessat(const unsigned int dirfd,

+	    const void *const pathname,

+	    const unsigned int mode)

+{

+	const kernel_ulong_t fill = (kernel_ulong_t) 0xdefaced00000000ULL;

+	const kernel_ulong_t bad = (kernel_ulong_t) 0xbadc0dedbadc0dedULL;

+

+	const kernel_ulong_t arg1 = fill | dirfd;

+	const kernel_ulong_t arg2 = (uintptr_t) pathname;

+	const kernel_ulong_t arg3 = fill | mode;

+	const long rc = syscall(__NR_faccessat,

+				arg1, arg2, arg3, bad, bad, bad);

+	errstr = sprintrc(rc);

+	return rc;

+}

+

 int

 main(void)

 {

-	static const char sample[] = "faccessat.sample";

-	const long int fd = (long int) 0xdeadbeefffffffffULL;

+	SKIP_IF_PROC_IS_UNAVAILABLE;

-	long rc = syscall(__NR_faccessat, fd, sample, F_OK);

-	printf("faccessat(%d, \"%s\", F_OK) = %ld %s (%m)\n",

-	       (int) fd, sample, rc, errno2name());

+	TAIL_ALLOC_OBJECT_CONST_PTR(const char, unterminated);

+	char *unterminated_str;

+	if (asprintf(&unterminated_str, "%p", unterminated) < 0)

+                perror_msg_and_fail("asprintf");

+	const void *const efault = unterminated + 1;

+	char *efault_str;

+	if (asprintf(&efault_str, "%p", efault) < 0)

+                perror_msg_and_fail("asprintf");

+

+	typedef struct {

+		char sym;

+		char null;

+	} sym_null;

+

+	TAIL_ALLOC_OBJECT_CONST_PTR(sym_null, dot);

+	dot->sym = '.';

+	dot->null = '\0';

+	const char *const null = &dot->null;

+

+	TAIL_ALLOC_OBJECT_CONST_PTR(sym_null, slash);

+	slash->sym = '/';

+	slash->null = '\0';

+

+	static const char path[] = "/dev/full";

+	const char *const fd_path = tail_memdup(path, sizeof(path));

+        int fd = open(path, O_WRONLY);

+        if (fd < 0)

+                perror_msg_and_fail("open: %s", path);

+	char *fd_str;

+	if (asprintf(&fd_str, "%d%s", fd, FD_PATH) < 0)

+                perror_msg_and_fail("asprintf");

+	char *path_quoted;

+	if (asprintf(&path_quoted, "\"%s\"", path) < 0)

+                perror_msg_and_fail("asprintf");

+

+	struct {

+		int val;

+		const char *str;

+	} dirfds[] = {

+		{ ARG_STR(-1) },

+		{ -100, "AT_FDCWD" },

+		{ fd, fd_str },

+	}, modes[] = {

+		{ ARG_STR(F_OK) },

+		{ ARG_STR(R_OK) },

+		{ ARG_STR(W_OK) },

+		{ ARG_STR(X_OK) },

+		{ ARG_STR(R_OK|W_OK) },

+		{ ARG_STR(R_OK|X_OK) },

+		{ ARG_STR(W_OK|X_OK) },

+		{ ARG_STR(R_OK|W_OK|X_OK) },

+		{ 8, "0x8 /* ?_OK */" },

+		{ -1, "R_OK|W_OK|X_OK|0xfffffff8" },

+	};

+

+	struct {

+		const void *val;

+		const char *str;

+	} paths[] = {

+		{ 0, "NULL" },

+		{ efault, efault_str },

+		{ unterminated, unterminated_str },

+		{ null, "\"\"" },

+		{ &dot->sym, "\".\"" },

+		{ &slash->sym, "\"/\"" },

+		{ fd_path, path_quoted },

+	};

+

+	for (unsigned int dirfd_i = 0;

+	     dirfd_i < ARRAY_SIZE(dirfds);

+	     ++dirfd_i) {

+		for (unsigned int path_i = 0;

+		     path_i < ARRAY_SIZE(paths);

+		     ++path_i) {

+			for (unsigned int mode_i = 0;

+			     mode_i < ARRAY_SIZE(modes);

+			     ++mode_i) {

+				k_faccessat(dirfds[dirfd_i].val,

+					    paths[path_i].val,

+					    modes[mode_i].val);

+# ifdef PATH_TRACING

+				if (dirfds[dirfd_i].val == fd ||

+				    paths[path_i].val == fd_path)

+# endif

+				printf("faccessat(%s, %s, %s) = %s\n",

+				       dirfds[dirfd_i].str,

+				       paths[path_i].str,

+				       modes[mode_i].str,

+				       errstr);

+			}

+		}

+	}

 	puts("+++ exited with 0 +++");

 	return 0;

Index: strace-5.7/tests/faccessat.test

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests/faccessat.test	2021-08-24 19:46:08.277554353 +0200

@@ -0,0 +1,19 @@

+#!/bin/sh

+#

+# Check decoding of faccessat syscall.

+#

+# Copyright (c) 2020 Dmitry V. Levin <ldv@altlinux.org>

+# All rights reserved.

+#

+# SPDX-License-Identifier: GPL-2.0-or-later

+

+. "${srcdir=.}/init.sh"

+

+check_prog sed

+

+run_prog > /dev/null

+run_strace -a23 --trace=faccessat "$@" $args > "$EXP"

+

+# Filter out faccessat() calls made by ld.so and libc.

+sed -n '/^faccessat(-1, NULL,/,$p' < "$LOG" > "$OUT"

+match_diff "$OUT" "$EXP"

Index: strace-5.7/tests/gen_tests.in

===================================================================

--- strace-5.7.orig/tests/gen_tests.in	2021-08-24 19:37:43.192829355 +0200

+++ strace-5.7/tests/gen_tests.in	2021-08-24 19:46:08.278554345 +0200

@@ -73,7 +73,9 @@

 erestartsys	-a34 -e signal=none -e trace=recvfrom

 execveat

 execveat-v	-v -e trace=execveat

-faccessat	-P $NAME.sample

+faccessat-P	-a23 --trace=faccessat -P /dev/full

+faccessat-y	+faccessat.test -a24 -y

+faccessat-yy	+faccessat.test -a24 -yy

 fadvise64_64	+fadvise64.test

 fallocate	-a18

 fanotify_init

Index: strace-5.7/tests/pure_executables.list

===================================================================

--- strace-5.7.orig/tests/pure_executables.list	2021-08-24 19:37:43.192829355 +0200

+++ strace-5.7/tests/pure_executables.list	2021-08-24 19:46:08.279554336 +0200

@@ -61,6 +61,9 @@

 execve

 execveat

 faccessat

+faccessat-P

+faccessat-y

+faccessat-yy

 fadvise64

 fadvise64_64

 fallocate

Index: strace-5.7/tests-m32/Makefile.am

===================================================================

--- strace-5.7.orig/tests-m32/Makefile.am	2021-08-24 19:42:16.045519949 +0200

+++ strace-5.7/tests-m32/Makefile.am	2021-08-24 19:46:08.279554336 +0200

@@ -346,6 +346,7 @@

 	execve-v.test \

 	execve.test \

 	fadvise64.test \

+	faccessat.test \

 	futex.test \

 	getuid.test \

 	int_0x80.test \

Index: strace-5.7/tests-m32/faccessat-P.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-m32/faccessat-P.c	2021-08-24 19:46:08.279554336 +0200

@@ -0,0 +1,4 @@

+#define PATH_TRACING

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests-m32/faccessat-y.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-m32/faccessat-y.c	2021-08-24 19:46:08.280554328 +0200

@@ -0,0 +1,4 @@

+#define FD_PATH "</dev/full>"

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests-m32/faccessat-yy.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-m32/faccessat-yy.c	2021-08-24 19:46:08.280554328 +0200

@@ -0,0 +1,4 @@

+#define FD_PATH "</dev/full<char 1:7>>"

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests-m32/faccessat.c

===================================================================

--- strace-5.7.orig/tests-m32/faccessat.c	2019-09-25 03:02:03.000000000 +0200

+++ strace-5.7/tests-m32/faccessat.c	2021-08-24 19:46:08.281554319 +0200

@@ -1,4 +1,6 @@

 /*

+ * Check decoding of faccessat syscall.

+ *

  * Copyright (c) 2016-2019 The strace developers.

  * All rights reserved.

  *

@@ -10,18 +12,133 @@

 #ifdef __NR_faccessat

+# include <fcntl.h>

 # include <stdio.h>

 # include <unistd.h>

+# ifndef FD_PATH

+#  define FD_PATH ""

+# endif

+# ifndef SKIP_IF_PROC_IS_UNAVAILABLE

+#  define SKIP_IF_PROC_IS_UNAVAILABLE

+# endif

+

+static const char *errstr;

+

+static long

+k_faccessat(const unsigned int dirfd,

+	    const void *const pathname,

+	    const unsigned int mode)

+{

+	const kernel_ulong_t fill = (kernel_ulong_t) 0xdefaced00000000ULL;

+	const kernel_ulong_t bad = (kernel_ulong_t) 0xbadc0dedbadc0dedULL;

+

+	const kernel_ulong_t arg1 = fill | dirfd;

+	const kernel_ulong_t arg2 = (uintptr_t) pathname;

+	const kernel_ulong_t arg3 = fill | mode;

+	const long rc = syscall(__NR_faccessat,

+				arg1, arg2, arg3, bad, bad, bad);

+	errstr = sprintrc(rc);

+	return rc;

+}

+

 int

 main(void)

 {

-	static const char sample[] = "faccessat.sample";

-	const long int fd = (long int) 0xdeadbeefffffffffULL;

+	SKIP_IF_PROC_IS_UNAVAILABLE;

-	long rc = syscall(__NR_faccessat, fd, sample, F_OK);

-	printf("faccessat(%d, \"%s\", F_OK) = %ld %s (%m)\n",

-	       (int) fd, sample, rc, errno2name());

+	TAIL_ALLOC_OBJECT_CONST_PTR(const char, unterminated);

+	char *unterminated_str;

+	if (asprintf(&unterminated_str, "%p", unterminated) < 0)

+                perror_msg_and_fail("asprintf");

+	const void *const efault = unterminated + 1;

+	char *efault_str;

+	if (asprintf(&efault_str, "%p", efault) < 0)

+                perror_msg_and_fail("asprintf");

+

+	typedef struct {

+		char sym;

+		char null;

+	} sym_null;

+

+	TAIL_ALLOC_OBJECT_CONST_PTR(sym_null, dot);

+	dot->sym = '.';

+	dot->null = '\0';

+	const char *const null = &dot->null;

+

+	TAIL_ALLOC_OBJECT_CONST_PTR(sym_null, slash);

+	slash->sym = '/';

+	slash->null = '\0';

+

+	static const char path[] = "/dev/full";

+	const char *const fd_path = tail_memdup(path, sizeof(path));

+        int fd = open(path, O_WRONLY);

+        if (fd < 0)

+                perror_msg_and_fail("open: %s", path);

+	char *fd_str;

+	if (asprintf(&fd_str, "%d%s", fd, FD_PATH) < 0)

+                perror_msg_and_fail("asprintf");

+	char *path_quoted;

+	if (asprintf(&path_quoted, "\"%s\"", path) < 0)

+                perror_msg_and_fail("asprintf");

+

+	struct {

+		int val;

+		const char *str;

+	} dirfds[] = {

+		{ ARG_STR(-1) },

+		{ -100, "AT_FDCWD" },

+		{ fd, fd_str },

+	}, modes[] = {

+		{ ARG_STR(F_OK) },

+		{ ARG_STR(R_OK) },

+		{ ARG_STR(W_OK) },

+		{ ARG_STR(X_OK) },

+		{ ARG_STR(R_OK|W_OK) },

+		{ ARG_STR(R_OK|X_OK) },

+		{ ARG_STR(W_OK|X_OK) },

+		{ ARG_STR(R_OK|W_OK|X_OK) },

+		{ 8, "0x8 /* ?_OK */" },

+		{ -1, "R_OK|W_OK|X_OK|0xfffffff8" },

+	};

+

+	struct {

+		const void *val;

+		const char *str;

+	} paths[] = {

+		{ 0, "NULL" },

+		{ efault, efault_str },

+		{ unterminated, unterminated_str },

+		{ null, "\"\"" },

+		{ &dot->sym, "\".\"" },

+		{ &slash->sym, "\"/\"" },

+		{ fd_path, path_quoted },

+	};

+

+	for (unsigned int dirfd_i = 0;

+	     dirfd_i < ARRAY_SIZE(dirfds);

+	     ++dirfd_i) {

+		for (unsigned int path_i = 0;

+		     path_i < ARRAY_SIZE(paths);

+		     ++path_i) {

+			for (unsigned int mode_i = 0;

+			     mode_i < ARRAY_SIZE(modes);

+			     ++mode_i) {

+				k_faccessat(dirfds[dirfd_i].val,

+					    paths[path_i].val,

+					    modes[mode_i].val);

+# ifdef PATH_TRACING

+				if (dirfds[dirfd_i].val == fd ||

+				    paths[path_i].val == fd_path)

+# endif

+				printf("faccessat(%s, %s, %s) = %s\n",

+				       dirfds[dirfd_i].str,

+				       paths[path_i].str,

+				       modes[mode_i].str,

+				       errstr);

+			}

+		}

+	}

 	puts("+++ exited with 0 +++");

 	return 0;

Index: strace-5.7/tests-m32/faccessat.test

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-m32/faccessat.test	2021-08-24 19:46:08.281554319 +0200

@@ -0,0 +1,19 @@

+#!/bin/sh

+#

+# Check decoding of faccessat syscall.

+#

+# Copyright (c) 2020 Dmitry V. Levin <ldv@altlinux.org>

+# All rights reserved.

+#

+# SPDX-License-Identifier: GPL-2.0-or-later

+

+. "${srcdir=.}/init.sh"

+

+check_prog sed

+

+run_prog > /dev/null

+run_strace -a23 --trace=faccessat "$@" $args > "$EXP"

+

+# Filter out faccessat() calls made by ld.so and libc.

+sed -n '/^faccessat(-1, NULL,/,$p' < "$LOG" > "$OUT"

+match_diff "$OUT" "$EXP"

Index: strace-5.7/tests-m32/gen_tests.in

===================================================================

--- strace-5.7.orig/tests-m32/gen_tests.in	2021-08-24 19:37:43.193829347 +0200

+++ strace-5.7/tests-m32/gen_tests.in	2021-08-24 19:46:08.282554311 +0200

@@ -73,7 +73,9 @@

 erestartsys	-a34 -e signal=none -e trace=recvfrom

 execveat

 execveat-v	-v -e trace=execveat

-faccessat	-P $NAME.sample

+faccessat-P	-a23 --trace=faccessat -P /dev/full

+faccessat-y	+faccessat.test -a24 -y

+faccessat-yy	+faccessat.test -a24 -yy

 fadvise64_64	+fadvise64.test

 fallocate	-a18

 fanotify_init

Index: strace-5.7/tests-m32/pure_executables.list

===================================================================

--- strace-5.7.orig/tests-m32/pure_executables.list	2021-08-24 19:37:43.193829347 +0200

+++ strace-5.7/tests-m32/pure_executables.list	2021-08-24 19:46:08.283554302 +0200

@@ -61,6 +61,9 @@

 execve

 execveat

 faccessat

+faccessat-P

+faccessat-y

+faccessat-yy

 fadvise64

 fadvise64_64

 fallocate

Index: strace-5.7/tests-mx32/Makefile.am

===================================================================

--- strace-5.7.orig/tests-mx32/Makefile.am	2021-08-24 19:42:16.048519924 +0200

+++ strace-5.7/tests-mx32/Makefile.am	2021-08-24 19:46:08.283554302 +0200

@@ -346,6 +346,7 @@

 	execve-v.test \

 	execve.test \

 	fadvise64.test \

+	faccessat.test \

 	futex.test \

 	getuid.test \

 	int_0x80.test \

Index: strace-5.7/tests-mx32/faccessat-P.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-mx32/faccessat-P.c	2021-08-24 19:46:08.283554302 +0200

@@ -0,0 +1,4 @@

+#define PATH_TRACING

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests-mx32/faccessat-y.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-mx32/faccessat-y.c	2021-08-24 19:46:08.284554294 +0200

@@ -0,0 +1,4 @@

+#define FD_PATH "</dev/full>"

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests-mx32/faccessat-yy.c

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-mx32/faccessat-yy.c	2021-08-24 19:46:08.284554294 +0200

@@ -0,0 +1,4 @@

+#define FD_PATH "</dev/full<char 1:7>>"

+#define SKIP_IF_PROC_IS_UNAVAILABLE skip_if_unavailable("/proc/self/fd/")

+

+#include "faccessat.c"

Index: strace-5.7/tests-mx32/faccessat.c

===================================================================

--- strace-5.7.orig/tests-mx32/faccessat.c	2019-09-25 03:02:03.000000000 +0200

+++ strace-5.7/tests-mx32/faccessat.c	2021-08-24 19:46:08.285554285 +0200

@@ -1,4 +1,6 @@

 /*

+ * Check decoding of faccessat syscall.

+ *

  * Copyright (c) 2016-2019 The strace developers.

  * All rights reserved.

  *

@@ -10,18 +12,133 @@

 #ifdef __NR_faccessat

+# include <fcntl.h>

 # include <stdio.h>

 # include <unistd.h>

+# ifndef FD_PATH

+#  define FD_PATH ""

+# endif

+# ifndef SKIP_IF_PROC_IS_UNAVAILABLE

+#  define SKIP_IF_PROC_IS_UNAVAILABLE

+# endif

+

+static const char *errstr;

+

+static long

+k_faccessat(const unsigned int dirfd,

+	    const void *const pathname,

+	    const unsigned int mode)

+{

+	const kernel_ulong_t fill = (kernel_ulong_t) 0xdefaced00000000ULL;

+	const kernel_ulong_t bad = (kernel_ulong_t) 0xbadc0dedbadc0dedULL;

+

+	const kernel_ulong_t arg1 = fill | dirfd;

+	const kernel_ulong_t arg2 = (uintptr_t) pathname;

+	const kernel_ulong_t arg3 = fill | mode;

+	const long rc = syscall(__NR_faccessat,

+				arg1, arg2, arg3, bad, bad, bad);

+	errstr = sprintrc(rc);

+	return rc;

+}

+

 int

 main(void)

 {

-	static const char sample[] = "faccessat.sample";

-	const long int fd = (long int) 0xdeadbeefffffffffULL;

+	SKIP_IF_PROC_IS_UNAVAILABLE;

-	long rc = syscall(__NR_faccessat, fd, sample, F_OK);

-	printf("faccessat(%d, \"%s\", F_OK) = %ld %s (%m)\n",

-	       (int) fd, sample, rc, errno2name());

+	TAIL_ALLOC_OBJECT_CONST_PTR(const char, unterminated);

+	char *unterminated_str;

+	if (asprintf(&unterminated_str, "%p", unterminated) < 0)

+                perror_msg_and_fail("asprintf");

+	const void *const efault = unterminated + 1;

+	char *efault_str;

+	if (asprintf(&efault_str, "%p", efault) < 0)

+                perror_msg_and_fail("asprintf");

+

+	typedef struct {

+		char sym;

+		char null;

+	} sym_null;

+

+	TAIL_ALLOC_OBJECT_CONST_PTR(sym_null, dot);

+	dot->sym = '.';

+	dot->null = '\0';

+	const char *const null = &dot->null;

+

+	TAIL_ALLOC_OBJECT_CONST_PTR(sym_null, slash);

+	slash->sym = '/';

+	slash->null = '\0';

+

+	static const char path[] = "/dev/full";

+	const char *const fd_path = tail_memdup(path, sizeof(path));

+        int fd = open(path, O_WRONLY);

+        if (fd < 0)

+                perror_msg_and_fail("open: %s", path);

+	char *fd_str;

+	if (asprintf(&fd_str, "%d%s", fd, FD_PATH) < 0)

+                perror_msg_and_fail("asprintf");

+	char *path_quoted;

+	if (asprintf(&path_quoted, "\"%s\"", path) < 0)

+                perror_msg_and_fail("asprintf");

+

+	struct {

+		int val;

+		const char *str;

+	} dirfds[] = {

+		{ ARG_STR(-1) },

+		{ -100, "AT_FDCWD" },

+		{ fd, fd_str },

+	}, modes[] = {

+		{ ARG_STR(F_OK) },

+		{ ARG_STR(R_OK) },

+		{ ARG_STR(W_OK) },

+		{ ARG_STR(X_OK) },

+		{ ARG_STR(R_OK|W_OK) },

+		{ ARG_STR(R_OK|X_OK) },

+		{ ARG_STR(W_OK|X_OK) },

+		{ ARG_STR(R_OK|W_OK|X_OK) },

+		{ 8, "0x8 /* ?_OK */" },

+		{ -1, "R_OK|W_OK|X_OK|0xfffffff8" },

+	};

+

+	struct {

+		const void *val;

+		const char *str;

+	} paths[] = {

+		{ 0, "NULL" },

+		{ efault, efault_str },

+		{ unterminated, unterminated_str },

+		{ null, "\"\"" },

+		{ &dot->sym, "\".\"" },

+		{ &slash->sym, "\"/\"" },

+		{ fd_path, path_quoted },

+	};

+

+	for (unsigned int dirfd_i = 0;

+	     dirfd_i < ARRAY_SIZE(dirfds);

+	     ++dirfd_i) {

+		for (unsigned int path_i = 0;

+		     path_i < ARRAY_SIZE(paths);

+		     ++path_i) {

+			for (unsigned int mode_i = 0;

+			     mode_i < ARRAY_SIZE(modes);

+			     ++mode_i) {

+				k_faccessat(dirfds[dirfd_i].val,

+					    paths[path_i].val,

+					    modes[mode_i].val);

+# ifdef PATH_TRACING

+				if (dirfds[dirfd_i].val == fd ||

+				    paths[path_i].val == fd_path)

+# endif

+				printf("faccessat(%s, %s, %s) = %s\n",

+				       dirfds[dirfd_i].str,

+				       paths[path_i].str,

+				       modes[mode_i].str,

+				       errstr);

+			}

+		}

+	}

 	puts("+++ exited with 0 +++");

 	return 0;

Index: strace-5.7/tests-mx32/faccessat.test

===================================================================

--- /dev/null	1970-01-01 00:00:00.000000000 +0000

+++ strace-5.7/tests-mx32/faccessat.test	2021-08-24 19:46:08.285554285 +0200

@@ -0,0 +1,19 @@

+#!/bin/sh

+#

+# Check decoding of faccessat syscall.

+#

+# Copyright (c) 2020 Dmitry V. Levin <ldv@altlinux.org>

+# All rights reserved.

+#

+# SPDX-License-Identifier: GPL-2.0-or-later