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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /tools/testing/selftests/exec
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'tools/testing/selftests/exec')
-rw-r--r--tools/testing/selftests/exec/.gitignore21
-rw-r--r--tools/testing/selftests/exec/Makefile57
-rwxr-xr-xtools/testing/selftests/exec/binfmt_script.py179
-rwxr-xr-xtools/testing/selftests/exec/check-exec-tests.sh205
-rw-r--r--tools/testing/selftests/exec/check-exec.c463
-rw-r--r--tools/testing/selftests/exec/config2
-rw-r--r--tools/testing/selftests/exec/execveat.c520
-rw-r--r--tools/testing/selftests/exec/false.c5
-rw-r--r--tools/testing/selftests/exec/load_address.c105
-rw-r--r--tools/testing/selftests/exec/non-regular.c196
-rw-r--r--tools/testing/selftests/exec/null-argv.c78
-rw-r--r--tools/testing/selftests/exec/recursion-depth.c66
12 files changed, 1897 insertions, 0 deletions
diff --git a/tools/testing/selftests/exec/.gitignore b/tools/testing/selftests/exec/.gitignore
new file mode 100644
index 000000000..7f3d1ae76
--- /dev/null
+++ b/tools/testing/selftests/exec/.gitignore
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+subdir*
+script*
+execveat
+execveat.symlink
+execveat.moved
+execveat.path.ephemeral
+execveat.ephemeral
+execveat.denatured
+non-regular
+null-argv
+/check-exec
+/false
+/inc
+/load_address.*
+!load_address.c
+/recursion-depth
+/set-exec
+xxxxxxxx*
+pipe
+S_I*.test
diff --git a/tools/testing/selftests/exec/Makefile b/tools/testing/selftests/exec/Makefile
new file mode 100644
index 000000000..45a3cfc43
--- /dev/null
+++ b/tools/testing/selftests/exec/Makefile
@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS = -Wall
+CFLAGS += -Wno-nonnull
+CFLAGS += $(KHDR_INCLUDES)
+
+LDLIBS += -lcap
+
+ALIGNS := 0x1000 0x200000 0x1000000
+ALIGN_PIES := $(patsubst %,load_address.%,$(ALIGNS))
+ALIGN_STATIC_PIES := $(patsubst %,load_address.static.%,$(ALIGNS))
+ALIGNMENT_TESTS := $(ALIGN_PIES) $(ALIGN_STATIC_PIES)
+
+TEST_PROGS := binfmt_script.py check-exec-tests.sh
+TEST_GEN_PROGS := execveat non-regular $(ALIGNMENT_TESTS)
+TEST_GEN_PROGS_EXTENDED := false inc set-exec script-exec.inc script-noexec.inc
+TEST_GEN_FILES := execveat.symlink execveat.denatured script subdir
+# Makefile is a run-time dependency, since it's accessed by the execveat test
+TEST_FILES := Makefile
+
+TEST_GEN_PROGS += recursion-depth
+TEST_GEN_PROGS += null-argv
+TEST_GEN_PROGS += check-exec
+
+EXTRA_CLEAN := $(OUTPUT)/subdir.moved $(OUTPUT)/execveat.moved $(OUTPUT)/xxxxx* \
+ $(OUTPUT)/S_I*.test
+
+include ../lib.mk
+
+CHECK_EXEC_SAMPLES := $(top_srcdir)/samples/check-exec
+
+$(OUTPUT)/subdir:
+ mkdir -p $@
+$(OUTPUT)/script: Makefile
+ echo '#!/bin/bash' > $@
+ echo 'exit $$*' >> $@
+ chmod +x $@
+$(OUTPUT)/execveat.symlink: $(OUTPUT)/execveat
+ cd $(OUTPUT) && ln -s -f $(shell basename $<) $(shell basename $@)
+$(OUTPUT)/execveat.denatured: $(OUTPUT)/execveat
+ cp $< $@
+ chmod -x $@
+$(OUTPUT)/load_address.0x%: load_address.c
+ $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=$(lastword $(subst ., ,$@)) \
+ -fPIE -pie $< -o $@
+$(OUTPUT)/load_address.static.0x%: load_address.c
+ $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=$(lastword $(subst ., ,$@)) \
+ -fPIE -static-pie $< -o $@
+$(OUTPUT)/false: false.c
+ $(CC) $(CFLAGS) $(LDFLAGS) -static $< -o $@
+$(OUTPUT)/inc: $(CHECK_EXEC_SAMPLES)/inc.c
+ $(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+$(OUTPUT)/set-exec: $(CHECK_EXEC_SAMPLES)/set-exec.c
+ $(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+$(OUTPUT)/script-exec.inc: $(CHECK_EXEC_SAMPLES)/script-exec.inc
+ cp $< $@
+$(OUTPUT)/script-noexec.inc: $(CHECK_EXEC_SAMPLES)/script-noexec.inc
+ cp $< $@
diff --git a/tools/testing/selftests/exec/binfmt_script.py b/tools/testing/selftests/exec/binfmt_script.py
new file mode 100755
index 000000000..2c575a2c0
--- /dev/null
+++ b/tools/testing/selftests/exec/binfmt_script.py
@@ -0,0 +1,179 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test that truncation of bprm->buf doesn't cause unexpected execs paths, along
+# with various other pathological cases.
+import os, subprocess
+
+# Relevant commits
+#
+# b5372fe5dc84 ("exec: load_script: Do not exec truncated interpreter path")
+# 6eb3c3d0a52d ("exec: increase BINPRM_BUF_SIZE to 256")
+
+# BINPRM_BUF_SIZE
+SIZE=256
+
+NAME_MAX=int(subprocess.check_output(["getconf", "NAME_MAX", "."]))
+
+test_num=0
+pass_num=0
+fail_num=0
+
+code='''#!/usr/bin/perl
+print "Executed interpreter! Args:\n";
+print "0 : '$0'\n";
+$counter = 1;
+foreach my $a (@ARGV) {
+ print "$counter : '$a'\n";
+ $counter++;
+}
+'''
+
+##
+# test - produce a binfmt_script hashbang line for testing
+#
+# @size: bytes for bprm->buf line, including hashbang but not newline
+# @good: whether this script is expected to execute correctly
+# @hashbang: the special 2 bytes for running binfmt_script
+# @leading: any leading whitespace before the executable path
+# @root: start of executable pathname
+# @target: end of executable pathname
+# @arg: bytes following the executable pathname
+# @fill: character to fill between @root and @target to reach @size bytes
+# @newline: character to use as newline, not counted towards @size
+# ...
+def test(name, size, good=True, leading="", root="./", target="/perl",
+ fill="A", arg="", newline="\n", hashbang="#!"):
+ global test_num, pass_num, fail_num, tests, NAME_MAX
+ test_num += 1
+ if test_num > tests:
+ raise ValueError("more binfmt_script tests than expected! (want %d, expected %d)"
+ % (test_num, tests))
+
+ middle = ""
+ remaining = size - len(hashbang) - len(leading) - len(root) - len(target) - len(arg)
+ # The middle of the pathname must not exceed NAME_MAX
+ while remaining >= NAME_MAX:
+ middle += fill * (NAME_MAX - 1)
+ middle += '/'
+ remaining -= NAME_MAX
+ middle += fill * remaining
+
+ dirpath = root + middle
+ binary = dirpath + target
+ if len(target):
+ os.makedirs(dirpath, mode=0o755, exist_ok=True)
+ open(binary, "w").write(code)
+ os.chmod(binary, 0o755)
+
+ buf=hashbang + leading + root + middle + target + arg + newline
+ if len(newline) > 0:
+ buf += 'echo this is not really perl\n'
+
+ script = "binfmt_script-%s" % (name)
+ open(script, "w").write(buf)
+ os.chmod(script, 0o755)
+
+ proc = subprocess.Popen(["./%s" % (script)], shell=True,
+ stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+ stdout = proc.communicate()[0]
+
+ if proc.returncode == 0 and b'Executed interpreter' in stdout:
+ if good:
+ print("ok %d - binfmt_script %s (successful good exec)"
+ % (test_num, name))
+ pass_num += 1
+ else:
+ print("not ok %d - binfmt_script %s succeeded when it should have failed"
+ % (test_num, name))
+ fail_num = 1
+ else:
+ if good:
+ print("not ok %d - binfmt_script %s failed when it should have succeeded (rc:%d)"
+ % (test_num, name, proc.returncode))
+ fail_num = 1
+ else:
+ print("ok %d - binfmt_script %s (correctly failed bad exec)"
+ % (test_num, name))
+ pass_num += 1
+
+ # Clean up crazy binaries
+ os.unlink(script)
+ if len(target):
+ elements = binary.split('/')
+ os.unlink(binary)
+ elements.pop()
+ while len(elements) > 1:
+ os.rmdir("/".join(elements))
+ elements.pop()
+
+tests=27
+print("TAP version 1.3")
+print("1..%d" % (tests))
+
+### FAIL (8 tests)
+
+# Entire path is well past the BINFMT_BUF_SIZE.
+test(name="too-big", size=SIZE+80, good=False)
+# Path is right at max size, making it impossible to tell if it was truncated.
+test(name="exact", size=SIZE, good=False)
+# Same as above, but with leading whitespace.
+test(name="exact-space", size=SIZE, good=False, leading=" ")
+# Huge buffer of only whitespace.
+test(name="whitespace-too-big", size=SIZE+71, good=False, root="",
+ fill=" ", target="")
+# A good path, but it gets truncated due to leading whitespace.
+test(name="truncated", size=SIZE+17, good=False, leading=" " * 19)
+# Entirely empty except for #!
+test(name="empty", size=2, good=False, root="",
+ fill="", target="", newline="")
+# Within size, but entirely spaces
+test(name="spaces", size=SIZE-1, good=False, root="", fill=" ",
+ target="", newline="")
+# Newline before binary.
+test(name="newline-prefix", size=SIZE-1, good=False, leading="\n",
+ root="", fill=" ", target="")
+
+### ok (19 tests)
+
+# The original test case that was broken by commit:
+# 8099b047ecc4 ("exec: load_script: don't blindly truncate shebang string")
+test(name="test.pl", size=439, leading=" ",
+ root="./nix/store/bwav8kz8b3y471wjsybgzw84mrh4js9-perl-5.28.1/bin",
+ arg=" -I/nix/store/x6yyav38jgr924nkna62q3pkp0dgmzlx-perl5.28.1-File-Slurp-9999.25/lib/perl5/site_perl -I/nix/store/ha8v67sl8dac92r9z07vzr4gv1y9nwqz-perl5.28.1-Net-DBus-1.1.0/lib/perl5/site_perl -I/nix/store/dcrkvnjmwh69ljsvpbdjjdnqgwx90a9d-perl5.28.1-XML-Parser-2.44/lib/perl5/site_perl -I/nix/store/rmji88k2zz7h4zg97385bygcydrf2q8h-perl5.28.1-XML-Twig-3.52/lib/perl5/site_perl")
+# One byte under size, leaving newline visible.
+test(name="one-under", size=SIZE-1)
+# Two bytes under size, leaving newline visible.
+test(name="two-under", size=SIZE-2)
+# Exact size, but trailing whitespace visible instead of newline
+test(name="exact-trunc-whitespace", size=SIZE, arg=" ")
+# Exact size, but trailing space and first arg char visible instead of newline.
+test(name="exact-trunc-arg", size=SIZE, arg=" f")
+# One bute under, with confirmed non-truncated arg since newline now visible.
+test(name="one-under-full-arg", size=SIZE-1, arg=" f")
+# Short read buffer by one byte.
+test(name="one-under-no-nl", size=SIZE-1, newline="")
+# Short read buffer by half buffer size.
+test(name="half-under-no-nl", size=int(SIZE/2), newline="")
+# One byte under with whitespace arg. leaving wenline visible.
+test(name="one-under-trunc-arg", size=SIZE-1, arg=" ")
+# One byte under with whitespace leading. leaving wenline visible.
+test(name="one-under-leading", size=SIZE-1, leading=" ")
+# One byte under with whitespace leading and as arg. leaving newline visible.
+test(name="one-under-leading-trunc-arg", size=SIZE-1, leading=" ", arg=" ")
+# Same as above, but with 2 bytes under
+test(name="two-under-no-nl", size=SIZE-2, newline="")
+test(name="two-under-trunc-arg", size=SIZE-2, arg=" ")
+test(name="two-under-leading", size=SIZE-2, leading=" ")
+test(name="two-under-leading-trunc-arg", size=SIZE-2, leading=" ", arg=" ")
+# Same as above, but with buffer half filled
+test(name="two-under-no-nl", size=int(SIZE/2), newline="")
+test(name="two-under-trunc-arg", size=int(SIZE/2), arg=" ")
+test(name="two-under-leading", size=int(SIZE/2), leading=" ")
+test(name="two-under-lead-trunc-arg", size=int(SIZE/2), leading=" ", arg=" ")
+
+print("# Totals: pass:%d fail:%d xfail:0 xpass:0 skip:0 error:0" % (pass_num, fail_num))
+
+if test_num != tests:
+ raise ValueError("fewer binfmt_script tests than expected! (ran %d, expected %d"
+ % (test_num, tests))
diff --git a/tools/testing/selftests/exec/check-exec-tests.sh b/tools/testing/selftests/exec/check-exec-tests.sh
new file mode 100755
index 000000000..87102906a
--- /dev/null
+++ b/tools/testing/selftests/exec/check-exec-tests.sh
@@ -0,0 +1,205 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Test the "inc" interpreter.
+#
+# See include/uapi/linux/securebits.h, include/uapi/linux/fcntl.h and
+# samples/check-exec/inc.c
+#
+# Copyright © 2024 Microsoft Corporation
+
+set -u -e -o pipefail
+
+EXPECTED_OUTPUT="1"
+exec 2>/dev/null
+
+DIR="$(dirname $(readlink -f "$0"))"
+source "${DIR}"/../kselftest/ktap_helpers.sh
+
+exec_direct() {
+ local expect="$1"
+ local script="$2"
+ shift 2
+ local ret=0
+ local out
+
+ # Updates PATH for `env` to execute the `inc` interpreter.
+ out="$(PATH="." "$@" "${script}")" || ret=$?
+
+ if [[ ${ret} -ne ${expect} ]]; then
+ echo "ERROR: Wrong expectation for direct file execution: ${ret}"
+ return 1
+ fi
+ if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then
+ echo "ERROR: Wrong output for direct file execution: ${out}"
+ return 1
+ fi
+}
+
+exec_indirect() {
+ local expect="$1"
+ local script="$2"
+ shift 2
+ local ret=0
+ local out
+
+ # Script passed as argument.
+ out="$("$@" ./inc "${script}")" || ret=$?
+
+ if [[ ${ret} -ne ${expect} ]]; then
+ echo "ERROR: Wrong expectation for indirect file execution: ${ret}"
+ return 1
+ fi
+ if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then
+ echo "ERROR: Wrong output for indirect file execution: ${out}"
+ return 1
+ fi
+}
+
+exec_stdin_reg() {
+ local expect="$1"
+ local script="$2"
+ shift 2
+ local ret=0
+ local out
+
+ # Executing stdin must be allowed if the related file is executable.
+ out="$("$@" ./inc -i < "${script}")" || ret=$?
+
+ if [[ ${ret} -ne ${expect} ]]; then
+ echo "ERROR: Wrong expectation for stdin regular file execution: ${ret}"
+ return 1
+ fi
+ if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then
+ echo "ERROR: Wrong output for stdin regular file execution: ${out}"
+ return 1
+ fi
+}
+
+exec_stdin_pipe() {
+ local expect="$1"
+ shift
+ local ret=0
+ local out
+
+ # A pipe is not executable.
+ out="$(cat script-exec.inc | "$@" ./inc -i)" || ret=$?
+
+ if [[ ${ret} -ne ${expect} ]]; then
+ echo "ERROR: Wrong expectation for stdin pipe execution: ${ret}"
+ return 1
+ fi
+}
+
+exec_argument() {
+ local expect="$1"
+ local ret=0
+ shift
+ local out
+
+ # Script not coming from a file must not be executed.
+ out="$("$@" ./inc -c "$(< script-exec.inc)")" || ret=$?
+
+ if [[ ${ret} -ne ${expect} ]]; then
+ echo "ERROR: Wrong expectation for arbitrary argument execution: ${ret}"
+ return 1
+ fi
+ if [[ ${ret} -eq 0 && "${out}" != "${EXPECTED_OUTPUT}" ]]; then
+ echo "ERROR: Wrong output for arbitrary argument execution: ${out}"
+ return 1
+ fi
+}
+
+exec_interactive() {
+ exec_stdin_pipe "$@"
+ exec_argument "$@"
+}
+
+ktap_test() {
+ ktap_test_result "$*" "$@"
+}
+
+ktap_print_header
+ktap_set_plan 28
+
+# Without secbit configuration, nothing is changed.
+
+ktap_print_msg "By default, executable scripts are allowed to be interpreted and executed."
+ktap_test exec_direct 0 script-exec.inc
+ktap_test exec_indirect 0 script-exec.inc
+
+ktap_print_msg "By default, executable stdin is allowed to be interpreted."
+ktap_test exec_stdin_reg 0 script-exec.inc
+
+ktap_print_msg "By default, non-executable scripts are allowed to be interpreted, but not directly executed."
+# We get 126 because of direct execution by Bash.
+ktap_test exec_direct 126 script-noexec.inc
+ktap_test exec_indirect 0 script-noexec.inc
+
+ktap_print_msg "By default, non-executable stdin is allowed to be interpreted."
+ktap_test exec_stdin_reg 0 script-noexec.inc
+
+ktap_print_msg "By default, interactive commands are allowed to be interpreted."
+ktap_test exec_interactive 0
+
+# With only file restriction: protect non-malicious users from inadvertent errors (e.g. python ~/Downloads/*.py).
+
+ktap_print_msg "With -f, executable scripts are allowed to be interpreted and executed."
+ktap_test exec_direct 0 script-exec.inc ./set-exec -f --
+ktap_test exec_indirect 0 script-exec.inc ./set-exec -f --
+
+ktap_print_msg "With -f, executable stdin is allowed to be interpreted."
+ktap_test exec_stdin_reg 0 script-exec.inc ./set-exec -f --
+
+ktap_print_msg "With -f, non-executable scripts are not allowed to be executed nor interpreted."
+# Direct execution of non-executable script is alwayse denied by the kernel.
+ktap_test exec_direct 1 script-noexec.inc ./set-exec -f --
+ktap_test exec_indirect 1 script-noexec.inc ./set-exec -f --
+
+ktap_print_msg "With -f, non-executable stdin is allowed to be interpreted."
+ktap_test exec_stdin_reg 0 script-noexec.inc ./set-exec -f --
+
+ktap_print_msg "With -f, interactive commands are allowed to be interpreted."
+ktap_test exec_interactive 0 ./set-exec -f --
+
+# With only denied interactive commands: check or monitor script content (e.g. with LSM).
+
+ktap_print_msg "With -i, executable scripts are allowed to be interpreted and executed."
+ktap_test exec_direct 0 script-exec.inc ./set-exec -i --
+ktap_test exec_indirect 0 script-exec.inc ./set-exec -i --
+
+ktap_print_msg "With -i, executable stdin is allowed to be interpreted."
+ktap_test exec_stdin_reg 0 script-exec.inc ./set-exec -i --
+
+ktap_print_msg "With -i, non-executable scripts are allowed to be interpreted, but not directly executed."
+# Direct execution of non-executable script is alwayse denied by the kernel.
+ktap_test exec_direct 1 script-noexec.inc ./set-exec -i --
+ktap_test exec_indirect 0 script-noexec.inc ./set-exec -i --
+
+ktap_print_msg "With -i, non-executable stdin is not allowed to be interpreted."
+ktap_test exec_stdin_reg 1 script-noexec.inc ./set-exec -i --
+
+ktap_print_msg "With -i, interactive commands are not allowed to be interpreted."
+ktap_test exec_interactive 1 ./set-exec -i --
+
+# With both file restriction and denied interactive commands: only allow executable scripts.
+
+ktap_print_msg "With -fi, executable scripts are allowed to be interpreted and executed."
+ktap_test exec_direct 0 script-exec.inc ./set-exec -fi --
+ktap_test exec_indirect 0 script-exec.inc ./set-exec -fi --
+
+ktap_print_msg "With -fi, executable stdin is allowed to be interpreted."
+ktap_test exec_stdin_reg 0 script-exec.inc ./set-exec -fi --
+
+ktap_print_msg "With -fi, non-executable scripts are not allowed to be interpreted nor executed."
+# Direct execution of non-executable script is alwayse denied by the kernel.
+ktap_test exec_direct 1 script-noexec.inc ./set-exec -fi --
+ktap_test exec_indirect 1 script-noexec.inc ./set-exec -fi --
+
+ktap_print_msg "With -fi, non-executable stdin is not allowed to be interpreted."
+ktap_test exec_stdin_reg 1 script-noexec.inc ./set-exec -fi --
+
+ktap_print_msg "With -fi, interactive commands are not allowed to be interpreted."
+ktap_test exec_interactive 1 ./set-exec -fi --
+
+ktap_finished
diff --git a/tools/testing/selftests/exec/check-exec.c b/tools/testing/selftests/exec/check-exec.c
new file mode 100644
index 000000000..f2397e75a
--- /dev/null
+++ b/tools/testing/selftests/exec/check-exec.c
@@ -0,0 +1,463 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test execveat(2) with AT_EXECVE_CHECK, and prctl(2) with
+ * SECBIT_EXEC_RESTRICT_FILE, SECBIT_EXEC_DENY_INTERACTIVE, and their locked
+ * counterparts.
+ *
+ * Copyright © 2018-2020 ANSSI
+ * Copyright © 2024 Microsoft Corporation
+ *
+ * Author: Mickaël Salaün <mic@digikod.net>
+ */
+
+#include <asm-generic/unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/prctl.h>
+#include <linux/securebits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/capability.h>
+#include <sys/mount.h>
+#include <sys/prctl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/sysmacros.h>
+#include <unistd.h>
+
+/* Defines AT_EXECVE_CHECK without type conflicts. */
+#define _ASM_GENERIC_FCNTL_H
+#include <linux/fcntl.h>
+
+#include "kselftest_harness.h"
+
+static int sys_execveat(int dirfd, const char *pathname, char *const argv[],
+ char *const envp[], int flags)
+{
+ return syscall(__NR_execveat, dirfd, pathname, argv, envp, flags);
+}
+
+static void drop_privileges(struct __test_metadata *const _metadata)
+{
+ const unsigned int noroot = SECBIT_NOROOT | SECBIT_NOROOT_LOCKED;
+ cap_t cap_p;
+
+ if ((cap_get_secbits() & noroot) != noroot)
+ EXPECT_EQ(0, cap_set_secbits(noroot));
+
+ cap_p = cap_get_proc();
+ EXPECT_NE(NULL, cap_p);
+ EXPECT_NE(-1, cap_clear(cap_p));
+
+ /*
+ * Drops everything, especially CAP_SETPCAP, CAP_DAC_OVERRIDE, and
+ * CAP_DAC_READ_SEARCH.
+ */
+ EXPECT_NE(-1, cap_set_proc(cap_p));
+ EXPECT_NE(-1, cap_free(cap_p));
+}
+
+static int test_secbits_set(const unsigned int secbits)
+{
+ int err;
+
+ err = prctl(PR_SET_SECUREBITS, secbits);
+ if (err)
+ return errno;
+ return 0;
+}
+
+FIXTURE(access)
+{
+ int memfd, pipefd;
+ int pipe_fds[2], socket_fds[2];
+};
+
+FIXTURE_VARIANT(access)
+{
+ const bool mount_exec;
+ const bool file_exec;
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(access, mount_exec_file_exec) {
+ /* clang-format on */
+ .mount_exec = true,
+ .file_exec = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(access, mount_exec_file_noexec) {
+ /* clang-format on */
+ .mount_exec = true,
+ .file_exec = false,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(access, mount_noexec_file_exec) {
+ /* clang-format on */
+ .mount_exec = false,
+ .file_exec = true,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(access, mount_noexec_file_noexec) {
+ /* clang-format on */
+ .mount_exec = false,
+ .file_exec = false,
+};
+
+static const char binary_path[] = "./false";
+static const char workdir_path[] = "./test-mount";
+static const char reg_file_path[] = "./test-mount/regular_file";
+static const char dir_path[] = "./test-mount/directory";
+static const char block_dev_path[] = "./test-mount/block_device";
+static const char char_dev_path[] = "./test-mount/character_device";
+static const char fifo_path[] = "./test-mount/fifo";
+
+FIXTURE_SETUP(access)
+{
+ int procfd_path_size;
+ static const char path_template[] = "/proc/self/fd/%d";
+ char procfd_path[sizeof(path_template) + 10];
+
+ /* Makes sure we are not already restricted nor locked. */
+ EXPECT_EQ(0, test_secbits_set(0));
+
+ /*
+ * Cleans previous workspace if any error previously happened (don't
+ * check errors).
+ */
+ umount(workdir_path);
+ rmdir(workdir_path);
+
+ /* Creates a clean mount point. */
+ ASSERT_EQ(0, mkdir(workdir_path, 00700));
+ ASSERT_EQ(0, mount("test", workdir_path, "tmpfs",
+ MS_MGC_VAL | (variant->mount_exec ? 0 : MS_NOEXEC),
+ "mode=0700,size=9m"));
+
+ /* Creates a regular file. */
+ ASSERT_EQ(0, mknod(reg_file_path,
+ S_IFREG | (variant->file_exec ? 0700 : 0600), 0));
+ /* Creates a directory. */
+ ASSERT_EQ(0, mkdir(dir_path, variant->file_exec ? 0700 : 0600));
+ /* Creates a character device: /dev/null. */
+ ASSERT_EQ(0, mknod(char_dev_path, S_IFCHR | 0400, makedev(1, 3)));
+ /* Creates a block device: /dev/loop0 */
+ ASSERT_EQ(0, mknod(block_dev_path, S_IFBLK | 0400, makedev(7, 0)));
+ /* Creates a fifo. */
+ ASSERT_EQ(0, mknod(fifo_path, S_IFIFO | 0600, 0));
+
+ /* Creates a regular file without user mount point. */
+ self->memfd = memfd_create("test-exec-probe", MFD_CLOEXEC);
+ ASSERT_LE(0, self->memfd);
+ /* Sets mode, which must be ignored by the exec check. */
+ ASSERT_EQ(0, fchmod(self->memfd, variant->file_exec ? 0700 : 0600));
+
+ /* Creates a pipefs file descriptor. */
+ ASSERT_EQ(0, pipe(self->pipe_fds));
+ procfd_path_size = snprintf(procfd_path, sizeof(procfd_path),
+ path_template, self->pipe_fds[0]);
+ ASSERT_LT(procfd_path_size, sizeof(procfd_path));
+ self->pipefd = open(procfd_path, O_RDWR | O_CLOEXEC);
+ ASSERT_LE(0, self->pipefd);
+ ASSERT_EQ(0, fchmod(self->pipefd, variant->file_exec ? 0700 : 0600));
+
+ /* Creates a socket file descriptor. */
+ ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, 0,
+ self->socket_fds));
+}
+
+FIXTURE_TEARDOWN_PARENT(access)
+{
+ /* There is no need to unlink the test files. */
+ EXPECT_EQ(0, umount(workdir_path));
+ EXPECT_EQ(0, rmdir(workdir_path));
+}
+
+static void fill_exec_fd(struct __test_metadata *_metadata, const int fd_out)
+{
+ char buf[1024];
+ size_t len;
+ int fd_in;
+
+ fd_in = open(binary_path, O_CLOEXEC | O_RDONLY);
+ ASSERT_LE(0, fd_in);
+ /* Cannot use copy_file_range(2) because of EXDEV. */
+ len = read(fd_in, buf, sizeof(buf));
+ EXPECT_LE(0, len);
+ while (len > 0) {
+ EXPECT_EQ(len, write(fd_out, buf, len))
+ {
+ TH_LOG("Failed to write: %s (%d)", strerror(errno),
+ errno);
+ }
+ len = read(fd_in, buf, sizeof(buf));
+ EXPECT_LE(0, len);
+ }
+ EXPECT_EQ(0, close(fd_in));
+}
+
+static void fill_exec_path(struct __test_metadata *_metadata,
+ const char *const path)
+{
+ int fd_out;
+
+ fd_out = open(path, O_CLOEXEC | O_WRONLY);
+ ASSERT_LE(0, fd_out)
+ {
+ TH_LOG("Failed to open %s: %s", path, strerror(errno));
+ }
+ fill_exec_fd(_metadata, fd_out);
+ EXPECT_EQ(0, close(fd_out));
+}
+
+static void test_exec_fd(struct __test_metadata *_metadata, const int fd,
+ const int err_code)
+{
+ char *const argv[] = { "", NULL };
+ int access_ret, access_errno;
+
+ /*
+ * If we really execute fd, filled with the "false" binary, the current
+ * thread will exits with an error, which will be interpreted by the
+ * test framework as an error. With AT_EXECVE_CHECK, we only check a
+ * potential successful execution.
+ */
+ access_ret = sys_execveat(fd, "", argv, NULL,
+ AT_EMPTY_PATH | AT_EXECVE_CHECK);
+ access_errno = errno;
+ if (err_code) {
+ EXPECT_EQ(-1, access_ret);
+ EXPECT_EQ(err_code, access_errno)
+ {
+ TH_LOG("Wrong error for execveat(2): %s (%d)",
+ strerror(access_errno), errno);
+ }
+ } else {
+ EXPECT_EQ(0, access_ret)
+ {
+ TH_LOG("Access denied: %s", strerror(access_errno));
+ }
+ }
+}
+
+static void test_exec_path(struct __test_metadata *_metadata,
+ const char *const path, const int err_code)
+{
+ int flags = O_CLOEXEC;
+ int fd;
+
+ /* Do not block on pipes. */
+ if (path == fifo_path)
+ flags |= O_NONBLOCK;
+
+ fd = open(path, flags | O_RDONLY);
+ ASSERT_LE(0, fd)
+ {
+ TH_LOG("Failed to open %s: %s", path, strerror(errno));
+ }
+ test_exec_fd(_metadata, fd, err_code);
+ EXPECT_EQ(0, close(fd));
+}
+
+/* Tests that we don't get ENOEXEC. */
+TEST_F(access, regular_file_empty)
+{
+ const int exec = variant->mount_exec && variant->file_exec;
+
+ test_exec_path(_metadata, reg_file_path, exec ? 0 : EACCES);
+
+ drop_privileges(_metadata);
+ test_exec_path(_metadata, reg_file_path, exec ? 0 : EACCES);
+}
+
+TEST_F(access, regular_file_elf)
+{
+ const int exec = variant->mount_exec && variant->file_exec;
+
+ fill_exec_path(_metadata, reg_file_path);
+
+ test_exec_path(_metadata, reg_file_path, exec ? 0 : EACCES);
+
+ drop_privileges(_metadata);
+ test_exec_path(_metadata, reg_file_path, exec ? 0 : EACCES);
+}
+
+/* Tests that we don't get ENOEXEC. */
+TEST_F(access, memfd_empty)
+{
+ const int exec = variant->file_exec;
+
+ test_exec_fd(_metadata, self->memfd, exec ? 0 : EACCES);
+
+ drop_privileges(_metadata);
+ test_exec_fd(_metadata, self->memfd, exec ? 0 : EACCES);
+}
+
+TEST_F(access, memfd_elf)
+{
+ const int exec = variant->file_exec;
+
+ fill_exec_fd(_metadata, self->memfd);
+
+ test_exec_fd(_metadata, self->memfd, exec ? 0 : EACCES);
+
+ drop_privileges(_metadata);
+ test_exec_fd(_metadata, self->memfd, exec ? 0 : EACCES);
+}
+
+TEST_F(access, non_regular_files)
+{
+ test_exec_path(_metadata, dir_path, EACCES);
+ test_exec_path(_metadata, block_dev_path, EACCES);
+ test_exec_path(_metadata, char_dev_path, EACCES);
+ test_exec_path(_metadata, fifo_path, EACCES);
+ test_exec_fd(_metadata, self->socket_fds[0], EACCES);
+ test_exec_fd(_metadata, self->pipefd, EACCES);
+}
+
+/* clang-format off */
+FIXTURE(secbits) {};
+/* clang-format on */
+
+FIXTURE_VARIANT(secbits)
+{
+ const bool is_privileged;
+ const int error;
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(secbits, priv) {
+ /* clang-format on */
+ .is_privileged = true,
+ .error = 0,
+};
+
+/* clang-format off */
+FIXTURE_VARIANT_ADD(secbits, unpriv) {
+ /* clang-format on */
+ .is_privileged = false,
+ .error = EPERM,
+};
+
+FIXTURE_SETUP(secbits)
+{
+ /* Makes sure no exec bits are set. */
+ EXPECT_EQ(0, test_secbits_set(0));
+ EXPECT_EQ(0, prctl(PR_GET_SECUREBITS));
+
+ if (!variant->is_privileged)
+ drop_privileges(_metadata);
+}
+
+FIXTURE_TEARDOWN(secbits)
+{
+}
+
+TEST_F(secbits, legacy)
+{
+ EXPECT_EQ(variant->error, test_secbits_set(0));
+}
+
+#define CHILD(...) \
+ do { \
+ pid_t child = vfork(); \
+ EXPECT_LE(0, child); \
+ if (child == 0) { \
+ __VA_ARGS__; \
+ _exit(0); \
+ } \
+ } while (0)
+
+TEST_F(secbits, exec)
+{
+ unsigned int secbits = prctl(PR_GET_SECUREBITS);
+
+ secbits |= SECBIT_EXEC_RESTRICT_FILE;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+ EXPECT_EQ(secbits, prctl(PR_GET_SECUREBITS));
+ CHILD(EXPECT_EQ(secbits, prctl(PR_GET_SECUREBITS)));
+
+ secbits |= SECBIT_EXEC_DENY_INTERACTIVE;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+ EXPECT_EQ(secbits, prctl(PR_GET_SECUREBITS));
+ CHILD(EXPECT_EQ(secbits, prctl(PR_GET_SECUREBITS)));
+
+ secbits &= ~(SECBIT_EXEC_RESTRICT_FILE | SECBIT_EXEC_DENY_INTERACTIVE);
+ EXPECT_EQ(0, test_secbits_set(secbits));
+ EXPECT_EQ(secbits, prctl(PR_GET_SECUREBITS));
+ CHILD(EXPECT_EQ(secbits, prctl(PR_GET_SECUREBITS)));
+}
+
+TEST_F(secbits, check_locked_set)
+{
+ unsigned int secbits = prctl(PR_GET_SECUREBITS);
+
+ secbits |= SECBIT_EXEC_RESTRICT_FILE;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+ secbits |= SECBIT_EXEC_RESTRICT_FILE_LOCKED;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+
+ /* Checks lock set but unchanged. */
+ EXPECT_EQ(variant->error, test_secbits_set(secbits));
+ CHILD(EXPECT_EQ(variant->error, test_secbits_set(secbits)));
+
+ secbits &= ~SECBIT_EXEC_RESTRICT_FILE;
+ EXPECT_EQ(EPERM, test_secbits_set(0));
+ CHILD(EXPECT_EQ(EPERM, test_secbits_set(0)));
+}
+
+TEST_F(secbits, check_locked_unset)
+{
+ unsigned int secbits = prctl(PR_GET_SECUREBITS);
+
+ secbits |= SECBIT_EXEC_RESTRICT_FILE_LOCKED;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+
+ /* Checks lock unset but unchanged. */
+ EXPECT_EQ(variant->error, test_secbits_set(secbits));
+ CHILD(EXPECT_EQ(variant->error, test_secbits_set(secbits)));
+
+ secbits &= ~SECBIT_EXEC_RESTRICT_FILE;
+ EXPECT_EQ(EPERM, test_secbits_set(0));
+ CHILD(EXPECT_EQ(EPERM, test_secbits_set(0)));
+}
+
+TEST_F(secbits, restrict_locked_set)
+{
+ unsigned int secbits = prctl(PR_GET_SECUREBITS);
+
+ secbits |= SECBIT_EXEC_DENY_INTERACTIVE;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+ secbits |= SECBIT_EXEC_DENY_INTERACTIVE_LOCKED;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+
+ /* Checks lock set but unchanged. */
+ EXPECT_EQ(variant->error, test_secbits_set(secbits));
+ CHILD(EXPECT_EQ(variant->error, test_secbits_set(secbits)));
+
+ secbits &= ~SECBIT_EXEC_DENY_INTERACTIVE;
+ EXPECT_EQ(EPERM, test_secbits_set(0));
+ CHILD(EXPECT_EQ(EPERM, test_secbits_set(0)));
+}
+
+TEST_F(secbits, restrict_locked_unset)
+{
+ unsigned int secbits = prctl(PR_GET_SECUREBITS);
+
+ secbits |= SECBIT_EXEC_DENY_INTERACTIVE_LOCKED;
+ EXPECT_EQ(0, test_secbits_set(secbits));
+
+ /* Checks lock unset but unchanged. */
+ EXPECT_EQ(variant->error, test_secbits_set(secbits));
+ CHILD(EXPECT_EQ(variant->error, test_secbits_set(secbits)));
+
+ secbits &= ~SECBIT_EXEC_DENY_INTERACTIVE;
+ EXPECT_EQ(EPERM, test_secbits_set(0));
+ CHILD(EXPECT_EQ(EPERM, test_secbits_set(0)));
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/exec/config b/tools/testing/selftests/exec/config
new file mode 100644
index 000000000..c30807986
--- /dev/null
+++ b/tools/testing/selftests/exec/config
@@ -0,0 +1,2 @@
+CONFIG_BLK_DEV=y
+CONFIG_BLK_DEV_LOOP=y
diff --git a/tools/testing/selftests/exec/execveat.c b/tools/testing/selftests/exec/execveat.c
new file mode 100644
index 000000000..d37c068ed
--- /dev/null
+++ b/tools/testing/selftests/exec/execveat.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014 Google, Inc.
+ *
+ * Selftests for execveat(2).
+ */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE /* to get O_PATH, AT_EMPTY_PATH */
+#endif
+#include <sys/sendfile.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "kselftest.h"
+
+#define TESTS_EXPECTED 54
+#define TEST_NAME_LEN (PATH_MAX * 4)
+
+#define CHECK_COMM "CHECK_COMM"
+
+static char longpath[2 * PATH_MAX] = "";
+static char *envp[] = { "IN_TEST=yes", NULL, NULL };
+static char *argv[] = { "execveat", "99", NULL };
+
+static int execveat_(int fd, const char *path, char **argv, char **envp,
+ int flags)
+{
+#ifdef __NR_execveat
+ return syscall(__NR_execveat, fd, path, argv, envp, flags);
+#else
+ errno = ENOSYS;
+ return -1;
+#endif
+}
+
+#define check_execveat_fail(fd, path, flags, errno) \
+ _check_execveat_fail(fd, path, flags, errno, #errno)
+static int _check_execveat_fail(int fd, const char *path, int flags,
+ int expected_errno, const char *errno_str)
+{
+ char test_name[TEST_NAME_LEN];
+ int rc;
+
+ errno = 0;
+ snprintf(test_name, sizeof(test_name),
+ "Check failure of execveat(%d, '%s', %d) with %s",
+ fd, path?:"(null)", flags, errno_str);
+ rc = execveat_(fd, path, argv, envp, flags);
+
+ if (rc > 0) {
+ ksft_print_msg("unexpected success from execveat(2)\n");
+ ksft_test_result_fail("%s\n", test_name);
+ return 1;
+ }
+ if (errno != expected_errno) {
+ ksft_print_msg("expected errno %d (%s) not %d (%s)\n",
+ expected_errno, strerror(expected_errno),
+ errno, strerror(errno));
+ ksft_test_result_fail("%s\n", test_name);
+ return 1;
+ }
+ ksft_test_result_pass("%s\n", test_name);
+ return 0;
+}
+
+static int check_execveat_invoked_rc(int fd, const char *path, int flags,
+ int expected_rc, int expected_rc2)
+{
+ char test_name[TEST_NAME_LEN];
+ int status;
+ int rc;
+ pid_t child;
+ int pathlen = path ? strlen(path) : 0;
+
+ if (pathlen > 40)
+ snprintf(test_name, sizeof(test_name),
+ "Check success of execveat(%d, '%.20s...%s', %d)... ",
+ fd, path, (path + pathlen - 20), flags);
+ else
+ snprintf(test_name, sizeof(test_name),
+ "Check success of execveat(%d, '%s', %d)... ",
+ fd, path?:"(null)", flags);
+
+ child = fork();
+ if (child < 0) {
+ ksft_perror("fork() failed");
+ ksft_test_result_fail("%s\n", test_name);
+ return 1;
+ }
+ if (child == 0) {
+ /* Child: do execveat(). */
+ rc = execveat_(fd, path, argv, envp, flags);
+ ksft_print_msg("child execveat() failed, rc=%d errno=%d (%s)\n",
+ rc, errno, strerror(errno));
+ exit(errno);
+ }
+ /* Parent: wait for & check child's exit status. */
+ rc = waitpid(child, &status, 0);
+ if (rc != child) {
+ ksft_print_msg("waitpid(%d,...) returned %d\n", child, rc);
+ ksft_test_result_fail("%s\n", test_name);
+ return 1;
+ }
+ if (!WIFEXITED(status)) {
+ ksft_print_msg("child %d did not exit cleanly, status=%08x\n",
+ child, status);
+ ksft_test_result_fail("%s\n", test_name);
+ return 1;
+ }
+ if ((WEXITSTATUS(status) != expected_rc) &&
+ (WEXITSTATUS(status) != expected_rc2)) {
+ ksft_print_msg("child %d exited with %d neither %d nor %d\n",
+ child, WEXITSTATUS(status), expected_rc,
+ expected_rc2);
+ ksft_test_result_fail("%s\n", test_name);
+ return 1;
+ }
+ ksft_test_result_pass("%s\n", test_name);
+ return 0;
+}
+
+static int check_execveat(int fd, const char *path, int flags)
+{
+ return check_execveat_invoked_rc(fd, path, flags, 99, 99);
+}
+
+static char *concat(const char *left, const char *right)
+{
+ char *result = malloc(strlen(left) + strlen(right) + 1);
+
+ strcpy(result, left);
+ strcat(result, right);
+ return result;
+}
+
+static int open_or_die(const char *filename, int flags)
+{
+ int fd = open(filename, flags);
+
+ if (fd < 0)
+ ksft_exit_fail_msg("Failed to open '%s'; "
+ "check prerequisites are available\n", filename);
+ return fd;
+}
+
+static void exe_cp(const char *src, const char *dest)
+{
+ int in_fd = open_or_die(src, O_RDONLY);
+ int out_fd = open(dest, O_RDWR|O_CREAT|O_TRUNC, 0755);
+ struct stat info;
+
+ fstat(in_fd, &info);
+ sendfile(out_fd, in_fd, NULL, info.st_size);
+ close(in_fd);
+ close(out_fd);
+}
+
+#define XX_DIR_LEN 200
+static int check_execveat_pathmax(int root_dfd, const char *src, int is_script)
+{
+ int fail = 0;
+ int ii, count, len;
+ char longname[XX_DIR_LEN + 1];
+ int fd;
+
+ if (*longpath == '\0') {
+ /* Create a filename close to PATH_MAX in length */
+ char *cwd = getcwd(NULL, 0);
+
+ if (!cwd) {
+ ksft_perror("Failed to getcwd()");
+ return 2;
+ }
+ strcpy(longpath, cwd);
+ strcat(longpath, "/");
+ memset(longname, 'x', XX_DIR_LEN - 1);
+ longname[XX_DIR_LEN - 1] = '/';
+ longname[XX_DIR_LEN] = '\0';
+ count = (PATH_MAX - 3 - strlen(cwd)) / XX_DIR_LEN;
+ for (ii = 0; ii < count; ii++) {
+ strcat(longpath, longname);
+ mkdir(longpath, 0755);
+ }
+ len = (PATH_MAX - 3 - strlen(cwd)) - (count * XX_DIR_LEN);
+ if (len <= 0)
+ len = 1;
+ memset(longname, 'y', len);
+ longname[len] = '\0';
+ strcat(longpath, longname);
+ free(cwd);
+ }
+ exe_cp(src, longpath);
+
+ /*
+ * Execute as a pre-opened file descriptor, which works whether this is
+ * a script or not (because the interpreter sees a filename like
+ * "/dev/fd/20").
+ */
+ fd = open(longpath, O_RDONLY);
+ if (fd > 0) {
+ ksft_print_msg("Invoke copy of '%s' via filename of length %zu:\n",
+ src, strlen(longpath));
+ fail += check_execveat(fd, "", AT_EMPTY_PATH);
+ } else {
+ ksft_print_msg("Failed to open length %zu filename, errno=%d (%s)\n",
+ strlen(longpath), errno, strerror(errno));
+ fail++;
+ }
+
+ /*
+ * Execute as a long pathname relative to "/". If this is a script,
+ * the interpreter will launch but fail to open the script because its
+ * name ("/dev/fd/5/xxx....") is bigger than PATH_MAX.
+ *
+ * The failure code is usually 127 (POSIX: "If a command is not found,
+ * the exit status shall be 127."), but some systems give 126 (POSIX:
+ * "If the command name is found, but it is not an executable utility,
+ * the exit status shall be 126."), so allow either.
+ */
+ if (is_script) {
+ ksft_print_msg("Invoke script via root_dfd and relative filename\n");
+ fail += check_execveat_invoked_rc(root_dfd, longpath + 1, 0,
+ 127, 126);
+ } else {
+ ksft_print_msg("Invoke exec via root_dfd and relative filename\n");
+ fail += check_execveat(root_dfd, longpath + 1, 0);
+ }
+
+ return fail;
+}
+
+static int check_execveat_comm(int fd, char *argv0, char *expected)
+{
+ char buf[128], *old_env, *old_argv0;
+ int ret;
+
+ snprintf(buf, sizeof(buf), CHECK_COMM "=%s", expected);
+
+ old_env = envp[1];
+ envp[1] = buf;
+
+ old_argv0 = argv[0];
+ argv[0] = argv0;
+
+ ksft_print_msg("Check execveat(AT_EMPTY_PATH)'s comm is %s\n",
+ expected);
+ ret = check_execveat_invoked_rc(fd, "", AT_EMPTY_PATH, 0, 0);
+
+ envp[1] = old_env;
+ argv[0] = old_argv0;
+
+ return ret;
+}
+
+static int run_tests(void)
+{
+ int fail = 0;
+ char *fullname = realpath("execveat", NULL);
+ char *fullname_script = realpath("script", NULL);
+ char *fullname_symlink = concat(fullname, ".symlink");
+ int subdir_dfd = open_or_die("subdir", O_DIRECTORY|O_RDONLY);
+ int subdir_dfd_ephemeral = open_or_die("subdir.ephemeral",
+ O_DIRECTORY|O_RDONLY);
+ int dot_dfd = open_or_die(".", O_DIRECTORY|O_RDONLY);
+ int root_dfd = open_or_die("/", O_DIRECTORY|O_RDONLY);
+ int dot_dfd_path = open_or_die(".", O_DIRECTORY|O_RDONLY|O_PATH);
+ int dot_dfd_cloexec = open_or_die(".", O_DIRECTORY|O_RDONLY|O_CLOEXEC);
+ int fd = open_or_die("execveat", O_RDONLY);
+ int fd_path = open_or_die("execveat", O_RDONLY|O_PATH);
+ int fd_symlink = open_or_die("execveat.symlink", O_RDONLY);
+ int fd_denatured = open_or_die("execveat.denatured", O_RDONLY);
+ int fd_denatured_path = open_or_die("execveat.denatured",
+ O_RDONLY|O_PATH);
+ int fd_script = open_or_die("script", O_RDONLY);
+ int fd_ephemeral = open_or_die("execveat.ephemeral", O_RDONLY);
+ int fd_ephemeral_path = open_or_die("execveat.path.ephemeral",
+ O_RDONLY|O_PATH);
+ int fd_script_ephemeral = open_or_die("script.ephemeral", O_RDONLY);
+ int fd_cloexec = open_or_die("execveat", O_RDONLY|O_CLOEXEC);
+ int fd_script_cloexec = open_or_die("script", O_RDONLY|O_CLOEXEC);
+
+ /* Check if we have execveat at all, and bail early if not */
+ errno = 0;
+ execveat_(-1, NULL, NULL, NULL, 0);
+ if (errno == ENOSYS) {
+ ksft_exit_skip(
+ "ENOSYS calling execveat - no kernel support?\n");
+ }
+
+ /* Change file position to confirm it doesn't affect anything */
+ lseek(fd, 10, SEEK_SET);
+
+ /* Normal executable file: */
+ /* dfd + path */
+ fail += check_execveat(subdir_dfd, "../execveat", 0);
+ fail += check_execveat(dot_dfd, "execveat", 0);
+ fail += check_execveat(dot_dfd_path, "execveat", 0);
+ /* absolute path */
+ fail += check_execveat(AT_FDCWD, fullname, 0);
+ /* absolute path with nonsense dfd */
+ fail += check_execveat(99, fullname, 0);
+ /* fd + no path */
+ fail += check_execveat(fd, "", AT_EMPTY_PATH);
+ /* O_CLOEXEC fd + no path */
+ fail += check_execveat(fd_cloexec, "", AT_EMPTY_PATH);
+ /* O_PATH fd */
+ fail += check_execveat(fd_path, "", AT_EMPTY_PATH);
+
+ /* Mess with executable file that's already open: */
+ /* fd + no path to a file that's been renamed */
+ rename("execveat.ephemeral", "execveat.moved");
+ fail += check_execveat(fd_ephemeral, "", AT_EMPTY_PATH);
+ /* fd + no path to a file that's been deleted */
+ unlink("execveat.moved"); /* remove the file now fd open */
+ fail += check_execveat(fd_ephemeral, "", AT_EMPTY_PATH);
+
+ /* Mess with executable file that's already open with O_PATH */
+ /* fd + no path to a file that's been deleted */
+ unlink("execveat.path.ephemeral");
+ fail += check_execveat(fd_ephemeral_path, "", AT_EMPTY_PATH);
+
+ /* Invalid argument failures */
+ fail += check_execveat_fail(fd, "", 0, ENOENT);
+ fail += check_execveat_fail(fd, NULL, AT_EMPTY_PATH, EFAULT);
+
+ /* Symlink to executable file: */
+ /* dfd + path */
+ fail += check_execveat(dot_dfd, "execveat.symlink", 0);
+ fail += check_execveat(dot_dfd_path, "execveat.symlink", 0);
+ /* absolute path */
+ fail += check_execveat(AT_FDCWD, fullname_symlink, 0);
+ /* fd + no path, even with AT_SYMLINK_NOFOLLOW (already followed) */
+ fail += check_execveat(fd_symlink, "", AT_EMPTY_PATH);
+ fail += check_execveat(fd_symlink, "",
+ AT_EMPTY_PATH|AT_SYMLINK_NOFOLLOW);
+
+ /* Symlink fails when AT_SYMLINK_NOFOLLOW set: */
+ /* dfd + path */
+ fail += check_execveat_fail(dot_dfd, "execveat.symlink",
+ AT_SYMLINK_NOFOLLOW, ELOOP);
+ fail += check_execveat_fail(dot_dfd_path, "execveat.symlink",
+ AT_SYMLINK_NOFOLLOW, ELOOP);
+ /* absolute path */
+ fail += check_execveat_fail(AT_FDCWD, fullname_symlink,
+ AT_SYMLINK_NOFOLLOW, ELOOP);
+
+ /* Non-regular file failure */
+ fail += check_execveat_fail(dot_dfd, "pipe", 0, EACCES);
+ unlink("pipe");
+
+ /* Shell script wrapping executable file: */
+ /* dfd + path */
+ fail += check_execveat(subdir_dfd, "../script", 0);
+ fail += check_execveat(dot_dfd, "script", 0);
+ fail += check_execveat(dot_dfd_path, "script", 0);
+ /* absolute path */
+ fail += check_execveat(AT_FDCWD, fullname_script, 0);
+ /* fd + no path */
+ fail += check_execveat(fd_script, "", AT_EMPTY_PATH);
+ fail += check_execveat(fd_script, "",
+ AT_EMPTY_PATH|AT_SYMLINK_NOFOLLOW);
+ /* O_CLOEXEC fd fails for a script (as script file inaccessible) */
+ fail += check_execveat_fail(fd_script_cloexec, "", AT_EMPTY_PATH,
+ ENOENT);
+ fail += check_execveat_fail(dot_dfd_cloexec, "script", 0, ENOENT);
+
+ /* Mess with script file that's already open: */
+ /* fd + no path to a file that's been renamed */
+ rename("script.ephemeral", "script.moved");
+ fail += check_execveat(fd_script_ephemeral, "", AT_EMPTY_PATH);
+ /* fd + no path to a file that's been deleted */
+ unlink("script.moved"); /* remove the file while fd open */
+ fail += check_execveat(fd_script_ephemeral, "", AT_EMPTY_PATH);
+
+ /* Rename a subdirectory in the path: */
+ rename("subdir.ephemeral", "subdir.moved");
+ fail += check_execveat(subdir_dfd_ephemeral, "../script", 0);
+ fail += check_execveat(subdir_dfd_ephemeral, "script", 0);
+ /* Remove the subdir and its contents */
+ unlink("subdir.moved/script");
+ unlink("subdir.moved");
+ /* Shell loads via deleted subdir OK because name starts with .. */
+ fail += check_execveat(subdir_dfd_ephemeral, "../script", 0);
+ fail += check_execveat_fail(subdir_dfd_ephemeral, "script", 0, ENOENT);
+
+ /* Flag values other than AT_SYMLINK_NOFOLLOW => EINVAL */
+ fail += check_execveat_fail(dot_dfd, "execveat", 0xFFFF, EINVAL);
+ /* Invalid path => ENOENT */
+ fail += check_execveat_fail(dot_dfd, "no-such-file", 0, ENOENT);
+ fail += check_execveat_fail(dot_dfd_path, "no-such-file", 0, ENOENT);
+ fail += check_execveat_fail(AT_FDCWD, "no-such-file", 0, ENOENT);
+ /* Attempt to execute directory => EACCES */
+ fail += check_execveat_fail(dot_dfd, "", AT_EMPTY_PATH, EACCES);
+ /* Attempt to execute non-executable => EACCES */
+ fail += check_execveat_fail(dot_dfd, "Makefile", 0, EACCES);
+ fail += check_execveat_fail(fd_denatured, "", AT_EMPTY_PATH, EACCES);
+ fail += check_execveat_fail(fd_denatured_path, "", AT_EMPTY_PATH,
+ EACCES);
+ /* Attempt to execute nonsense FD => EBADF */
+ fail += check_execveat_fail(99, "", AT_EMPTY_PATH, EBADF);
+ fail += check_execveat_fail(99, "execveat", 0, EBADF);
+ /* Attempt to execute relative to non-directory => ENOTDIR */
+ fail += check_execveat_fail(fd, "execveat", 0, ENOTDIR);
+
+ fail += check_execveat_pathmax(root_dfd, "execveat", 0);
+ fail += check_execveat_pathmax(root_dfd, "script", 1);
+
+ /* /proc/pid/comm gives filename by default */
+ fail += check_execveat_comm(fd, "sentinel", "execveat");
+ /* /proc/pid/comm gives argv[0] when invoked via link */
+ fail += check_execveat_comm(fd_symlink, "sentinel", "execveat");
+ /* /proc/pid/comm gives filename if NULL is passed */
+ fail += check_execveat_comm(fd, NULL, "execveat");
+
+ return fail;
+}
+
+static void prerequisites(void)
+{
+ int fd;
+ const char *script = "#!/bin/bash\nexit $*\n";
+
+ /* Create ephemeral copies of files */
+ exe_cp("execveat", "execveat.ephemeral");
+ exe_cp("execveat", "execveat.path.ephemeral");
+ exe_cp("script", "script.ephemeral");
+ mkdir("subdir.ephemeral", 0755);
+
+ fd = open("subdir.ephemeral/script", O_RDWR|O_CREAT|O_TRUNC, 0755);
+ write(fd, script, strlen(script));
+ close(fd);
+
+ mkfifo("pipe", 0755);
+}
+
+int main(int argc, char **argv)
+{
+ int ii;
+ int rc;
+ const char *verbose = getenv("VERBOSE");
+ const char *check_comm = getenv(CHECK_COMM);
+
+ if (argc >= 2 || check_comm) {
+ /*
+ * If we are invoked with an argument, or no arguments but a
+ * command to check, don't run tests.
+ */
+ const char *in_test = getenv("IN_TEST");
+
+ if (verbose) {
+ ksft_print_msg("invoked with:\n");
+ for (ii = 0; ii < argc; ii++)
+ ksft_print_msg("\t[%d]='%s\n'", ii, argv[ii]);
+ }
+
+ /* If the tests wanted us to check the command, do so. */
+ if (check_comm) {
+ /* TASK_COMM_LEN == 16 */
+ char buf[32];
+ int fd, ret;
+
+ fd = open("/proc/self/comm", O_RDONLY);
+ if (fd < 0) {
+ ksft_perror("open() comm failed");
+ exit(1);
+ }
+
+ ret = read(fd, buf, sizeof(buf));
+ if (ret < 0) {
+ ksft_perror("read() comm failed");
+ close(fd);
+ exit(1);
+ }
+ close(fd);
+
+ // trim off the \n
+ buf[ret-1] = 0;
+
+ if (strcmp(buf, check_comm)) {
+ ksft_print_msg("bad comm, got: %s expected: %s\n",
+ buf, check_comm);
+ exit(1);
+ }
+
+ exit(0);
+ }
+
+ /* Check expected environment transferred. */
+ if (!in_test || strcmp(in_test, "yes") != 0) {
+ ksft_print_msg("no IN_TEST=yes in env\n");
+ return 1;
+ }
+
+ /* Use the final argument as an exit code. */
+ rc = atoi(argv[argc - 1]);
+ exit(rc);
+ } else {
+ ksft_print_header();
+ ksft_set_plan(TESTS_EXPECTED);
+ prerequisites();
+ if (verbose)
+ envp[1] = "VERBOSE=1";
+ rc = run_tests();
+ if (rc > 0)
+ printf("%d tests failed\n", rc);
+ ksft_finished();
+ }
+
+ return rc;
+}
diff --git a/tools/testing/selftests/exec/false.c b/tools/testing/selftests/exec/false.c
new file mode 100644
index 000000000..104383ec3
--- /dev/null
+++ b/tools/testing/selftests/exec/false.c
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0
+int main(void)
+{
+ return 1;
+}
diff --git a/tools/testing/selftests/exec/load_address.c b/tools/testing/selftests/exec/load_address.c
new file mode 100644
index 000000000..55fd3732f
--- /dev/null
+++ b/tools/testing/selftests/exec/load_address.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <link.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include "kselftest.h"
+
+struct Statistics {
+ unsigned long long load_address;
+ unsigned long long alignment;
+ bool interp;
+};
+
+int ExtractStatistics(struct dl_phdr_info *info, size_t size, void *data)
+{
+ struct Statistics *stats = (struct Statistics *) data;
+ int i;
+
+ if (info->dlpi_name != NULL && info->dlpi_name[0] != '\0') {
+ // Ignore headers from other than the executable.
+ return 2;
+ }
+
+ stats->load_address = (unsigned long long) info->dlpi_addr;
+ stats->alignment = 0;
+
+ for (i = 0; i < info->dlpi_phnum; i++) {
+ unsigned long long align;
+
+ if (info->dlpi_phdr[i].p_type == PT_INTERP) {
+ stats->interp = true;
+ continue;
+ }
+
+ if (info->dlpi_phdr[i].p_type != PT_LOAD)
+ continue;
+
+ align = info->dlpi_phdr[i].p_align;
+
+ if (align > stats->alignment)
+ stats->alignment = align;
+ }
+
+ return 1; // Terminate dl_iterate_phdr.
+}
+
+int main(int argc, char **argv)
+{
+ struct Statistics extracted = { };
+ unsigned long long misalign, pow2;
+ bool interp_needed;
+ char buf[1024];
+ FILE *maps;
+ int ret;
+
+ ksft_print_header();
+ ksft_set_plan(4);
+
+ /* Dump maps file for debugging reference. */
+ maps = fopen("/proc/self/maps", "r");
+ if (!maps)
+ ksft_exit_fail_msg("FAILED: /proc/self/maps: %s\n", strerror(errno));
+ while (fgets(buf, sizeof(buf), maps)) {
+ ksft_print_msg("%s", buf);
+ }
+ fclose(maps);
+
+ /* Walk the program headers. */
+ ret = dl_iterate_phdr(ExtractStatistics, &extracted);
+ if (ret != 1)
+ ksft_exit_fail_msg("FAILED: dl_iterate_phdr\n");
+
+ /* Report our findings. */
+ ksft_print_msg("load_address=%#llx alignment=%#llx\n",
+ extracted.load_address, extracted.alignment);
+
+ /* If we're named with ".static." we expect no INTERP. */
+ interp_needed = strstr(argv[0], ".static.") == NULL;
+
+ /* Were we built as expected? */
+ ksft_test_result(interp_needed == extracted.interp,
+ "%s INTERP program header %s\n",
+ interp_needed ? "Wanted" : "Unwanted",
+ extracted.interp ? "seen" : "missing");
+
+ /* Did we find an alignment? */
+ ksft_test_result(extracted.alignment != 0,
+ "Alignment%s found\n", extracted.alignment ? "" : " NOT");
+
+ /* Is the alignment sane? */
+ pow2 = extracted.alignment & (extracted.alignment - 1);
+ ksft_test_result(pow2 == 0,
+ "Alignment is%s a power of 2: %#llx\n",
+ pow2 == 0 ? "" : " NOT", extracted.alignment);
+
+ /* Is the load address aligned? */
+ misalign = extracted.load_address & (extracted.alignment - 1);
+ ksft_test_result(misalign == 0, "Load Address is %saligned (%#llx)\n",
+ misalign ? "MIS" : "", misalign);
+
+ ksft_finished();
+}
diff --git a/tools/testing/selftests/exec/non-regular.c b/tools/testing/selftests/exec/non-regular.c
new file mode 100644
index 000000000..14ac36487
--- /dev/null
+++ b/tools/testing/selftests/exec/non-regular.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <sys/types.h>
+
+#include "kselftest_harness.h"
+
+/* Remove a file, ignoring the result if it didn't exist. */
+void rm(struct __test_metadata *_metadata, const char *pathname,
+ int is_dir)
+{
+ int rc;
+
+ if (is_dir)
+ rc = rmdir(pathname);
+ else
+ rc = unlink(pathname);
+
+ if (rc < 0) {
+ ASSERT_EQ(errno, ENOENT) {
+ TH_LOG("Not ENOENT: %s", pathname);
+ }
+ } else {
+ ASSERT_EQ(rc, 0) {
+ TH_LOG("Failed to remove: %s", pathname);
+ }
+ }
+}
+
+FIXTURE(file) {
+ char *pathname;
+ int is_dir;
+};
+
+FIXTURE_VARIANT(file)
+{
+ const char *name;
+ int expected;
+ int is_dir;
+ void (*setup)(struct __test_metadata *_metadata,
+ FIXTURE_DATA(file) *self,
+ const FIXTURE_VARIANT(file) *variant);
+ int major, minor, mode; /* for mknod() */
+};
+
+void setup_link(struct __test_metadata *_metadata,
+ FIXTURE_DATA(file) *self,
+ const FIXTURE_VARIANT(file) *variant)
+{
+ const char * const paths[] = {
+ "/bin/true",
+ "/usr/bin/true",
+ };
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(paths); i++) {
+ if (access(paths[i], X_OK) == 0) {
+ ASSERT_EQ(symlink(paths[i], self->pathname), 0);
+ return;
+ }
+ }
+ ASSERT_EQ(1, 0) {
+ TH_LOG("Could not find viable 'true' binary");
+ }
+}
+
+FIXTURE_VARIANT_ADD(file, S_IFLNK)
+{
+ .name = "S_IFLNK",
+ .expected = ELOOP,
+ .setup = setup_link,
+};
+
+void setup_dir(struct __test_metadata *_metadata,
+ FIXTURE_DATA(file) *self,
+ const FIXTURE_VARIANT(file) *variant)
+{
+ ASSERT_EQ(mkdir(self->pathname, 0755), 0);
+}
+
+FIXTURE_VARIANT_ADD(file, S_IFDIR)
+{
+ .name = "S_IFDIR",
+ .is_dir = 1,
+ .expected = EACCES,
+ .setup = setup_dir,
+};
+
+void setup_node(struct __test_metadata *_metadata,
+ FIXTURE_DATA(file) *self,
+ const FIXTURE_VARIANT(file) *variant)
+{
+ dev_t dev;
+ int rc;
+
+ dev = makedev(variant->major, variant->minor);
+ rc = mknod(self->pathname, 0755 | variant->mode, dev);
+ ASSERT_EQ(rc, 0) {
+ if (errno == EPERM)
+ SKIP(return, "Please run as root; cannot mknod(%s)",
+ variant->name);
+ }
+}
+
+FIXTURE_VARIANT_ADD(file, S_IFBLK)
+{
+ .name = "S_IFBLK",
+ .expected = EACCES,
+ .setup = setup_node,
+ /* /dev/loop0 */
+ .major = 7,
+ .minor = 0,
+ .mode = S_IFBLK,
+};
+
+FIXTURE_VARIANT_ADD(file, S_IFCHR)
+{
+ .name = "S_IFCHR",
+ .expected = EACCES,
+ .setup = setup_node,
+ /* /dev/zero */
+ .major = 1,
+ .minor = 5,
+ .mode = S_IFCHR,
+};
+
+void setup_fifo(struct __test_metadata *_metadata,
+ FIXTURE_DATA(file) *self,
+ const FIXTURE_VARIANT(file) *variant)
+{
+ ASSERT_EQ(mkfifo(self->pathname, 0755), 0);
+}
+
+FIXTURE_VARIANT_ADD(file, S_IFIFO)
+{
+ .name = "S_IFIFO",
+ .expected = EACCES,
+ .setup = setup_fifo,
+};
+
+FIXTURE_SETUP(file)
+{
+ ASSERT_GT(asprintf(&self->pathname, "%s.test", variant->name), 6);
+ self->is_dir = variant->is_dir;
+
+ rm(_metadata, self->pathname, variant->is_dir);
+ variant->setup(_metadata, self, variant);
+}
+
+FIXTURE_TEARDOWN(file)
+{
+ rm(_metadata, self->pathname, self->is_dir);
+}
+
+TEST_F(file, exec_errno)
+{
+ char * const argv[2] = { (char * const)self->pathname, NULL };
+
+ EXPECT_LT(execv(argv[0], argv), 0);
+ EXPECT_EQ(errno, variant->expected);
+}
+
+/* S_IFSOCK */
+FIXTURE(sock)
+{
+ int fd;
+};
+
+FIXTURE_SETUP(sock)
+{
+ self->fd = socket(AF_INET, SOCK_STREAM, 0);
+ ASSERT_GE(self->fd, 0);
+}
+
+FIXTURE_TEARDOWN(sock)
+{
+ if (self->fd >= 0)
+ ASSERT_EQ(close(self->fd), 0);
+}
+
+TEST_F(sock, exec_errno)
+{
+ char * const argv[2] = { " magic socket ", NULL };
+ char * const envp[1] = { NULL };
+
+ EXPECT_LT(fexecve(self->fd, argv, envp), 0);
+ EXPECT_EQ(errno, EACCES);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/exec/null-argv.c b/tools/testing/selftests/exec/null-argv.c
new file mode 100644
index 000000000..4940aee5b
--- /dev/null
+++ b/tools/testing/selftests/exec/null-argv.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Test that empty argvs are swapped out for a single empty string. */
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include "kselftest.h"
+
+#define FORK(exec) \
+do { \
+ pid = fork(); \
+ if (pid == 0) { \
+ /* Child */ \
+ exec; /* Some kind of exec */ \
+ perror("# " #exec); \
+ return 1; \
+ } \
+ check_result(pid, #exec); \
+} while (0)
+
+void check_result(pid_t pid, const char *msg)
+{
+ int wstatus;
+
+ if (pid == (pid_t)-1) {
+ perror("# fork");
+ ksft_test_result_fail("fork failed: %s\n", msg);
+ return;
+ }
+ if (waitpid(pid, &wstatus, 0) < 0) {
+ perror("# waitpid");
+ ksft_test_result_fail("waitpid failed: %s\n", msg);
+ return;
+ }
+ if (!WIFEXITED(wstatus)) {
+ ksft_test_result_fail("child did not exit: %s\n", msg);
+ return;
+ }
+ if (WEXITSTATUS(wstatus) != 0) {
+ ksft_test_result_fail("non-zero exit: %s\n", msg);
+ return;
+ }
+ ksft_test_result_pass("%s\n", msg);
+}
+
+int main(int argc, char *argv[], char *envp[])
+{
+ pid_t pid;
+ static char * const args[] = { NULL };
+ static char * const str[] = { "", NULL };
+
+ /* argc counting checks */
+ if (argc < 1) {
+ fprintf(stderr, "# FAIL: saw argc == 0 (old kernel?)\n");
+ return 1;
+ }
+ if (argc != 1) {
+ fprintf(stderr, "# FAIL: unknown argc (%d)\n", argc);
+ return 1;
+ }
+ if (argv[0][0] == '\0') {
+ /* Good, we found a NULL terminated string at argv[0]! */
+ return 0;
+ }
+
+ /* Test runner. */
+ ksft_print_header();
+ ksft_set_plan(5);
+
+ FORK(execve(argv[0], str, NULL));
+ FORK(execve(argv[0], NULL, NULL));
+ FORK(execve(argv[0], NULL, envp));
+ FORK(execve(argv[0], args, NULL));
+ FORK(execve(argv[0], args, envp));
+
+ ksft_exit(ksft_cnt.ksft_pass == ksft_plan);
+}
diff --git a/tools/testing/selftests/exec/recursion-depth.c b/tools/testing/selftests/exec/recursion-depth.c
new file mode 100644
index 000000000..7b5c4f6d1
--- /dev/null
+++ b/tools/testing/selftests/exec/recursion-depth.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2019 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/* Test that pointing #! script interpreter to self doesn't recurse. */
+#include <errno.h>
+#include <sched.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/mount.h>
+#include <unistd.h>
+#include "kselftest.h"
+
+int main(void)
+{
+ int fd, rv;
+
+ ksft_print_header();
+ ksft_set_plan(1);
+
+ if (unshare(CLONE_NEWNS) == -1) {
+ if (errno == ENOSYS || errno == EPERM) {
+ ksft_test_result_skip("error: unshare, errno %d\n", errno);
+ ksft_finished();
+ }
+ ksft_exit_fail_perror("error: unshare");
+ }
+
+ if (mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL) == -1)
+ ksft_exit_fail_perror("error: mount '/'");
+
+ /* Require "exec" filesystem. */
+ if (mount(NULL, "/tmp", "ramfs", 0, NULL) == -1)
+ ksft_exit_fail_perror("error: mount ramfs");
+
+#define FILENAME "/tmp/1"
+
+ fd = creat(FILENAME, 0700);
+ if (fd == -1)
+ ksft_exit_fail_perror("error: creat");
+
+#define S "#!" FILENAME "\n"
+ if (write(fd, S, strlen(S)) != strlen(S))
+ ksft_exit_fail_perror("error: write");
+
+ close(fd);
+
+ rv = execve(FILENAME, NULL, NULL);
+ ksft_test_result(rv == -1 && errno == ELOOP,
+ "execve failed as expected (ret %d, errno %d)\n", rv, errno);
+ ksft_finished();
+}