diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/exec/.gitignore | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/exec/Makefile | 14 | ||||
| -rwxr-xr-x | tools/testing/selftests/exec/check-exec-tests.sh | 205 |
3 files changed, 219 insertions, 2 deletions
diff --git a/tools/testing/selftests/exec/.gitignore b/tools/testing/selftests/exec/.gitignore index a32c63bb4df1..7f3d1ae762ec 100644 --- a/tools/testing/selftests/exec/.gitignore +++ b/tools/testing/selftests/exec/.gitignore @@ -11,9 +11,11 @@ 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 index 8713d1c862ae..45a3cfc435cf 100644 --- a/tools/testing/selftests/exec/Makefile +++ b/tools/testing/selftests/exec/Makefile @@ -10,9 +10,9 @@ 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 +TEST_PROGS := binfmt_script.py check-exec-tests.sh TEST_GEN_PROGS := execveat non-regular $(ALIGNMENT_TESTS) -TEST_GEN_PROGS_EXTENDED := false +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 @@ -26,6 +26,8 @@ EXTRA_CLEAN := $(OUTPUT)/subdir.moved $(OUTPUT)/execveat.moved $(OUTPUT)/xxxxx* include ../lib.mk +CHECK_EXEC_SAMPLES := $(top_srcdir)/samples/check-exec + $(OUTPUT)/subdir: mkdir -p $@ $(OUTPUT)/script: Makefile @@ -45,3 +47,11 @@ $(OUTPUT)/load_address.static.0x%: load_address.c -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 $< $@ diff --git a/tools/testing/selftests/exec/check-exec-tests.sh b/tools/testing/selftests/exec/check-exec-tests.sh new file mode 100755 index 000000000000..87102906ae3c --- /dev/null +++ b/tools/testing/selftests/exec/check-exec-tests.sh @@ -0,0 +1,205 @@ +#!/usr/bin/env bash +# SPDX-License-Identifier: GPL-2.0 +# +# Test the "inc" interpreter. +# +# See include/uapi/linux/securebits.h, include/uapi/linux/fcntl.h and +# samples/check-exec/inc.c +# +# Copyright © 2024 Microsoft Corporation + +set -u -e -o pipefail + +EXPECTED_OUTPUT="1" +exec 2>/dev/null + +DIR="$(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 |