Resguardo inicial

linux-7.2.3/tools/testing/selftests/kexec/.gitignore

@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+test_kexec_jump

linux-7.2.3/tools/testing/selftests/kexec/Makefile

@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# Makefile for kexec tests
+
+ARCH ?= $(shell uname -m 2>/dev/null || echo not)
+ARCH_PROCESSED := $(shell echo $(ARCH) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
+
+ifeq ($(ARCH_PROCESSED),$(filter $(ARCH_PROCESSED),x86 ppc64le))
+TEST_PROGS := test_kexec_load.sh test_kexec_file_load.sh
+TEST_FILES := kexec_common_lib.sh
+
+include ../../../scripts/Makefile.arch
+
+ifeq ($(IS_64_BIT)$(ARCH_PROCESSED),1x86)
+TEST_PROGS += test_kexec_jump.sh
+TEST_GEN_PROGS := test_kexec_jump
+endif
+
+include ../lib.mk
+
+endif

linux-7.2.3/tools/testing/selftests/kexec/config

@@ -0,0 +1,3 @@
+CONFIG_IMA_APPRAISE=y
+CONFIG_IMA_ARCH_POLICY=y
+CONFIG_SECURITYFS=y

linux-7.2.3/tools/testing/selftests/kexec/kexec_common_lib.sh

@@ -0,0 +1,219 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Kselftest framework defines: ksft_pass=0, ksft_fail=1, ksft_skip=4
+
+VERBOSE="${VERBOSE:-1}"
+IKCONFIG="/tmp/config-`uname -r`"
+KERNEL_IMAGE="/boot/vmlinuz-`uname -r`"
+SECURITYFS=$(grep "securityfs" /proc/mounts | awk '{print $2}')
+
+log_info()
+{
+	[ $VERBOSE -ne 0 ] && echo "[INFO] $1"
+}
+
+# The ksefltest framework requirement returns 0 for PASS.
+log_pass()
+{
+	[ $VERBOSE -ne 0 ] && echo "$1 [PASS]"
+	exit 0
+}
+
+# The ksefltest framework requirement returns 1 for FAIL.
+log_fail()
+{
+	[ $VERBOSE -ne 0 ] && echo "$1 [FAIL]"
+	exit 1
+}
+
+# The ksefltest framework requirement returns 4 for SKIP.
+log_skip()
+{
+	[ $VERBOSE -ne 0 ] && echo "$1"
+	exit 4
+}
+
+# Check efivar SecureBoot-$(the UUID) and SetupMode-$(the UUID).
+# (Based on kdump-lib.sh)
+get_efivarfs_secureboot_mode()
+{
+	local efivarfs="/sys/firmware/efi/efivars"
+	local secure_boot_file=""
+	local setup_mode_file=""
+	local secureboot_mode=0
+	local setup_mode=0
+
+	# Make sure that efivar_fs is mounted in the normal location
+	if ! grep -q "^\S\+ $efivarfs efivarfs" /proc/mounts; then
+		log_info "efivars is not mounted on $efivarfs"
+		return 0;
+	fi
+	secure_boot_file=$(find "$efivarfs" -name SecureBoot-* 2>/dev/null)
+	setup_mode_file=$(find "$efivarfs" -name SetupMode-* 2>/dev/null)
+	if [ -f "$secure_boot_file" ] && [ -f "$setup_mode_file" ]; then
+		secureboot_mode=$(hexdump -v -e '/1 "%d\ "' \
+			"$secure_boot_file"|cut -d' ' -f 5)
+		setup_mode=$(hexdump -v -e '/1 "%d\ "' \
+			"$setup_mode_file"|cut -d' ' -f 5)
+
+		if [ $secureboot_mode -eq 1 ] && [ $setup_mode -eq 0 ]; then
+			log_info "secure boot mode enabled (CONFIG_EFIVAR_FS)"
+			return 1;
+		fi
+	fi
+	return 0;
+}
+
+# On powerpc platform, check device-tree property
+# /proc/device-tree/ibm,secureboot/os-secureboot-enforcing
+# to detect secureboot state.
+get_ppc64_secureboot_mode()
+{
+	local secure_boot_file="/proc/device-tree/ibm,secureboot/os-secureboot-enforcing"
+	# Check for secure boot file existence
+	if [ -f $secure_boot_file ]; then
+		log_info "Secureboot is enabled (Device tree)"
+		return 1;
+	fi
+	log_info "Secureboot is not enabled (Device tree)"
+	return 0;
+}
+
+# Return the architecture of the system
+get_arch()
+{
+	echo $(arch)
+}
+
+# Check efivar SecureBoot-$(the UUID) and SetupMode-$(the UUID).
+# The secure boot mode can be accessed as the last integer of
+# "od -An -t u1 /sys/firmware/efi/efivars/SecureBoot-*".  The efi
+# SetupMode can be similarly accessed.
+# Return 1 for SecureBoot mode enabled and SetupMode mode disabled.
+get_secureboot_mode()
+{
+	local secureboot_mode=0
+	local system_arch=$(get_arch)
+
+	if [ "$system_arch" == "ppc64le" ]; then
+		get_ppc64_secureboot_mode
+		secureboot_mode=$?
+	else
+		get_efivarfs_secureboot_mode
+		secureboot_mode=$?
+	fi
+
+	if [ $secureboot_mode -eq 0 ]; then
+		log_info "secure boot mode not enabled"
+	fi
+	return $secureboot_mode;
+}
+
+require_root_privileges()
+{
+	if [ $(id -ru) -ne 0 ]; then
+		log_skip "requires root privileges"
+	fi
+}
+
+# Look for config option in Kconfig file.
+# Return 1 for found and 0 for not found.
+kconfig_enabled()
+{
+	local config="$1"
+	local msg="$2"
+
+	grep -E -q $config $IKCONFIG
+	if [ $? -eq 0 ]; then
+		log_info "$msg"
+		return 1
+	fi
+	return 0
+}
+
+# Attempt to get the kernel config first by checking the modules directory
+# then via proc, and finally by extracting it from the kernel image or the
+# configs.ko using scripts/extract-ikconfig.
+# Return 1 for found.
+get_kconfig()
+{
+	local proc_config="/proc/config.gz"
+	local module_dir="/lib/modules/`uname -r`"
+	local configs_module="$module_dir/kernel/kernel/configs.ko*"
+
+	if [ -f $module_dir/config ]; then
+		IKCONFIG=$module_dir/config
+		return 1
+	fi
+
+	if [ ! -f $proc_config ]; then
+		modprobe configs > /dev/null 2>&1
+	fi
+	if [ -f $proc_config ]; then
+		cat $proc_config | gunzip > $IKCONFIG 2>/dev/null
+		if [ $? -eq 0 ]; then
+			return 1
+		fi
+	fi
+
+	local extract_ikconfig="$module_dir/source/scripts/extract-ikconfig"
+	if [ ! -f $extract_ikconfig ]; then
+		log_skip "extract-ikconfig not found"
+	fi
+
+	$extract_ikconfig $KERNEL_IMAGE > $IKCONFIG 2>/dev/null
+	if [ $? -eq 1 ]; then
+		if [ ! -f $configs_module ]; then
+			log_skip "CONFIG_IKCONFIG not enabled"
+		fi
+		$extract_ikconfig $configs_module > $IKCONFIG
+		if [ $? -eq 1 ]; then
+			log_skip "CONFIG_IKCONFIG not enabled"
+		fi
+	fi
+	return 1
+}
+
+# Make sure that securityfs is mounted
+mount_securityfs()
+{
+	if [ -z $SECURITYFS ]; then
+		SECURITYFS=/sys/kernel/security
+		mount -t securityfs security $SECURITYFS
+	fi
+
+	if [ ! -d "$SECURITYFS" ]; then
+		log_fail "$SECURITYFS :securityfs is not mounted"
+	fi
+}
+
+# The policy rule format is an "action" followed by key-value pairs.  This
+# function supports up to two key-value pairs, in any order.
+# For example: action func=<keyword> [appraise_type=<type>]
+# Return 1 for found and 0 for not found.
+check_ima_policy()
+{
+	local action="$1"
+	local keypair1="$2"
+	local keypair2="$3"
+	local ret=0
+
+	mount_securityfs
+
+	local ima_policy=$SECURITYFS/ima/policy
+	if [ ! -e $ima_policy ]; then
+		log_fail "$ima_policy not found"
+	fi
+
+	if [ -n $keypair2 ]; then
+		grep -e "^$action.*$keypair1" "$ima_policy" | \
+			grep -q -e "$keypair2"
+	else
+		grep -q -e "^$action.*$keypair1" "$ima_policy"
+	fi
+
+	# invert "grep -q" result, returning 1 for found.
+	[ $? -eq 0 ] && ret=1
+	return $ret
+}

linux-7.2.3/tools/testing/selftests/kexec/test_kexec_file_load.sh

@@ -0,0 +1,243 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Loading a kernel image via the kexec_file_load syscall can verify either
+# the IMA signature stored in the security.ima xattr or the PE signature,
+# both signatures depending on the IMA policy, or none.
+#
+# To determine whether the kernel image is signed, this test depends
+# on pesign and getfattr.  This test also requires the kernel to be
+# built with CONFIG_IKCONFIG enabled and either CONFIG_IKCONFIG_PROC
+# enabled or access to the extract-ikconfig script.
+
+TEST="KEXEC_FILE_LOAD"
+. ./kexec_common_lib.sh
+
+trap "{ rm -f $IKCONFIG ; }" EXIT
+
+# Some of the IMA builtin policies may require the kexec kernel image to
+# be signed, but these policy rules may be replaced with a custom
+# policy.  Only CONFIG_IMA_APPRAISE_REQUIRE_KEXEC_SIGS persists after
+# loading a custom policy.  Check if it is enabled, before reading the
+# IMA runtime sysfs policy file.
+# Return 1 for IMA signature required and 0 for not required.
+is_ima_sig_required()
+{
+	local ret=0
+
+	kconfig_enabled "CONFIG_IMA_APPRAISE_REQUIRE_KEXEC_SIGS=y" \
+		"IMA kernel image signature required"
+	if [ $? -eq 1 ]; then
+		log_info "IMA signature required"
+		return 1
+	fi
+
+	# The architecture specific or a custom policy may require the
+	# kexec kernel image be signed.  Policy rules are walked
+	# sequentially.  As a result, a policy rule may be defined, but
+	# might not necessarily be used.  This test assumes if a policy
+	# rule is specified, that is the intent.
+
+	# First check for appended signature (modsig), then xattr
+	if [ $ima_read_policy -eq 1 ]; then
+		check_ima_policy "appraise" "func=KEXEC_KERNEL_CHECK" \
+			"appraise_type=imasig|modsig"
+		ret=$?
+		if [ $ret -eq 1 ]; then
+			log_info "IMA or appended(modsig) signature required"
+		else
+			check_ima_policy "appraise" "func=KEXEC_KERNEL_CHECK" \
+				"appraise_type=imasig"
+			ret=$?
+			[ $ret -eq 1 ] && log_info "IMA signature required";
+		fi
+	fi
+	return $ret
+}
+
+# The kexec_file_load_test() is complicated enough, require pesign.
+# Return 1 for PE signature found and 0 for not found.
+check_for_pesig()
+{
+	which pesign > /dev/null 2>&1 || log_skip "pesign not found"
+
+	pesign -i $KERNEL_IMAGE --show-signature | grep -q "No signatures"
+	local ret=$?
+	if [ $ret -eq 1 ]; then
+		log_info "kexec kernel image PE signed"
+	else
+		log_info "kexec kernel image not PE signed"
+	fi
+	return $ret
+}
+
+# The kexec_file_load_test() is complicated enough, require getfattr.
+# Return 1 for IMA signature found and 0 for not found.
+check_for_imasig()
+{
+	local ret=0
+
+	which getfattr > /dev/null 2>&1
+	if [ $?	-eq 1 ]; then
+		log_skip "getfattr not found"
+	fi
+
+	line=$(getfattr -n security.ima -e hex --absolute-names $KERNEL_IMAGE 2>&1)
+	echo $line | grep -q "security.ima=0x03"
+	if [ $? -eq 0 ]; then
+		ret=1
+		log_info "kexec kernel image IMA signed"
+	else
+		log_info "kexec kernel image not IMA signed"
+	fi
+	return $ret
+}
+
+# Return 1 for appended signature (modsig) found and 0 for not found.
+check_for_modsig()
+{
+	local module_sig_string="~Module signature appended~"
+	local ret=0
+
+	tail --bytes $((${#module_sig_string} + 1)) $KERNEL_IMAGE | \
+		grep -q "$module_sig_string"
+	if [ $? -eq 0 ]; then
+		ret=1
+		log_info "kexec kernel image modsig signed"
+	else
+		log_info "kexec kernel image not modsig signed"
+	fi
+	return $ret
+}
+
+kexec_file_load_test()
+{
+	local succeed_msg="kexec_file_load succeeded"
+	local failed_msg="kexec_file_load failed"
+	local key_msg="try enabling the CONFIG_INTEGRITY_PLATFORM_KEYRING"
+
+	line=$(kexec --load --kexec-file-syscall $KERNEL_IMAGE 2>&1)
+
+	if [ $? -eq 0 ]; then
+		kexec --unload --kexec-file-syscall
+
+		# In secureboot mode with an architecture  specific
+		# policy, make sure either an IMA or PE signature exists.
+		if [ $secureboot -eq 1 ] && [ $arch_policy -eq 1 ] && \
+			[ $ima_signed -eq 0 ] && [ $pe_signed -eq 0 ] \
+			  && [ $ima_modsig -eq 0 ]; then
+			log_fail "$succeed_msg (missing sig)"
+		fi
+
+		if [ $kexec_sig_required -eq 1 -o $pe_sig_required -eq 1 ] \
+		     && [ $pe_signed -eq 0 ]; then
+			log_fail "$succeed_msg (missing PE sig)"
+		fi
+
+		if [ $ima_sig_required -eq 1 ] && [ $ima_signed -eq 0 ] \
+		     && [ $ima_modsig -eq 0 ]; then
+			log_fail "$succeed_msg (missing IMA sig)"
+		fi
+
+		if [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 1 ] \
+		    && [ $ima_sig_required -eq 0 ] && [ $ima_signed -eq 0 ] \
+	            && [ $ima_read_policy -eq 0 ]; then
+			log_fail "$succeed_msg (possibly missing IMA sig)"
+		fi
+
+		if [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 0 ]; then
+			log_info "No signature verification required"
+		elif [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 1 ] \
+		    && [ $ima_sig_required -eq 0 ] && [ $ima_signed -eq 0 ] \
+	            && [ $ima_read_policy -eq 1 ]; then
+			log_info "No signature verification required"
+		fi
+
+		log_pass "$succeed_msg"
+	fi
+
+	# Check the reason for the kexec_file_load failure
+	echo $line | grep -q "Required key not available"
+	if [ $? -eq 0 ]; then
+		if [ $platform_keyring -eq 0 ]; then
+			log_pass "$failed_msg (-ENOKEY), $key_msg"
+		else
+			log_pass "$failed_msg (-ENOKEY)"
+		fi
+	fi
+
+	if [ $kexec_sig_required -eq 1 -o $pe_sig_required -eq 1 ] \
+	     && [ $pe_signed -eq 0 ]; then
+		log_pass "$failed_msg (missing PE sig)"
+	fi
+
+	if [ $ima_sig_required -eq 1 ] && [ $ima_signed -eq 0 ]; then
+		log_pass "$failed_msg (missing IMA sig)"
+	fi
+
+	if [ $pe_sig_required -eq 0 ] && [ $ima_appraise -eq 1 ] \
+	    && [ $ima_sig_required -eq 0 ] && [ $ima_read_policy -eq 0 ] \
+	    && [ $ima_signed -eq 0 ]; then
+		log_pass "$failed_msg (possibly missing IMA sig)"
+	fi
+
+	log_pass "$failed_msg"
+	return 0
+}
+
+# kexec requires root privileges
+require_root_privileges
+
+# get the kernel config
+get_kconfig
+
+kconfig_enabled "CONFIG_KEXEC_FILE=y" "kexec_file_load is enabled"
+if [ $? -eq 0 ]; then
+	log_skip "kexec_file_load is not enabled"
+fi
+
+# Determine which kernel config options are enabled
+kconfig_enabled "CONFIG_IMA_APPRAISE=y" "IMA enabled"
+ima_appraise=$?
+
+kconfig_enabled "CONFIG_IMA_ARCH_POLICY=y" \
+	"architecture specific policy enabled"
+arch_policy=$?
+
+kconfig_enabled "CONFIG_INTEGRITY_PLATFORM_KEYRING=y" \
+	"platform keyring enabled"
+platform_keyring=$?
+
+kconfig_enabled "CONFIG_IMA_READ_POLICY=y" "reading IMA policy permitted"
+ima_read_policy=$?
+
+kconfig_enabled "CONFIG_KEXEC_SIG_FORCE=y" \
+	"kexec signed kernel image required"
+kexec_sig_required=$?
+
+kconfig_enabled "CONFIG_KEXEC_BZIMAGE_VERIFY_SIG=y" \
+	"PE signed kernel image required"
+pe_sig_required=$?
+
+is_ima_sig_required
+ima_sig_required=$?
+
+get_secureboot_mode
+secureboot=$?
+
+# Are there pe and ima signatures
+if [ "$(get_arch)" == 'ppc64le' ]; then
+	pe_signed=0
+else
+	check_for_pesig
+	pe_signed=$?
+fi
+
+check_for_imasig
+ima_signed=$?
+
+check_for_modsig
+ima_modsig=$?
+
+# Test loading the kernel image via kexec_file_load syscall
+kexec_file_load_test

linux-7.2.3/tools/testing/selftests/kexec/test_kexec_jump.c

@@ -0,0 +1,72 @@
+#include <unistd.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <linux/kexec.h>
+#include <linux/reboot.h>
+#include <sys/reboot.h>
+#include <sys/syscall.h>
+
+asm(
+    "  .code64\n"
+    "  .data\n"
+    "purgatory_start:\n"
+
+    // Trigger kexec debug exception handling
+    "  int3\n"
+
+    // Set load address for next time
+    "  leaq purgatory_start_b(%rip), %r11\n"
+    "  movq %r11, 8(%rsp)\n"
+
+    // Back to Linux
+    "  ret\n"
+
+    // Same again
+    "purgatory_start_b:\n"
+
+    // Trigger kexec debug exception handling
+    "  int3\n"
+
+    // Set load address for next time
+    "  leaq purgatory_start(%rip), %r11\n"
+    "  movq %r11, 8(%rsp)\n"
+
+    // Back to Linux
+    "  ret\n"
+
+    "purgatory_end:\n"
+    ".previous"
+);
+extern char purgatory_start[], purgatory_end[];
+
+int main (void)
+{
+        struct kexec_segment segment = {};
+	int ret;
+
+	segment.buf = purgatory_start;
+	segment.bufsz = purgatory_end - purgatory_start;
+	segment.mem = (void *)0x400000;
+	segment.memsz = 0x1000;
+	ret = syscall(__NR_kexec_load, 0x400000, 1, &segment, KEXEC_PRESERVE_CONTEXT);
+	if (ret) {
+		perror("kexec_load");
+		exit(1);
+	}
+
+	ret = syscall(__NR_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_KEXEC);
+	if (ret) {
+		perror("kexec reboot");
+		exit(1);
+	}
+
+	ret = syscall(__NR_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_KEXEC);
+	if (ret) {
+		perror("kexec reboot");
+		exit(1);
+	}
+	printf("Success\n");
+	return 0;
+}
+

linux-7.2.3/tools/testing/selftests/kexec/test_kexec_jump.sh

@@ -0,0 +1,42 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Prevent loading a kernel image via the kexec_load syscall when
+# signatures are required.  (Dependent on CONFIG_IMA_ARCH_POLICY.)
+
+TEST="$0"
+. ./kexec_common_lib.sh
+
+# kexec requires root privileges
+require_root_privileges
+
+# get the kernel config
+get_kconfig
+
+kconfig_enabled "CONFIG_KEXEC_JUMP=y" "kexec_jump is enabled"
+if [ $? -eq 0 ]; then
+	log_skip "kexec_jump is not enabled"
+fi
+
+kconfig_enabled "CONFIG_IMA_APPRAISE=y" "IMA enabled"
+ima_appraise=$?
+
+kconfig_enabled "CONFIG_IMA_ARCH_POLICY=y" \
+	"IMA architecture specific policy enabled"
+arch_policy=$?
+
+get_secureboot_mode
+secureboot=$?
+
+if [ $secureboot -eq 1 ] && [ $arch_policy -eq 1 ]; then
+    log_skip "Secure boot and CONFIG_IMA_ARCH_POLICY are enabled"
+fi
+
+./test_kexec_jump
+if [ $? -eq 0 ]; then
+    log_pass "kexec_jump succeeded"
+else
+    # The more likely failure mode if anything went wrong is that the
+    # kernel just crashes. But if we get back here, sure, whine anyway.
+    log_fail "kexec_jump failed"
+fi

linux-7.2.3/tools/testing/selftests/kexec/test_kexec_load.sh

@@ -0,0 +1,47 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Prevent loading a kernel image via the kexec_load syscall when
+# signatures are required.  (Dependent on CONFIG_IMA_ARCH_POLICY.)
+
+TEST="$0"
+. ./kexec_common_lib.sh
+
+# kexec requires root privileges
+require_root_privileges
+
+# get the kernel config
+get_kconfig
+
+kconfig_enabled "CONFIG_KEXEC=y" "kexec_load is enabled"
+if [ $? -eq 0 ]; then
+	log_skip "kexec_load is not enabled"
+fi
+
+kconfig_enabled "CONFIG_IMA_APPRAISE=y" "IMA enabled"
+ima_appraise=$?
+
+kconfig_enabled "CONFIG_IMA_ARCH_POLICY=y" \
+	"IMA architecture specific policy enabled"
+arch_policy=$?
+
+get_secureboot_mode
+secureboot=$?
+
+# kexec_load should fail in secure boot mode and CONFIG_IMA_ARCH_POLICY enabled
+kexec --load $KERNEL_IMAGE > /dev/null 2>&1
+if [ $? -eq 0 ]; then
+	kexec --unload
+	if [ $secureboot -eq 1 ] && [ $arch_policy -eq 1 ]; then
+		log_fail "kexec_load succeeded"
+	elif [ $ima_appraise -eq 0 -o $arch_policy -eq 0 ]; then
+		log_info "Either IMA or the IMA arch policy is not enabled"
+	fi
+	log_pass "kexec_load succeeded"
+else
+	if [ $secureboot -eq 1 ] && [ $arch_policy -eq 1 ] ; then
+		log_pass "kexec_load failed"
+	else
+		log_fail "kexec_load failed"
+	fi
+fi