Commit 5bfa66bf authored by Benjamin Gray's avatar Benjamin Gray Committed by Michael Ellerman
Browse files

selftests/powerpc/dexcr: Add DEXCR prctl interface test 



Some basic tests of the prctl interface of the DEXCR.

Signed-off-by: default avatarBenjamin Gray <bgray@linux.ibm.com>
[mpe: Add missing SPDX tag]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240417112325.728010-6-bgray@linux.ibm.com
parent 628d701f

tools/testing/selftests/powerpc/dexcr/.gitignore

+1 −0
Original line number Diff line number Diff line 
dexcr_test

hashchk_test

lsdexcr

tools/testing/selftests/powerpc/dexcr/Makefile

+3 −1
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TEST_GEN_PROGS := hashchk_test

TEST_GEN_PROGS := dexcr_test hashchk_test

TEST_GEN_FILES := lsdexcr



include ../../lib.mk

include ../flags.mk



CFLAGS += $(KHDR_INCLUDES)



$(OUTPUT)/hashchk_test: CFLAGS += -fno-pie -no-pie $(call cc-option,-mno-rop-protect)



$(TEST_GEN_PROGS): ../harness.c ../utils.c ./dexcr.c

tools/testing/selftests/powerpc/dexcr/dexcr.c

+40 −0
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@@ -3,6 +3,7 @@ 
#include <errno.h>

#include <setjmp.h>

#include <signal.h>

#include <sys/prctl.h>

#include <sys/types.h>

#include <sys/wait.h>
@@ -43,6 +44,45 @@ bool dexcr_exists(void) 
	return exists;

}



unsigned int pr_which_to_aspect(unsigned long which)

{

	switch (which) {

	case PR_PPC_DEXCR_SBHE:

		return DEXCR_PR_SBHE;

	case PR_PPC_DEXCR_IBRTPD:

		return DEXCR_PR_IBRTPD;

	case PR_PPC_DEXCR_SRAPD:

		return DEXCR_PR_SRAPD;

	case PR_PPC_DEXCR_NPHIE:

		return DEXCR_PR_NPHIE;

	default:

		FAIL_IF_EXIT_MSG(true, "unknown PR aspect");

	}

}



int pr_get_dexcr(unsigned long which)

{

	return prctl(PR_PPC_GET_DEXCR, which, 0UL, 0UL, 0UL);

}



int pr_set_dexcr(unsigned long which, unsigned long ctrl)

{

	return prctl(PR_PPC_SET_DEXCR, which, ctrl, 0UL, 0UL);

}



bool pr_dexcr_aspect_supported(unsigned long which)

{

	if (pr_get_dexcr(which) == -1)

		return errno == ENODEV;



	return true;

}



bool pr_dexcr_aspect_editable(unsigned long which)

{

	return pr_get_dexcr(which) & PR_PPC_DEXCR_CTRL_EDITABLE;

}



/*

 * Just test if a bad hashchk triggers a signal, without checking

 * for support or if the NPHIE aspect is enabled.

tools/testing/selftests/powerpc/dexcr/dexcr.h

+10 −0
Original line number Diff line number Diff line
@@ -28,6 +28,16 @@ 


bool dexcr_exists(void);



bool pr_dexcr_aspect_supported(unsigned long which);



bool pr_dexcr_aspect_editable(unsigned long which);



int pr_get_dexcr(unsigned long pr_aspect);



int pr_set_dexcr(unsigned long pr_aspect, unsigned long ctrl);



unsigned int pr_which_to_aspect(unsigned long which);



bool hashchk_triggers(void);



enum dexcr_source {

tools/testing/selftests/powerpc/dexcr/dexcr_test.c

0 → 100644
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// SPDX-License-Identifier: GPL-2.0-or-later



#include <errno.h>

#include <fcntl.h>

#include <stdlib.h>

#include <string.h>

#include <sys/prctl.h>

#include <unistd.h>



#include "dexcr.h"

#include "utils.h"



/*

 * Helper function for testing the behaviour of a newly exec-ed process

 */

static int dexcr_prctl_onexec_test_child(unsigned long which, const char *status)

{

	unsigned long dexcr = mfspr(SPRN_DEXCR_RO);

	unsigned long aspect = pr_which_to_aspect(which);

	int ctrl = pr_get_dexcr(which);



	if (!strcmp(status, "set")) {

		FAIL_IF_EXIT_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET),

				 "setting aspect across exec not applied");



		FAIL_IF_EXIT_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET_ONEXEC),

				 "setting aspect across exec not inherited");



		FAIL_IF_EXIT_MSG(!(aspect & dexcr), "setting aspect across exec did not take effect");

	} else if (!strcmp(status, "clear")) {

		FAIL_IF_EXIT_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR),

				 "clearing aspect across exec not applied");



		FAIL_IF_EXIT_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC),

				 "clearing aspect across exec not inherited");



		FAIL_IF_EXIT_MSG(aspect & dexcr, "clearing aspect across exec did not take effect");

	} else {

		FAIL_IF_EXIT_MSG(true, "unknown expected status");

	}



	return 0;

}



/*

 * Test that the given prctl value can be manipulated freely

 */

static int dexcr_prctl_aspect_test(unsigned long which)

{

	unsigned long aspect = pr_which_to_aspect(which);

	pid_t pid;

	int ctrl;

	int err;

	int errno_save;



	SKIP_IF_MSG(!dexcr_exists(), "DEXCR not supported");

	SKIP_IF_MSG(!pr_dexcr_aspect_supported(which), "DEXCR aspect not supported");

	SKIP_IF_MSG(!pr_dexcr_aspect_editable(which), "DEXCR aspect not editable with prctl");



	/* We reject invalid combinations of arguments */

	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR);

	errno_save = errno;

	FAIL_IF_MSG(err != -1, "simultaneous set and clear should be rejected");

	FAIL_IF_MSG(errno_save != EINVAL, "simultaneous set and clear should be rejected with EINVAL");



	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_SET_ONEXEC | PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC);

	errno_save = errno;

	FAIL_IF_MSG(err != -1, "simultaneous set and clear on exec should be rejected");

	FAIL_IF_MSG(errno_save != EINVAL, "simultaneous set and clear on exec should be rejected with EINVAL");



	/* We set the aspect */

	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_SET);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_SET failed");



	ctrl = pr_get_dexcr(which);

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET), "config value not PR_PPC_DEXCR_CTRL_SET");

	FAIL_IF_MSG(ctrl & PR_PPC_DEXCR_CTRL_CLEAR, "config value unexpected clear flag");

	FAIL_IF_MSG(!(aspect & mfspr(SPRN_DEXCR_RO)), "setting aspect did not take effect");



	/* We clear the aspect */

	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_CLEAR);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_CLEAR failed");



	ctrl = pr_get_dexcr(which);

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR), "config value not PR_PPC_DEXCR_CTRL_CLEAR");

	FAIL_IF_MSG(ctrl & PR_PPC_DEXCR_CTRL_SET, "config value unexpected set flag");

	FAIL_IF_MSG(aspect & mfspr(SPRN_DEXCR_RO), "clearing aspect did not take effect");



	/* We make it set on exec (doesn't change our current value) */

	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_SET_ONEXEC);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_SET_ONEXEC failed");



	ctrl = pr_get_dexcr(which);

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR), "process aspect should still be cleared");

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET_ONEXEC), "config value not PR_PPC_DEXCR_CTRL_SET_ONEXEC");

	FAIL_IF_MSG(ctrl & PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC, "config value unexpected clear on exec flag");

	FAIL_IF_MSG(aspect & mfspr(SPRN_DEXCR_RO), "scheduling aspect to set on exec should not change it now");



	/* We make it clear on exec (doesn't change our current value) */

	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC failed");



	ctrl = pr_get_dexcr(which);

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR), "process aspect config should still be cleared");

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC), "config value not PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC");

	FAIL_IF_MSG(ctrl & PR_PPC_DEXCR_CTRL_SET_ONEXEC, "config value unexpected set on exec flag");

	FAIL_IF_MSG(aspect & mfspr(SPRN_DEXCR_RO), "process aspect should still be cleared");



	/* We allow setting the current and on-exec value in a single call */

	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC failed");



	ctrl = pr_get_dexcr(which);

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET), "config value not PR_PPC_DEXCR_CTRL_SET");

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC), "config value not PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC");

	FAIL_IF_MSG(!(aspect & mfspr(SPRN_DEXCR_RO)), "process aspect should be set");



	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_CLEAR | PR_PPC_DEXCR_CTRL_SET_ONEXEC);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_CLEAR | PR_PPC_DEXCR_CTRL_SET_ONEXEC failed");



	ctrl = pr_get_dexcr(which);

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR), "config value not PR_PPC_DEXCR_CTRL_CLEAR");

	FAIL_IF_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET_ONEXEC), "config value not PR_PPC_DEXCR_CTRL_SET_ONEXEC");

	FAIL_IF_MSG(aspect & mfspr(SPRN_DEXCR_RO), "process aspect should be clear");



	/* Verify the onexec value is applied across exec */

	pid = fork();

	if (!pid) {

		char which_str[32] = {};

		char *args[] = { "dexcr_prctl_onexec_test_child", which_str, "set", NULL };

		unsigned int ctrl = pr_get_dexcr(which);



		sprintf(which_str, "%lu", which);



		FAIL_IF_EXIT_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_SET_ONEXEC),

				 "setting aspect on exec not copied across fork");



		FAIL_IF_EXIT_MSG(mfspr(SPRN_DEXCR_RO) & aspect,

				 "setting aspect on exec wrongly applied to fork");



		execve("/proc/self/exe", args, NULL);

		_exit(errno);

	}

	await_child_success(pid);



	err = pr_set_dexcr(which, PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC);

	FAIL_IF_MSG(err, "PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC failed");



	pid = fork();

	if (!pid) {

		char which_str[32] = {};

		char *args[] = { "dexcr_prctl_onexec_test_child", which_str, "clear", NULL };

		unsigned int ctrl = pr_get_dexcr(which);



		sprintf(which_str, "%lu", which);



		FAIL_IF_EXIT_MSG(!(ctrl & PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC),

				 "clearing aspect on exec not copied across fork");



		FAIL_IF_EXIT_MSG(!(mfspr(SPRN_DEXCR_RO) & aspect),

				 "clearing aspect on exec wrongly applied to fork");



		execve("/proc/self/exe", args, NULL);

		_exit(errno);

	}

	await_child_success(pid);



	return 0;

}



static int dexcr_prctl_ibrtpd_test(void)

{

	return dexcr_prctl_aspect_test(PR_PPC_DEXCR_IBRTPD);

}



static int dexcr_prctl_srapd_test(void)

{

	return dexcr_prctl_aspect_test(PR_PPC_DEXCR_SRAPD);

}



static int dexcr_prctl_nphie_test(void)

{

	return dexcr_prctl_aspect_test(PR_PPC_DEXCR_NPHIE);

}



int main(int argc, char *argv[])

{

	int err = 0;



	/*

	 * Some tests require checking what happens across exec, so we may be

	 * invoked as the child of a particular test

	 */

	if (argc > 1) {

		if (argc == 3 && !strcmp(argv[0], "dexcr_prctl_onexec_test_child")) {

			unsigned long which;



			err = parse_ulong(argv[1], strlen(argv[1]), &which, 10);

			FAIL_IF_MSG(err, "failed to parse which value for child");



			return dexcr_prctl_onexec_test_child(which, argv[2]);

		}



		FAIL_IF_MSG(true, "unknown test case");

	}



	/*

	 * Otherwise we are the main test invocation and run the full suite

	 */

	err |= test_harness(dexcr_prctl_ibrtpd_test, "dexcr_prctl_ibrtpd");

	err |= test_harness(dexcr_prctl_srapd_test, "dexcr_prctl_srapd");

	err |= test_harness(dexcr_prctl_nphie_test, "dexcr_prctl_nphie");



	return err;

}