kselftest: arm64: fake_sigreturn_misaligned_sp

// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (C) 2019 ARM Limited

 *

 * Place a fake sigframe on the stack at a misaligned SP: on sigreturn

 * Kernel must spot this attempt and the test case is expected to be

 * terminated via SEGV.

 */

#include <signal.h>

#include <ucontext.h>

#include "test_signals_utils.h"

#include "testcases.h"

struct fake_sigframe sf;

static int fake_sigreturn_misaligned_run(struct tdescr *td,

					 siginfo_t *si, ucontext_t *uc)

{

	/* just to fill the ucontext_t with something real */

	if (!get_current_context(td, &sf.uc))

		return 1;

	/* Forcing sigframe on misaligned SP (16 + 3) */

	fake_sigreturn(&sf, sizeof(sf), 3);

	return 1;

}

struct tdescr tde = {

		.name = "FAKE_SIGRETURN_MISALIGNED_SP",

		.descr = "Triggers a sigreturn with a misaligned sigframe",

		.sig_ok = SIGSEGV,

		.timeout = 3,

		.run = fake_sigreturn_misaligned_run,

};