gcs_exception_fault.c

 1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Copyright (C) 2023 ARM Limited
 4 */
 5
 6#include <errno.h>
 7#include <signal.h>
 8#include <unistd.h>
 9
10#include <sys/mman.h>
11#include <sys/prctl.h>
12
13#include "test_signals_utils.h"
14#include "testcases.h"
15
16/*
17 * We should get this from asm/siginfo.h but the testsuite is being
18 * clever with redefining siginfo_t.
19 */
20#ifndef SEGV_CPERR
21#define SEGV_CPERR 10
22#endif
23
24static inline void gcsss1(uint64_t Xt)
25{
26	asm volatile (
27		"sys #3, C7, C7, #2, %0\n"
28		:
29		: "rZ" (Xt)
30		: "memory");
31}
32
33static int gcs_op_fault_trigger(struct tdescr *td)
34{
35	/*
36	 * The slot below our current GCS should be in a valid GCS but
37	 * must not have a valid cap in it.
38	 */
39	gcsss1(get_gcspr_el0() - 8);
40
41	return 0;
42}
43
44static int gcs_op_fault_signal(struct tdescr *td, siginfo_t *si,
45				  ucontext_t *uc)
46{
47	ASSERT_GOOD_CONTEXT(uc);
48
49	return 1;
50}
51
52struct tdescr tde = {
53	.name = "Invalid GCS operation",
54	.descr = "An invalid GCS operation generates the expected signal",
55	.feats_required = FEAT_GCS,
56	.timeout = 3,
57	.sig_ok = SIGSEGV,
58	.sig_ok_code = SEGV_CPERR,
59	.sanity_disabled = true,
60	.trigger = gcs_op_fault_trigger,
61	.run = gcs_op_fault_signal,
62};