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-rw-r--r--tools/testing/selftests/arm64/signal/.gitignore4
-rw-r--r--tools/testing/selftests/arm64/signal/Makefile28
-rw-r--r--tools/testing/selftests/arm64/signal/README59
-rw-r--r--tools/testing/selftests/arm64/signal/signals.S64
-rw-r--r--tools/testing/selftests/arm64/signal/test_signals.c29
-rw-r--r--tools/testing/selftests/arm64/signal/test_signals.h102
-rw-r--r--tools/testing/selftests/arm64/signal/test_signals_utils.c334
-rw-r--r--tools/testing/selftests/arm64/signal/test_signals_utils.h120
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_magic.c52
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size.c77
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size_for_magic0.c46
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_duplicated_fpsimd.c50
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c37
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_missing_fpsimd.c50
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c31
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_daif_bits.c35
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1h.c15
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1t.c15
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2h.c15
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2t.c15
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3h.c15
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3t.c15
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_template.h28
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/testcases.c196
-rw-r--r--tools/testing/selftests/arm64/signal/testcases/testcases.h104
25 files changed, 1536 insertions, 0 deletions
diff --git a/tools/testing/selftests/arm64/signal/.gitignore b/tools/testing/selftests/arm64/signal/.gitignore
new file mode 100644
index 000000000..78c902045
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/.gitignore
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+mangle_*
+fake_sigreturn_*
+!*.[ch]
diff --git a/tools/testing/selftests/arm64/signal/Makefile b/tools/testing/selftests/arm64/signal/Makefile
new file mode 100644
index 000000000..ac4ad0005
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/Makefile
@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2019 ARM Limited
+
+# Additional include paths needed by kselftest.h and local headers
+CFLAGS += -D_GNU_SOURCE -std=gnu99 -I.
+
+SRCS := $(filter-out testcases/testcases.c,$(wildcard testcases/*.c))
+PROGS := $(patsubst %.c,%,$(SRCS))
+
+# Generated binaries to be installed by top KSFT script
+TEST_GEN_PROGS := $(notdir $(PROGS))
+
+# Get Kernel headers installed and use them.
+KSFT_KHDR_INSTALL := 1
+
+# Including KSFT lib.mk here will also mangle the TEST_GEN_PROGS list
+# to account for any OUTPUT target-dirs optionally provided by
+# the toplevel makefile
+include ../../lib.mk
+
+$(TEST_GEN_PROGS): $(PROGS)
+ cp $(PROGS) $(OUTPUT)/
+
+# Common test-unit targets to build common-layout test-cases executables
+# Needs secondary expansion to properly include the testcase c-file in pre-reqs
+.SECONDEXPANSION:
+$(PROGS): test_signals.c test_signals_utils.c testcases/testcases.c signals.S $$@.c test_signals.h test_signals_utils.h testcases/testcases.h
+ $(CC) $(CFLAGS) $^ -o $@
diff --git a/tools/testing/selftests/arm64/signal/README b/tools/testing/selftests/arm64/signal/README
new file mode 100644
index 000000000..967a531b2
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/README
@@ -0,0 +1,59 @@
+KSelfTest arm64/signal/
+=======================
+
+Signals Tests
++++++++++++++
+
+- Tests are built around a common main compilation unit: such shared main
+ enforces a standard sequence of operations needed to perform a single
+ signal-test (setup/trigger/run/result/cleanup)
+
+- The above mentioned ops are configurable on a test-by-test basis: each test
+ is described (and configured) using the descriptor signals.h::struct tdescr
+
+- Each signal testcase is compiled into its own executable: a separate
+ executable is used for each test since many tests complete successfully
+ by receiving some kind of fatal signal from the Kernel, so it's safer
+ to run each test unit in its own standalone process, so as to start each
+ test from a clean slate.
+
+- New tests can be simply defined in testcases/ dir providing a proper struct
+ tdescr overriding all the defaults we wish to change (as of now providing a
+ custom run method is mandatory though)
+
+- Signals' test-cases hereafter defined belong currently to two
+ principal families:
+
+ - 'mangle_' tests: a real signal (SIGUSR1) is raised and used as a trigger
+ and then the test case code modifies the signal frame from inside the
+ signal handler itself.
+
+ - 'fake_sigreturn_' tests: a brand new custom artificial sigframe structure
+ is placed on the stack and a sigreturn syscall is called to simulate a
+ real signal return. This kind of tests does not use a trigger usually and
+ they are just fired using some simple included assembly trampoline code.
+
+ - Most of these tests are successfully passing if the process gets killed by
+ some fatal signal: usually SIGSEGV or SIGBUS. Since while writing this
+ kind of tests it is extremely easy in fact to end-up injecting other
+ unrelated SEGV bugs in the testcases, it becomes extremely tricky to
+ be really sure that the tests are really addressing what they are meant
+ to address and they are not instead falling apart due to unplanned bugs
+ in the test code.
+ In order to alleviate the misery of the life of such test-developer, a few
+ helpers are provided:
+
+ - a couple of ASSERT_BAD/GOOD_CONTEXT() macros to easily parse a ucontext_t
+ and verify if it is indeed GOOD or BAD (depending on what we were
+ expecting), using the same logic/perspective as in the arm64 Kernel signals
+ routines.
+
+ - a sanity mechanism to be used in 'fake_sigreturn_'-alike tests: enabled by
+ default it takes care to verify that the test-execution had at least
+ successfully progressed up to the stage of triggering the fake sigreturn
+ call.
+
+ In both cases test results are expected in terms of:
+ - some fatal signal sent by the Kernel to the test process
+ or
+ - analyzing some final regs state
diff --git a/tools/testing/selftests/arm64/signal/signals.S b/tools/testing/selftests/arm64/signal/signals.S
new file mode 100644
index 000000000..9f8c1aefc
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/signals.S
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 ARM Limited */
+
+#include <asm/unistd.h>
+
+.section .rodata, "a"
+call_fmt:
+ .asciz "Calling sigreturn with fake sigframe sized:%zd at SP @%08lX\n"
+
+.text
+
+.globl fake_sigreturn
+
+/* fake_sigreturn x0:&sigframe, x1:sigframe_size, x2:misalign_bytes */
+fake_sigreturn:
+ stp x29, x30, [sp, #-16]!
+ mov x29, sp
+
+ mov x20, x0
+ mov x21, x1
+ mov x22, x2
+
+ /* create space on the stack for fake sigframe 16 bytes-aligned */
+ add x0, x21, x22
+ add x0, x0, #15
+ bic x0, x0, #15 /* round_up(sigframe_size + misalign_bytes, 16) */
+ sub sp, sp, x0
+ add x23, sp, x22 /* new sigframe base with misaligment if any */
+
+ ldr x0, =call_fmt
+ mov x1, x21
+ mov x2, x23
+ bl printf
+
+ /* memcpy the provided content, while still keeping SP aligned */
+ mov x0, x23
+ mov x1, x20
+ mov x2, x21
+ bl memcpy
+
+ /*
+ * Here saving a last minute SP to current->token acts as a marker:
+ * if we got here, we are successfully faking a sigreturn; in other
+ * words we are sure no bad fatal signal has been raised till now
+ * for unrelated reasons, so we should consider the possibly observed
+ * fatal signal like SEGV coming from Kernel restore_sigframe() and
+ * triggered as expected from our test-case.
+ * For simplicity this assumes that current field 'token' is laid out
+ * as first in struct tdescr
+ */
+ ldr x0, current
+ str x23, [x0]
+ /* finally move SP to misaligned address...if any requested */
+ mov sp, x23
+
+ mov x8, #__NR_rt_sigreturn
+ svc #0
+
+ /*
+ * Above sigreturn should not return...looping here leads to a timeout
+ * and ensure proper and clean test failure, instead of jumping around
+ * on a potentially corrupted stack.
+ */
+ b .
diff --git a/tools/testing/selftests/arm64/signal/test_signals.c b/tools/testing/selftests/arm64/signal/test_signals.c
new file mode 100644
index 000000000..416b1ff43
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Generic test wrapper for arm64 signal tests.
+ *
+ * Each test provides its own tde struct tdescr descriptor to link with
+ * this wrapper. Framework provides common helpers.
+ */
+#include <kselftest.h>
+
+#include "test_signals.h"
+#include "test_signals_utils.h"
+
+struct tdescr *current;
+
+int main(int argc, char *argv[])
+{
+ current = &tde;
+
+ ksft_print_msg("%s :: %s\n", current->name, current->descr);
+ if (test_setup(current) && test_init(current)) {
+ test_run(current);
+ test_cleanup(current);
+ }
+ test_result(current);
+
+ return current->result;
+}
diff --git a/tools/testing/selftests/arm64/signal/test_signals.h b/tools/testing/selftests/arm64/signal/test_signals.h
new file mode 100644
index 000000000..ebe8694db
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals.h
@@ -0,0 +1,102 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 ARM Limited */
+
+#ifndef __TEST_SIGNALS_H__
+#define __TEST_SIGNALS_H__
+
+#include <signal.h>
+#include <stdbool.h>
+#include <ucontext.h>
+
+/*
+ * Using ARCH specific and sanitized Kernel headers installed by KSFT
+ * framework since we asked for it by setting flag KSFT_KHDR_INSTALL
+ * in our Makefile.
+ */
+#include <asm/ptrace.h>
+#include <asm/hwcap.h>
+
+#define __stringify_1(x...) #x
+#define __stringify(x...) __stringify_1(x)
+
+#define get_regval(regname, out) \
+{ \
+ asm volatile("mrs %0, " __stringify(regname) \
+ : "=r" (out) \
+ : \
+ : "memory"); \
+}
+
+/*
+ * Feature flags used in tdescr.feats_required to specify
+ * any feature by the test
+ */
+enum {
+ FSSBS_BIT,
+ FSVE_BIT,
+ FMAX_END
+};
+
+#define FEAT_SSBS (1UL << FSSBS_BIT)
+#define FEAT_SVE (1UL << FSVE_BIT)
+
+/*
+ * A descriptor used to describe and configure a test case.
+ * Fields with a non-trivial meaning are described inline in the following.
+ */
+struct tdescr {
+ /* KEEP THIS FIELD FIRST for easier lookup from assembly */
+ void *token;
+ /* when disabled token based sanity checking is skipped in handler */
+ bool sanity_disabled;
+ /* just a name for the test-case; manadatory field */
+ char *name;
+ char *descr;
+ unsigned long feats_required;
+ /* bitmask of effectively supported feats: populated at run-time */
+ unsigned long feats_supported;
+ bool initialized;
+ unsigned int minsigstksz;
+ /* signum used as a test trigger. Zero if no trigger-signal is used */
+ int sig_trig;
+ /*
+ * signum considered as a successful test completion.
+ * Zero when no signal is expected on success
+ */
+ int sig_ok;
+ /* signum expected on unsupported CPU features. */
+ int sig_unsupp;
+ /* a timeout in second for test completion */
+ unsigned int timeout;
+ bool triggered;
+ bool pass;
+ unsigned int result;
+ /* optional sa_flags for the installed handler */
+ int sa_flags;
+ ucontext_t saved_uc;
+ /* used by get_current_ctx() */
+ size_t live_sz;
+ ucontext_t *live_uc;
+ volatile sig_atomic_t live_uc_valid;
+ /* optional test private data */
+ void *priv;
+
+ /* a custom setup: called alternatively to default_setup */
+ int (*setup)(struct tdescr *td);
+ /* a custom init: called by default test init after test_setup */
+ bool (*init)(struct tdescr *td);
+ /* a custom cleanup function called before test exits */
+ void (*cleanup)(struct tdescr *td);
+ /* an optional function to be used as a trigger for starting test */
+ int (*trigger)(struct tdescr *td);
+ /*
+ * the actual test-core: invoked differently depending on the
+ * presence of the trigger function above; this is mandatory
+ */
+ int (*run)(struct tdescr *td, siginfo_t *si, ucontext_t *uc);
+ /* an optional function for custom results' processing */
+ void (*check_result)(struct tdescr *td);
+};
+
+extern struct tdescr tde;
+#endif
diff --git a/tools/testing/selftests/arm64/signal/test_signals_utils.c b/tools/testing/selftests/arm64/signal/test_signals_utils.c
new file mode 100644
index 000000000..22722abc9
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals_utils.c
@@ -0,0 +1,334 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2019 ARM Limited */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <string.h>
+#include <unistd.h>
+#include <assert.h>
+#include <sys/auxv.h>
+#include <linux/auxvec.h>
+#include <ucontext.h>
+
+#include <asm/unistd.h>
+
+#include <kselftest.h>
+
+#include "test_signals.h"
+#include "test_signals_utils.h"
+#include "testcases/testcases.h"
+
+
+extern struct tdescr *current;
+
+static int sig_copyctx = SIGTRAP;
+
+static char const *const feats_names[FMAX_END] = {
+ " SSBS ",
+ " SVE ",
+};
+
+#define MAX_FEATS_SZ 128
+static char feats_string[MAX_FEATS_SZ];
+
+static inline char *feats_to_string(unsigned long feats)
+{
+ size_t flen = MAX_FEATS_SZ - 1;
+
+ for (int i = 0; i < FMAX_END; i++) {
+ if (feats & (1UL << i)) {
+ size_t tlen = strlen(feats_names[i]);
+
+ assert(flen > tlen);
+ flen -= tlen;
+ strncat(feats_string, feats_names[i], flen);
+ }
+ }
+
+ return feats_string;
+}
+
+static void unblock_signal(int signum)
+{
+ sigset_t sset;
+
+ sigemptyset(&sset);
+ sigaddset(&sset, signum);
+ sigprocmask(SIG_UNBLOCK, &sset, NULL);
+}
+
+static void default_result(struct tdescr *td, bool force_exit)
+{
+ if (td->result == KSFT_SKIP) {
+ fprintf(stderr, "==>> completed. SKIP.\n");
+ } else if (td->pass) {
+ fprintf(stderr, "==>> completed. PASS(1)\n");
+ td->result = KSFT_PASS;
+ } else {
+ fprintf(stdout, "==>> completed. FAIL(0)\n");
+ td->result = KSFT_FAIL;
+ }
+
+ if (force_exit)
+ exit(td->result);
+}
+
+/*
+ * The following handle_signal_* helpers are used by main default_handler
+ * and are meant to return true when signal is handled successfully:
+ * when false is returned instead, it means that the signal was somehow
+ * unexpected in that context and it was NOT handled; default_handler will
+ * take care of such unexpected situations.
+ */
+
+static bool handle_signal_unsupported(struct tdescr *td,
+ siginfo_t *si, void *uc)
+{
+ if (feats_ok(td))
+ return false;
+
+ /* Mangling PC to avoid loops on original SIGILL */
+ ((ucontext_t *)uc)->uc_mcontext.pc += 4;
+
+ if (!td->initialized) {
+ fprintf(stderr,
+ "Got SIG_UNSUPP @test_init. Ignore.\n");
+ } else {
+ fprintf(stderr,
+ "-- RX SIG_UNSUPP on unsupported feat...OK\n");
+ td->pass = 1;
+ default_result(current, 1);
+ }
+
+ return true;
+}
+
+static bool handle_signal_trigger(struct tdescr *td,
+ siginfo_t *si, void *uc)
+{
+ td->triggered = 1;
+ /* ->run was asserted NON-NULL in test_setup() already */
+ td->run(td, si, uc);
+
+ return true;
+}
+
+static bool handle_signal_ok(struct tdescr *td,
+ siginfo_t *si, void *uc)
+{
+ /*
+ * it's a bug in the test code when this assert fail:
+ * if sig_trig was defined, it must have been used before getting here.
+ */
+ assert(!td->sig_trig || td->triggered);
+ fprintf(stderr,
+ "SIG_OK -- SP:0x%llX si_addr@:%p si_code:%d token@:%p offset:%ld\n",
+ ((ucontext_t *)uc)->uc_mcontext.sp,
+ si->si_addr, si->si_code, td->token, td->token - si->si_addr);
+ /*
+ * fake_sigreturn tests, which have sanity_enabled=1, set, at the very
+ * last time, the token field to the SP address used to place the fake
+ * sigframe: so token==0 means we never made it to the end,
+ * segfaulting well-before, and the test is possibly broken.
+ */
+ if (!td->sanity_disabled && !td->token) {
+ fprintf(stdout,
+ "current->token ZEROED...test is probably broken!\n");
+ abort();
+ }
+ /*
+ * Trying to narrow down the SEGV to the ones generated by Kernel itself
+ * via arm64_notify_segfault(). This is a best-effort check anyway, and
+ * the si_code check may need to change if this aspect of the kernel
+ * ABI changes.
+ */
+ if (td->sig_ok == SIGSEGV && si->si_code != SEGV_ACCERR) {
+ fprintf(stdout,
+ "si_code != SEGV_ACCERR...test is probably broken!\n");
+ abort();
+ }
+ td->pass = 1;
+ /*
+ * Some tests can lead to SEGV loops: in such a case we want to
+ * terminate immediately exiting straight away; some others are not
+ * supposed to outlive the signal handler code, due to the content of
+ * the fake sigframe which caused the signal itself.
+ */
+ default_result(current, 1);
+
+ return true;
+}
+
+static bool handle_signal_copyctx(struct tdescr *td,
+ siginfo_t *si, void *uc)
+{
+ /* Mangling PC to avoid loops on original BRK instr */
+ ((ucontext_t *)uc)->uc_mcontext.pc += 4;
+ memcpy(td->live_uc, uc, td->live_sz);
+ ASSERT_GOOD_CONTEXT(td->live_uc);
+ td->live_uc_valid = 1;
+ fprintf(stderr,
+ "GOOD CONTEXT grabbed from sig_copyctx handler\n");
+
+ return true;
+}
+
+static void default_handler(int signum, siginfo_t *si, void *uc)
+{
+ if (current->sig_unsupp && signum == current->sig_unsupp &&
+ handle_signal_unsupported(current, si, uc)) {
+ fprintf(stderr, "Handled SIG_UNSUPP\n");
+ } else if (current->sig_trig && signum == current->sig_trig &&
+ handle_signal_trigger(current, si, uc)) {
+ fprintf(stderr, "Handled SIG_TRIG\n");
+ } else if (current->sig_ok && signum == current->sig_ok &&
+ handle_signal_ok(current, si, uc)) {
+ fprintf(stderr, "Handled SIG_OK\n");
+ } else if (signum == sig_copyctx && current->live_uc &&
+ handle_signal_copyctx(current, si, uc)) {
+ fprintf(stderr, "Handled SIG_COPYCTX\n");
+ } else {
+ if (signum == SIGALRM && current->timeout) {
+ fprintf(stderr, "-- Timeout !\n");
+ } else {
+ fprintf(stderr,
+ "-- RX UNEXPECTED SIGNAL: %d\n", signum);
+ }
+ default_result(current, 1);
+ }
+}
+
+static int default_setup(struct tdescr *td)
+{
+ struct sigaction sa;
+
+ sa.sa_sigaction = default_handler;
+ sa.sa_flags = SA_SIGINFO | SA_RESTART;
+ sa.sa_flags |= td->sa_flags;
+ sigemptyset(&sa.sa_mask);
+ /* uncatchable signals naturally skipped ... */
+ for (int sig = 1; sig < 32; sig++)
+ sigaction(sig, &sa, NULL);
+ /*
+ * RT Signals default disposition is Term but they cannot be
+ * generated by the Kernel in response to our tests; so just catch
+ * them all and report them as UNEXPECTED signals.
+ */
+ for (int sig = SIGRTMIN; sig <= SIGRTMAX; sig++)
+ sigaction(sig, &sa, NULL);
+
+ /* just in case...unblock explicitly all we need */
+ if (td->sig_trig)
+ unblock_signal(td->sig_trig);
+ if (td->sig_ok)
+ unblock_signal(td->sig_ok);
+ if (td->sig_unsupp)
+ unblock_signal(td->sig_unsupp);
+
+ if (td->timeout) {
+ unblock_signal(SIGALRM);
+ alarm(td->timeout);
+ }
+ fprintf(stderr, "Registered handlers for all signals.\n");
+
+ return 1;
+}
+
+static inline int default_trigger(struct tdescr *td)
+{
+ return !raise(td->sig_trig);
+}
+
+int test_init(struct tdescr *td)
+{
+ if (td->sig_trig == sig_copyctx) {
+ fprintf(stdout,
+ "Signal %d is RESERVED, cannot be used as a trigger. Aborting\n",
+ sig_copyctx);
+ return 0;
+ }
+ /* just in case */
+ unblock_signal(sig_copyctx);
+
+ td->minsigstksz = getauxval(AT_MINSIGSTKSZ);
+ if (!td->minsigstksz)
+ td->minsigstksz = MINSIGSTKSZ;
+ fprintf(stderr, "Detected MINSTKSIGSZ:%d\n", td->minsigstksz);
+
+ if (td->feats_required) {
+ td->feats_supported = 0;
+ /*
+ * Checking for CPU required features using both the
+ * auxval and the arm64 MRS Emulation to read sysregs.
+ */
+ if (getauxval(AT_HWCAP) & HWCAP_SSBS)
+ td->feats_supported |= FEAT_SSBS;
+ if (getauxval(AT_HWCAP) & HWCAP_SVE)
+ td->feats_supported |= FEAT_SVE;
+ if (feats_ok(td)) {
+ fprintf(stderr,
+ "Required Features: [%s] supported\n",
+ feats_to_string(td->feats_required &
+ td->feats_supported));
+ } else {
+ fprintf(stderr,
+ "Required Features: [%s] NOT supported\n",
+ feats_to_string(td->feats_required &
+ ~td->feats_supported));
+ td->result = KSFT_SKIP;
+ return 0;
+ }
+ }
+
+ /* Perform test specific additional initialization */
+ if (td->init && !td->init(td)) {
+ fprintf(stderr, "FAILED Testcase initialization.\n");
+ return 0;
+ }
+ td->initialized = 1;
+ fprintf(stderr, "Testcase initialized.\n");
+
+ return 1;
+}
+
+int test_setup(struct tdescr *td)
+{
+ /* assert core invariants symptom of a rotten testcase */
+ assert(current);
+ assert(td);
+ assert(td->name);
+ assert(td->run);
+
+ /* Default result is FAIL if test setup fails */
+ td->result = KSFT_FAIL;
+ if (td->setup)
+ return td->setup(td);
+ else
+ return default_setup(td);
+}
+
+int test_run(struct tdescr *td)
+{
+ if (td->sig_trig) {
+ if (td->trigger)
+ return td->trigger(td);
+ else
+ return default_trigger(td);
+ } else {
+ return td->run(td, NULL, NULL);
+ }
+}
+
+void test_result(struct tdescr *td)
+{
+ if (td->initialized && td->result != KSFT_SKIP && td->check_result)
+ td->check_result(td);
+ default_result(td, 0);
+}
+
+void test_cleanup(struct tdescr *td)
+{
+ if (td->cleanup)
+ td->cleanup(td);
+}
diff --git a/tools/testing/selftests/arm64/signal/test_signals_utils.h b/tools/testing/selftests/arm64/signal/test_signals_utils.h
new file mode 100644
index 000000000..6772b5c8d
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals_utils.h
@@ -0,0 +1,120 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 ARM Limited */
+
+#ifndef __TEST_SIGNALS_UTILS_H__
+#define __TEST_SIGNALS_UTILS_H__
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "test_signals.h"
+
+int test_init(struct tdescr *td);
+int test_setup(struct tdescr *td);
+void test_cleanup(struct tdescr *td);
+int test_run(struct tdescr *td);
+void test_result(struct tdescr *td);
+
+static inline bool feats_ok(struct tdescr *td)
+{
+ return (td->feats_required & td->feats_supported) == td->feats_required;
+}
+
+/*
+ * Obtaining a valid and full-blown ucontext_t from userspace is tricky:
+ * libc getcontext does() not save all the regs and messes with some of
+ * them (pstate value in particular is not reliable).
+ *
+ * Here we use a service signal to grab the ucontext_t from inside a
+ * dedicated signal handler, since there, it is populated by Kernel
+ * itself in setup_sigframe(). The grabbed context is then stored and
+ * made available in td->live_uc.
+ *
+ * As service-signal is used a SIGTRAP induced by a 'brk' instruction,
+ * because here we have to avoid syscalls to trigger the signal since
+ * they would cause any SVE sigframe content (if any) to be removed.
+ *
+ * Anyway this function really serves a dual purpose:
+ *
+ * 1. grab a valid sigcontext into td->live_uc for result analysis: in
+ * such case it returns 1.
+ *
+ * 2. detect if, somehow, a previously grabbed live_uc context has been
+ * used actively with a sigreturn: in such a case the execution would have
+ * magically resumed in the middle of this function itself (seen_already==1):
+ * in such a case return 0, since in fact we have not just simply grabbed
+ * the context.
+ *
+ * This latter case is useful to detect when a fake_sigreturn test-case has
+ * unexpectedly survived without hitting a SEGV.
+ *
+ * Note that the case of runtime dynamically sized sigframes (like in SVE
+ * context) is still NOT addressed: sigframe size is supposed to be fixed
+ * at sizeof(ucontext_t).
+ */
+static __always_inline bool get_current_context(struct tdescr *td,
+ ucontext_t *dest_uc)
+{
+ static volatile bool seen_already;
+
+ assert(td && dest_uc);
+ /* it's a genuine invocation..reinit */
+ seen_already = 0;
+ td->live_uc_valid = 0;
+ td->live_sz = sizeof(*dest_uc);
+ memset(dest_uc, 0x00, td->live_sz);
+ td->live_uc = dest_uc;
+ /*
+ * Grab ucontext_t triggering a SIGTRAP.
+ *
+ * Note that:
+ * - live_uc_valid is declared volatile sig_atomic_t in
+ * struct tdescr since it will be changed inside the
+ * sig_copyctx handler
+ * - the additional 'memory' clobber is there to avoid possible
+ * compiler's assumption on live_uc_valid and the content
+ * pointed by dest_uc, which are all changed inside the signal
+ * handler
+ * - BRK causes a debug exception which is handled by the Kernel
+ * and finally causes the SIGTRAP signal to be delivered to this
+ * test thread. Since such delivery happens on the ret_to_user()
+ * /do_notify_resume() debug exception return-path, we are sure
+ * that the registered SIGTRAP handler has been run to completion
+ * before the execution path is restored here: as a consequence
+ * we can be sure that the volatile sig_atomic_t live_uc_valid
+ * carries a meaningful result. Being in a single thread context
+ * we'll also be sure that any access to memory modified by the
+ * handler (namely ucontext_t) will be visible once returned.
+ * - note that since we are using a breakpoint instruction here
+ * to cause a SIGTRAP, the ucontext_t grabbed from the signal
+ * handler would naturally contain a PC pointing exactly to this
+ * BRK line, which means that, on return from the signal handler,
+ * or if we place the ucontext_t on the stack to fake a sigreturn,
+ * we'll end up in an infinite loop of BRK-SIGTRAP-handler.
+ * For this reason we take care to artificially move forward the
+ * PC to the next instruction while inside the signal handler.
+ */
+ asm volatile ("brk #666"
+ : "+m" (*dest_uc)
+ :
+ : "memory");
+
+ /*
+ * If we get here with seen_already==1 it implies the td->live_uc
+ * context has been used to get back here....this probably means
+ * a test has failed to cause a SEGV...anyway live_uc does not
+ * point to a just acquired copy of ucontext_t...so return 0
+ */
+ if (seen_already) {
+ fprintf(stdout,
+ "Unexpected successful sigreturn detected: live_uc is stale !\n");
+ return 0;
+ }
+ seen_already = 1;
+
+ return td->live_uc_valid;
+}
+
+int fake_sigreturn(void *sigframe, size_t sz, int misalign_bytes);
+#endif
diff --git a/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_magic.c b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_magic.c
new file mode 100644
index 000000000..8dc600a7d
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_magic.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Place a fake sigframe on the stack including a BAD Unknown magic
+ * record: 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_bad_magic_run(struct tdescr *td,
+ siginfo_t *si, ucontext_t *uc)
+{
+ struct _aarch64_ctx *shead = GET_SF_RESV_HEAD(sf), *head;
+
+ /* just to fill the ucontext_t with something real */
+ if (!get_current_context(td, &sf.uc))
+ return 1;
+
+ /* need at least 2*HDR_SZ space: KSFT_BAD_MAGIC + terminator. */
+ head = get_starting_head(shead, HDR_SZ * 2, GET_SF_RESV_SIZE(sf), NULL);
+ if (!head)
+ return 0;
+
+ /*
+ * use a well known NON existent bad magic...something
+ * we should pretty sure won't be ever defined in Kernel
+ */
+ head->magic = KSFT_BAD_MAGIC;
+ head->size = HDR_SZ;
+ write_terminator_record(GET_RESV_NEXT_HEAD(head));
+
+ ASSERT_BAD_CONTEXT(&sf.uc);
+ fake_sigreturn(&sf, sizeof(sf), 0);
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .name = "FAKE_SIGRETURN_BAD_MAGIC",
+ .descr = "Trigger a sigreturn with a sigframe with a bad magic",
+ .sig_ok = SIGSEGV,
+ .timeout = 3,
+ .run = fake_sigreturn_bad_magic_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size.c b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size.c
new file mode 100644
index 000000000..b3c362100
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Place a fake sigframe on the stack including a bad record overflowing
+ * the __reserved space: 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;
+
+#define MIN_SZ_ALIGN 16
+
+static int fake_sigreturn_bad_size_run(struct tdescr *td,
+ siginfo_t *si, ucontext_t *uc)
+{
+ size_t resv_sz, need_sz, offset;
+ struct _aarch64_ctx *shead = GET_SF_RESV_HEAD(sf), *head;
+
+ /* just to fill the ucontext_t with something real */
+ if (!get_current_context(td, &sf.uc))
+ return 1;
+
+ resv_sz = GET_SF_RESV_SIZE(sf);
+ /* at least HDR_SZ + bad sized esr_context needed */
+ need_sz = sizeof(struct esr_context) + HDR_SZ;
+ head = get_starting_head(shead, need_sz, resv_sz, &offset);
+ if (!head)
+ return 0;
+
+ /*
+ * Use an esr_context to build a fake header with a
+ * size greater then the free __reserved area minus HDR_SZ;
+ * using ESR_MAGIC here since it is not checked for size nor
+ * is limited to one instance.
+ *
+ * At first inject an additional normal esr_context
+ */
+ head->magic = ESR_MAGIC;
+ head->size = sizeof(struct esr_context);
+ /* and terminate properly */
+ write_terminator_record(GET_RESV_NEXT_HEAD(head));
+ ASSERT_GOOD_CONTEXT(&sf.uc);
+
+ /*
+ * now mess with fake esr_context size: leaving less space than
+ * needed while keeping size value 16-aligned
+ *
+ * It must trigger a SEGV from Kernel on:
+ *
+ * resv_sz - offset < sizeof(*head)
+ */
+ /* at first set the maximum good 16-aligned size */
+ head->size = (resv_sz - offset - need_sz + MIN_SZ_ALIGN) & ~0xfUL;
+ /* plus a bit more of 16-aligned sized stuff */
+ head->size += MIN_SZ_ALIGN;
+ /* and terminate properly */
+ write_terminator_record(GET_RESV_NEXT_HEAD(head));
+ ASSERT_BAD_CONTEXT(&sf.uc);
+ fake_sigreturn(&sf, sizeof(sf), 0);
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .name = "FAKE_SIGRETURN_BAD_SIZE",
+ .descr = "Triggers a sigreturn with a overrun __reserved area",
+ .sig_ok = SIGSEGV,
+ .timeout = 3,
+ .run = fake_sigreturn_bad_size_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size_for_magic0.c b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size_for_magic0.c
new file mode 100644
index 000000000..a44b88bfc
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_bad_size_for_magic0.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Place a fake sigframe on the stack including a badly sized terminator
+ * record: 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_bad_size_for_magic0_run(struct tdescr *td,
+ siginfo_t *si, ucontext_t *uc)
+{
+ struct _aarch64_ctx *shead = GET_SF_RESV_HEAD(sf), *head;
+
+ /* just to fill the ucontext_t with something real */
+ if (!get_current_context(td, &sf.uc))
+ return 1;
+
+ /* at least HDR_SZ for the badly sized terminator. */
+ head = get_starting_head(shead, HDR_SZ, GET_SF_RESV_SIZE(sf), NULL);
+ if (!head)
+ return 0;
+
+ head->magic = 0;
+ head->size = HDR_SZ;
+ ASSERT_BAD_CONTEXT(&sf.uc);
+ fake_sigreturn(&sf, sizeof(sf), 0);
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .name = "FAKE_SIGRETURN_BAD_SIZE_FOR_TERMINATOR",
+ .descr = "Trigger a sigreturn using non-zero size terminator",
+ .sig_ok = SIGSEGV,
+ .timeout = 3,
+ .run = fake_sigreturn_bad_size_for_magic0_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_duplicated_fpsimd.c b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_duplicated_fpsimd.c
new file mode 100644
index 000000000..afe8915f0
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_duplicated_fpsimd.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Place a fake sigframe on the stack including an additional FPSIMD
+ * record: 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_duplicated_fpsimd_run(struct tdescr *td,
+ siginfo_t *si, ucontext_t *uc)
+{
+ struct _aarch64_ctx *shead = GET_SF_RESV_HEAD(sf), *head;
+
+ /* just to fill the ucontext_t with something real */
+ if (!get_current_context(td, &sf.uc))
+ return 1;
+
+ head = get_starting_head(shead, sizeof(struct fpsimd_context) + HDR_SZ,
+ GET_SF_RESV_SIZE(sf), NULL);
+ if (!head)
+ return 0;
+
+ /* Add a spurious fpsimd_context */
+ head->magic = FPSIMD_MAGIC;
+ head->size = sizeof(struct fpsimd_context);
+ /* and terminate */
+ write_terminator_record(GET_RESV_NEXT_HEAD(head));
+
+ ASSERT_BAD_CONTEXT(&sf.uc);
+ fake_sigreturn(&sf, sizeof(sf), 0);
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .name = "FAKE_SIGRETURN_DUPLICATED_FPSIMD",
+ .descr = "Triggers a sigreturn including two fpsimd_context",
+ .sig_ok = SIGSEGV,
+ .timeout = 3,
+ .run = fake_sigreturn_duplicated_fpsimd_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c
new file mode 100644
index 000000000..1e089e66f
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c
@@ -0,0 +1,37 @@
+// 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,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_missing_fpsimd.c b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_missing_fpsimd.c
new file mode 100644
index 000000000..08ecd8073
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_missing_fpsimd.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Place a fake sigframe on the stack missing the mandatory FPSIMD
+ * record: on sigreturn Kernel must spot this attempt and the test
+ * case is expected to be terminated via SEGV.
+ */
+
+#include <stdio.h>
+#include <signal.h>
+#include <ucontext.h>
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+struct fake_sigframe sf;
+
+static int fake_sigreturn_missing_fpsimd_run(struct tdescr *td,
+ siginfo_t *si, ucontext_t *uc)
+{
+ size_t resv_sz, offset;
+ struct _aarch64_ctx *head = GET_SF_RESV_HEAD(sf);
+
+ /* just to fill the ucontext_t with something real */
+ if (!get_current_context(td, &sf.uc))
+ return 1;
+
+ resv_sz = GET_SF_RESV_SIZE(sf);
+ head = get_header(head, FPSIMD_MAGIC, resv_sz, &offset);
+ if (head && resv_sz - offset >= HDR_SZ) {
+ fprintf(stderr, "Mangling template header. Spare space:%zd\n",
+ resv_sz - offset);
+ /* Just overwrite fpsmid_context */
+ write_terminator_record(head);
+
+ ASSERT_BAD_CONTEXT(&sf.uc);
+ fake_sigreturn(&sf, sizeof(sf), 0);
+ }
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .name = "FAKE_SIGRETURN_MISSING_FPSIMD",
+ .descr = "Triggers a sigreturn with a missing fpsimd_context",
+ .sig_ok = SIGSEGV,
+ .timeout = 3,
+ .run = fake_sigreturn_missing_fpsimd_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c
new file mode 100644
index 000000000..2cb118b0b
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the execution state bit: this attempt must be spotted by Kernel and
+ * the test case is expected to be terminated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+static int mangle_invalid_pstate_run(struct tdescr *td, siginfo_t *si,
+ ucontext_t *uc)
+{
+ ASSERT_GOOD_CONTEXT(uc);
+
+ /* This config should trigger a SIGSEGV by Kernel */
+ uc->uc_mcontext.pstate ^= PSR_MODE32_BIT;
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .sanity_disabled = true,
+ .name = "MANGLE_PSTATE_INVALID_STATE_TOGGLE",
+ .descr = "Mangling uc_mcontext with INVALID STATE_TOGGLE",
+ .sig_trig = SIGUSR1,
+ .sig_ok = SIGSEGV,
+ .run = mangle_invalid_pstate_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_daif_bits.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_daif_bits.c
new file mode 100644
index 000000000..434b82597
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_daif_bits.c
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, mangling the
+ * DAIF bits in an illegal manner: this attempt must be spotted by Kernel
+ * and the test case is expected to be terminated via SEGV.
+ *
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+static int mangle_invalid_pstate_run(struct tdescr *td, siginfo_t *si,
+ ucontext_t *uc)
+{
+ ASSERT_GOOD_CONTEXT(uc);
+
+ /*
+ * This config should trigger a SIGSEGV by Kernel when it checks
+ * the sigframe consistency in valid_user_regs() routine.
+ */
+ uc->uc_mcontext.pstate |= PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT;
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .sanity_disabled = true,
+ .name = "MANGLE_PSTATE_INVALID_DAIF_BITS",
+ .descr = "Mangling uc_mcontext with INVALID DAIF_BITS",
+ .sig_trig = SIGUSR1,
+ .sig_ok = SIGSEGV,
+ .run = mangle_invalid_pstate_run,
+};
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1h.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1h.c
new file mode 100644
index 000000000..95f821abd
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1h.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the mode bit to escalate exception level: this attempt must be spotted
+ * by Kernel and the test case is expected to be termninated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#include "mangle_pstate_invalid_mode_template.h"
+
+DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(1h);
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1t.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1t.c
new file mode 100644
index 000000000..cc222d8a6
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el1t.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the mode bit to escalate exception level: this attempt must be spotted
+ * by Kernel and the test case is expected to be termninated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#include "mangle_pstate_invalid_mode_template.h"
+
+DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(1t);
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2h.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2h.c
new file mode 100644
index 000000000..2188add7d
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2h.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the mode bit to escalate exception level: this attempt must be spotted
+ * by Kernel and the test case is expected to be termninated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#include "mangle_pstate_invalid_mode_template.h"
+
+DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(2h);
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2t.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2t.c
new file mode 100644
index 000000000..df32dd5a4
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el2t.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the mode bit to escalate exception level: this attempt must be spotted
+ * by Kernel and the test case is expected to be termninated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#include "mangle_pstate_invalid_mode_template.h"
+
+DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(2t);
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3h.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3h.c
new file mode 100644
index 000000000..9e6829b7e
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3h.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the mode bit to escalate exception level: this attempt must be spotted
+ * by Kernel and the test case is expected to be termninated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#include "mangle_pstate_invalid_mode_template.h"
+
+DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(3h);
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3t.c b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3t.c
new file mode 100644
index 000000000..5685a4f10
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_el3t.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Try to mangle the ucontext from inside a signal handler, toggling
+ * the mode bit to escalate exception level: this attempt must be spotted
+ * by Kernel and the test case is expected to be termninated via SEGV.
+ */
+
+#include "test_signals_utils.h"
+#include "testcases.h"
+
+#include "mangle_pstate_invalid_mode_template.h"
+
+DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(3t);
diff --git a/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_template.h b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_template.h
new file mode 100644
index 000000000..f5bf1804d
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_mode_template.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 ARM Limited
+ *
+ * Utility macro to ease definition of testcases toggling mode EL
+ */
+
+#define DEFINE_TESTCASE_MANGLE_PSTATE_INVALID_MODE(_mode) \
+ \
+static int mangle_invalid_pstate_run(struct tdescr *td, siginfo_t *si, \
+ ucontext_t *uc) \
+{ \
+ ASSERT_GOOD_CONTEXT(uc); \
+ \
+ uc->uc_mcontext.pstate &= ~PSR_MODE_MASK; \
+ uc->uc_mcontext.pstate |= PSR_MODE_EL ## _mode; \
+ \
+ return 1; \
+} \
+ \
+struct tdescr tde = { \
+ .sanity_disabled = true, \
+ .name = "MANGLE_PSTATE_INVALID_MODE_EL"#_mode, \
+ .descr = "Mangling uc_mcontext INVALID MODE EL"#_mode, \
+ .sig_trig = SIGUSR1, \
+ .sig_ok = SIGSEGV, \
+ .run = mangle_invalid_pstate_run, \
+}
diff --git a/tools/testing/selftests/arm64/signal/testcases/testcases.c b/tools/testing/selftests/arm64/signal/testcases/testcases.c
new file mode 100644
index 000000000..a3ac5c2d8
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/testcases.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2019 ARM Limited */
+#include "testcases.h"
+
+struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
+ size_t resv_sz, size_t *offset)
+{
+ size_t offs = 0;
+ struct _aarch64_ctx *found = NULL;
+
+ if (!head || resv_sz < HDR_SZ)
+ return found;
+
+ while (offs <= resv_sz - HDR_SZ &&
+ head->magic != magic && head->magic) {
+ offs += head->size;
+ head = GET_RESV_NEXT_HEAD(head);
+ }
+ if (head->magic == magic) {
+ found = head;
+ if (offset)
+ *offset = offs;
+ }
+
+ return found;
+}
+
+bool validate_extra_context(struct extra_context *extra, char **err)
+{
+ struct _aarch64_ctx *term;
+
+ if (!extra || !err)
+ return false;
+
+ fprintf(stderr, "Validating EXTRA...\n");
+ term = GET_RESV_NEXT_HEAD(&extra->head);
+ if (!term || term->magic || term->size) {
+ *err = "Missing terminator after EXTRA context";
+ return false;
+ }
+ if (extra->datap & 0x0fUL)
+ *err = "Extra DATAP misaligned";
+ else if (extra->size & 0x0fUL)
+ *err = "Extra SIZE misaligned";
+ else if (extra->datap != (uint64_t)term + sizeof(*term))
+ *err = "Extra DATAP misplaced (not contiguous)";
+ if (*err)
+ return false;
+
+ return true;
+}
+
+bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err)
+{
+ bool terminated = false;
+ size_t offs = 0;
+ int flags = 0;
+ struct extra_context *extra = NULL;
+ struct _aarch64_ctx *head =
+ (struct _aarch64_ctx *)uc->uc_mcontext.__reserved;
+
+ if (!err)
+ return false;
+ /* Walk till the end terminator verifying __reserved contents */
+ while (head && !terminated && offs < resv_sz) {
+ if ((uint64_t)head & 0x0fUL) {
+ *err = "Misaligned HEAD";
+ return false;
+ }
+
+ switch (head->magic) {
+ case 0:
+ if (head->size)
+ *err = "Bad size for terminator";
+ else
+ terminated = true;
+ break;
+ case FPSIMD_MAGIC:
+ if (flags & FPSIMD_CTX)
+ *err = "Multiple FPSIMD_MAGIC";
+ else if (head->size !=
+ sizeof(struct fpsimd_context))
+ *err = "Bad size for fpsimd_context";
+ flags |= FPSIMD_CTX;
+ break;
+ case ESR_MAGIC:
+ if (head->size != sizeof(struct esr_context))
+ *err = "Bad size for esr_context";
+ break;
+ case SVE_MAGIC:
+ if (flags & SVE_CTX)
+ *err = "Multiple SVE_MAGIC";
+ else if (head->size !=
+ sizeof(struct sve_context))
+ *err = "Bad size for sve_context";
+ flags |= SVE_CTX;
+ break;
+ case EXTRA_MAGIC:
+ if (flags & EXTRA_CTX)
+ *err = "Multiple EXTRA_MAGIC";
+ else if (head->size !=
+ sizeof(struct extra_context))
+ *err = "Bad size for extra_context";
+ flags |= EXTRA_CTX;
+ extra = (struct extra_context *)head;
+ break;
+ case KSFT_BAD_MAGIC:
+ /*
+ * This is a BAD magic header defined
+ * artificially by a testcase and surely
+ * unknown to the Kernel parse_user_sigframe().
+ * It MUST cause a Kernel induced SEGV
+ */
+ *err = "BAD MAGIC !";
+ break;
+ default:
+ /*
+ * A still unknown Magic: potentially freshly added
+ * to the Kernel code and still unknown to the
+ * tests.
+ */
+ fprintf(stdout,
+ "SKIP Unknown MAGIC: 0x%X - Is KSFT arm64/signal up to date ?\n",
+ head->magic);
+ break;
+ }
+
+ if (*err)
+ return false;
+
+ offs += head->size;
+ if (resv_sz < offs + sizeof(*head)) {
+ *err = "HEAD Overrun";
+ return false;
+ }
+
+ if (flags & EXTRA_CTX)
+ if (!validate_extra_context(extra, err))
+ return false;
+
+ head = GET_RESV_NEXT_HEAD(head);
+ }
+
+ if (terminated && !(flags & FPSIMD_CTX)) {
+ *err = "Missing FPSIMD";
+ return false;
+ }
+
+ return true;
+}
+
+/*
+ * This function walks through the records inside the provided reserved area
+ * trying to find enough space to fit @need_sz bytes: if not enough space is
+ * available and an extra_context record is present, it throws away the
+ * extra_context record.
+ *
+ * It returns a pointer to a new header where it is possible to start storing
+ * our need_sz bytes.
+ *
+ * @shead: points to the start of reserved area
+ * @need_sz: needed bytes
+ * @resv_sz: reserved area size in bytes
+ * @offset: if not null, this will be filled with the offset of the return
+ * head pointer from @shead
+ *
+ * @return: pointer to a new head where to start storing need_sz bytes, or
+ * NULL if space could not be made available.
+ */
+struct _aarch64_ctx *get_starting_head(struct _aarch64_ctx *shead,
+ size_t need_sz, size_t resv_sz,
+ size_t *offset)
+{
+ size_t offs = 0;
+ struct _aarch64_ctx *head;
+
+ head = get_terminator(shead, resv_sz, &offs);
+ /* not found a terminator...no need to update offset if any */
+ if (!head)
+ return head;
+ if (resv_sz - offs < need_sz) {
+ fprintf(stderr, "Low on space:%zd. Discarding extra_context.\n",
+ resv_sz - offs);
+ head = get_header(shead, EXTRA_MAGIC, resv_sz, &offs);
+ if (!head || resv_sz - offs < need_sz) {
+ fprintf(stderr,
+ "Failed to reclaim space on sigframe.\n");
+ return NULL;
+ }
+ }
+
+ fprintf(stderr, "Available space:%zd\n", resv_sz - offs);
+ if (offset)
+ *offset = offs;
+ return head;
+}
diff --git a/tools/testing/selftests/arm64/signal/testcases/testcases.h b/tools/testing/selftests/arm64/signal/testcases/testcases.h
new file mode 100644
index 000000000..ad884c135
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/testcases.h
@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 ARM Limited */
+#ifndef __TESTCASES_H__
+#define __TESTCASES_H__
+
+#include <stddef.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <signal.h>
+
+/* Architecture specific sigframe definitions */
+#include <asm/sigcontext.h>
+
+#define FPSIMD_CTX (1 << 0)
+#define SVE_CTX (1 << 1)
+#define EXTRA_CTX (1 << 2)
+
+#define KSFT_BAD_MAGIC 0xdeadbeef
+
+#define HDR_SZ \
+ sizeof(struct _aarch64_ctx)
+
+#define GET_SF_RESV_HEAD(sf) \
+ (struct _aarch64_ctx *)(&(sf).uc.uc_mcontext.__reserved)
+
+#define GET_SF_RESV_SIZE(sf) \
+ sizeof((sf).uc.uc_mcontext.__reserved)
+
+#define GET_UCP_RESV_SIZE(ucp) \
+ sizeof((ucp)->uc_mcontext.__reserved)
+
+#define ASSERT_BAD_CONTEXT(uc) do { \
+ char *err = NULL; \
+ if (!validate_reserved((uc), GET_UCP_RESV_SIZE((uc)), &err)) { \
+ if (err) \
+ fprintf(stderr, \
+ "Using badly built context - ERR: %s\n",\
+ err); \
+ } else { \
+ abort(); \
+ } \
+} while (0)
+
+#define ASSERT_GOOD_CONTEXT(uc) do { \
+ char *err = NULL; \
+ if (!validate_reserved((uc), GET_UCP_RESV_SIZE((uc)), &err)) { \
+ if (err) \
+ fprintf(stderr, \
+ "Detected BAD context - ERR: %s\n", err);\
+ abort(); \
+ } else { \
+ fprintf(stderr, "uc context validated.\n"); \
+ } \
+} while (0)
+
+/*
+ * A simple record-walker for __reserved area: it walks through assuming
+ * only to find a proper struct __aarch64_ctx header descriptor.
+ *
+ * Instead it makes no assumptions on the content and ordering of the
+ * records, any needed bounds checking must be enforced by the caller
+ * if wanted: this way can be used by caller on any maliciously built bad
+ * contexts.
+ *
+ * head->size accounts both for payload and header _aarch64_ctx size !
+ */
+#define GET_RESV_NEXT_HEAD(h) \
+ (struct _aarch64_ctx *)((char *)(h) + (h)->size)
+
+struct fake_sigframe {
+ siginfo_t info;
+ ucontext_t uc;
+};
+
+
+bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err);
+
+bool validate_extra_context(struct extra_context *extra, char **err);
+
+struct _aarch64_ctx *get_header(struct _aarch64_ctx *head, uint32_t magic,
+ size_t resv_sz, size_t *offset);
+
+static inline struct _aarch64_ctx *get_terminator(struct _aarch64_ctx *head,
+ size_t resv_sz,
+ size_t *offset)
+{
+ return get_header(head, 0, resv_sz, offset);
+}
+
+static inline void write_terminator_record(struct _aarch64_ctx *tail)
+{
+ if (tail) {
+ tail->magic = 0;
+ tail->size = 0;
+ }
+}
+
+struct _aarch64_ctx *get_starting_head(struct _aarch64_ctx *shead,
+ size_t need_sz, size_t resv_sz,
+ size_t *offset);
+#endif