Add some arm64/signal specific boilerplate and utility code to help
further testcases' development.
Introduce also one simple testcase mangle_pstate_invalid_compat_toggle
and some related helpers: it is a simple mangle testcase which messes
with the ucontext_t from within the signal handler, trying to toggle
PSTATE state bits to switch the system between 32bit/64bit execution
state. Expects SIGSEGV on test PASS.
Reviewed-by: Dave Martin <Dave.Martin@xxxxxxx>
Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
v7 --> v8
- removed unused SSBS_SYSREG
v6 --> v7
- removed ambiguos fprintf in test_init
- fixed spacing
v5 --> v6
- fix commit msg
- feat_names is char const *const
- better supported options check and reporting
- removed critical asserts to avoid issues with NDEBUG
- more robust get_header
- fix validation for ESR_CONTEXT size
- add more explicit comment in GET_RESV_NEXT_HEAD() macro
- refactored default_handler()
- feats_ok() now public
- call always test_results() no matter the outcome of test_run()
v4 --> v5
- moved kernel headers include search to top level KSFT arm64 Makefile
- removed warning about kernel headers not found
- moved testcases/.gitignore up one level
v3 --> v4
- removed standalone mode
- fixed arm64/signal/README
- add file level comments: test layout / test description
- reduced verbosity
- removed spurious headers includes
- reviewed ID_AA64MMFR[1,2]_EL1 macros
- removed unused feats_ok
- simplified CPU features gathering
- reviewed included headers
- fixed/refactored get_header() and validation routines
- added test description
---
tools/testing/selftests/arm64/Makefile | 2 +-
.../testing/selftests/arm64/signal/.gitignore | 3 +
tools/testing/selftests/arm64/signal/Makefile | 32 ++
tools/testing/selftests/arm64/signal/README | 59 ++++
.../selftests/arm64/signal/test_signals.c | 29 ++
.../selftests/arm64/signal/test_signals.h | 109 +++++++
.../arm64/signal/test_signals_utils.c | 297 ++++++++++++++++++
.../arm64/signal/test_signals_utils.h | 19 ++
.../mangle_pstate_invalid_compat_toggle.c | 31 ++
.../arm64/signal/testcases/testcases.c | 150 +++++++++
.../arm64/signal/testcases/testcases.h | 100 ++++++
11 files changed, 830 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/arm64/signal/.gitignore
create mode 100644 tools/testing/selftests/arm64/signal/Makefile
create mode 100644 tools/testing/selftests/arm64/signal/README
create mode 100644 tools/testing/selftests/arm64/signal/test_signals.c
create mode 100644 tools/testing/selftests/arm64/signal/test_signals.h
create mode 100644 tools/testing/selftests/arm64/signal/test_signals_utils.c
create mode 100644 tools/testing/selftests/arm64/signal/test_signals_utils.h
create mode 100644 tools/testing/selftests/arm64/signal/testcases/mangle_pstate_invalid_compat_toggle.c
create mode 100644 tools/testing/selftests/arm64/signal/testcases/testcases.c
create mode 100644 tools/testing/selftests/arm64/signal/testcases/testcases.h
diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile
index cd27ca689224..93b567d23c8b 100644
--- a/tools/testing/selftests/arm64/Makefile
+++ b/tools/testing/selftests/arm64/Makefile
@@ -4,7 +4,7 @@
ARCH ?= $(shell uname -m 2>/dev/null || echo not)
ifneq (,$(filter $(ARCH),aarch64 arm64))
-ARM64_SUBTARGETS ?= tags
+ARM64_SUBTARGETS ?= tags signal
else
ARM64_SUBTARGETS :=
endif
diff --git a/tools/testing/selftests/arm64/signal/.gitignore b/tools/testing/selftests/arm64/signal/.gitignore
new file mode 100644
index 000000000000..e5aeae45febb
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/.gitignore
@@ -0,0 +1,3 @@
+!*.[ch]
+mangle_*
+fake_sigreturn_*
diff --git a/tools/testing/selftests/arm64/signal/Makefile b/tools/testing/selftests/arm64/signal/Makefile
new file mode 100644
index 000000000000..f78f5190e3d4
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/Makefile
@@ -0,0 +1,32 @@
+# 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)/
+
+clean:
+ $(CLEAN)
+ rm -f $(PROGS)
+
+# Common test-unit targets to build common-layout test-cases executables
+# Needs secondary expansion to properly include the testcase c-file in pre-reqs
+.SECONDEXPANSION:
+$(PROGS): test_signals.c test_signals_utils.c testcases/testcases.c $$@.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 000000000000..967a531b245c
--- /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/test_signals.c b/tools/testing/selftests/arm64/signal/test_signals.c
new file mode 100644
index 000000000000..cb970346b280
--- /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_run(current);
+ test_result(current);
+ test_cleanup(current);
+ }
+
+ return current->pass ? KSFT_PASS : KSFT_FAIL;
+}
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 000000000000..3fd4499f00bf
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals.h
@@ -0,0 +1,109 @@
+/* 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"); \
+}
+
+/* Regs encoding and masks naming copied in from sysreg.h */
+#define SYS_ID_AA64MMFR1_EL1 S3_0_C0_C7_1 /* MRS Emulated */
+#define SYS_ID_AA64MMFR2_EL1 S3_0_C0_C7_2 /* MRS Emulated */
+#define ID_AA64MMFR1_PAN_SHIFT 20
+#define ID_AA64MMFR2_UAO_SHIFT 4
+
+/* Local Helpers */
+#define ID_AA64MMFR1_EL1_PAN_SUPPORTED(val) \
+ (!!((val) & (0xfUL << ID_AA64MMFR1_PAN_SHIFT)))
+#define ID_AA64MMFR2_EL1_UAO_SUPPORTED(val) \
+ (!!((val) & (0xfUL << ID_AA64MMFR2_UAO_SHIFT)))
+
+/*
+ * Feature flags used in tdescr.feats_required to specify
+ * any feature by the test
+ */
+enum {
+ FSSBS_BIT,
+ FPAN_BIT,
+ FUAO_BIT,
+ FMAX_END
+};
+
+#define FEAT_SSBS (1UL << FSSBS_BIT)
+#define FEAT_PAN (1UL << FPAN_BIT)
+#define FEAT_UAO (1UL << FUAO_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;
+ /* optional sa_flags for the installed handler */
+ int sa_flags;
+ ucontext_t saved_uc;
+ /* optional test private data */
+ void *priv;
+
+ /* a custom setup function to be called before test starts */
+ int (*setup)(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 test starting */
+ 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 000000000000..ff24db6f9d06
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals_utils.c
@@ -0,0 +1,297 @@
+// 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 "test_signals.h"
+#include "test_signals_utils.h"
+#include "testcases/testcases.h"
+
+extern struct tdescr *current;
+
+static char const *const feats_names[FMAX_END] = {
+ " SSBS ",
+ " PAN ",
+ " UAO ",
+};
+
+#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->pass)
+ fprintf(stderr, "==>> completed. PASS(1)\n");
+ else
+ fprintf(stdout, "==>> completed. FAIL(0)\n");
+ if (force_exit)
+ exit(td->pass ? EXIT_SUCCESS : EXIT_FAILURE);
+}
+
+/*
+ * 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 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 == 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);
+}
+
+static int test_init(struct tdescr *td)
+{
+ 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_CPUID) {
+ uint64_t val = 0;
+
+ /* Uses MRS emulation to check capability */
+ get_regval(SYS_ID_AA64MMFR1_EL1, val);
+ if (ID_AA64MMFR1_EL1_PAN_SUPPORTED(val))
+ td->feats_supported |= FEAT_PAN;
+ /* Uses MRS emulation to check capability */
+ get_regval(SYS_ID_AA64MMFR2_EL1, val);
+ if (ID_AA64MMFR2_EL1_UAO_SUPPORTED(val))
+ td->feats_supported |= FEAT_UAO;
+ }
+ 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->initialized = 1;
+ 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);
+
+ if (!test_init(td))
+ return 0;
+
+ 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->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 000000000000..47a7592b7c53
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/test_signals_utils.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 ARM Limited */
+
+#ifndef __TEST_SIGNALS_UTILS_H__
+#define __TEST_SIGNALS_UTILS_H__
+
+#include "test_signals.h"
+
+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;
+}
+
+#endif
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 000000000000..2cb118b0ba05
--- /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/testcases.c b/tools/testing/selftests/arm64/signal/testcases/testcases.c
new file mode 100644
index 000000000000..1914a01222a1
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/testcases.c
@@ -0,0 +1,150 @@
+// 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);
+ 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 contiguos)";
+ 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;
+}
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 000000000000..04987f7870bc
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/testcases.h
@@ -0,0 +1,100 @@
+/* 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;
+ }
+}
+#endif
--
2.17.1
