Added a simple fake_sigreturn testcase which places a valid
sigframe on a non-16 bytes aligned SP.
fake_sigretrun() helper function has been patched accordingly
to support placing a sigframe on a non-16 bytes aligned address.
Expects a SIGSEGV on test PASS.
Adds also a test TODO lists holding some further test ideas.
Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
Re-added this text after fixing the forced misaglinment procedure in
fake_sigreturn() itself: require a ZERO alignment and you'll get
your sigframe placed on a misaligned SP (2-bytes off the 16-align)
---
.../testing/selftests/arm64/signal/signals.S | 21 +++++++++----
.../arm64/signal/testcases/TODO.readme | 8 +++++
.../testcases/fake_sigreturn_misaligned_sp.c | 30 +++++++++++++++++++
3 files changed, 53 insertions(+), 6 deletions(-)
create mode 100644 tools/testing/selftests/arm64/signal/testcases/TODO.readme
create mode 100644 tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c
diff --git a/tools/testing/selftests/arm64/signal/signals.S b/tools/testing/selftests/arm64/signal/signals.S
index 6262b877400b..2099871176ed 100644
--- a/tools/testing/selftests/arm64/signal/signals.S
+++ b/tools/testing/selftests/arm64/signal/signals.S
@@ -13,19 +13,28 @@ call_fmt:
.globl fake_sigreturn
-/* fake_sigreturn x0:&sigframe, x1:sigframe_size, x2:alignment_SP */
+/* fake_sigreturn x0:&sigframe, x1:sigframe_sz, x2:align */
fake_sigreturn:
- mov x20, x0
- mov x21, x1
- mov x22, x2
- mov x23, sp
- /* create space on the stack for fake sigframe..."x22"-aligned */
+ /* Save args and decide which aligment to enforce */
+ mov x23, sp
+ mov x20, x0
+ mov x21, x1
+ /* x22 and x24 used for forcing alignment or misalignment */
+ mov x22, x2
+ mov x24, #0
+ cbnz x22, 1f
+ mov x22, #16
+ mov x24, #2
+
+1: /* create space on the stack for fake sigframe..."x22"-aligned */
mov x0, #0
add x0, x21, x22
sub x22, x22, #1
bic x0, x0, x22
sub x23, x23, x0
+ /* force misaligned by x24 bytes if required alignment was zero */
+ add x23, x23, x24
ldr x0, =call_fmt
mov x1, x21
diff --git a/tools/testing/selftests/arm64/signal/testcases/TODO.readme b/tools/testing/selftests/arm64/signal/testcases/TODO.readme
new file mode 100644
index 000000000000..5c949492e7ab
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/TODO.readme
@@ -0,0 +1,8 @@
+Some more possible ideas for signals tests:
+
+- fake_sigreturn_unmapped_sp
+- fake_sigreturn_kernelspace_sp
+- fake_sigreturn_sve_bad_extra_context
+- mangle_sve_invalid_extra_context
+- mangle_pstate_invalid_el for H modes (+ macroization ?)
+- fake_sigreturn_overflow_reserved
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 000000000000..3ee8c500c7d1
--- /dev/null
+++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2019 ARM Limited */
+
+#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 (=!16) SP */
+ fake_sigreturn(&sf, sizeof(sf), 0);
+
+ return 1;
+}
+
+struct tdescr tde = {
+ .name = "FAKE_SIGRETURN_MISALIGNED_SP",
+ .descr = "Triggers a fake sigreturn with a misaligned sigframe on SP",
+ .sig_ok = SIGSEGV,
+ .timeout = 3,
+ .run = fake_sigreturn_misaligned_run,
+};
--
2.17.1
