diff mbox series

[v5,11/11] kselftest: arm64: fake_sigreturn_misaligned_sp

Message ID 20190902112932.36129-12-cristian.marussi@arm.com (mailing list archive)
State New
Headers show
Series Add arm64/signal initial kselftest support | expand

Commit Message

Cristian Marussi Sept. 2, 2019, 11:29 a.m. UTC 
Add a simple fake_sigreturn testcase which places a valid sigframe on a
non-16 bytes aligned SP. Expects a SIGSEGV on test PASS.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v3 --> v4
- fix commit
- use new fake_sigreturn misalig_bytes params
- removed TODO
- added test description
---
 .../testcases/fake_sigreturn_misaligned_sp.c  | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c

Comments

Dave Martin Sept. 4, 2019, 11:49 a.m. UTC | #1 
On Mon, Sep 02, 2019 at 12:29:32pm +0100, Cristian Marussi wrote:
> Add a simple fake_sigreturn testcase which places a valid sigframe on a
> non-16 bytes aligned SP. Expects a SIGSEGV on test PASS.
> 
> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
> ---
> v3 --> v4
> - fix commit
> - use new fake_sigreturn misalig_bytes params
> - removed TODO
> - added test description
> ---
>  .../testcases/fake_sigreturn_misaligned_sp.c  | 37 +++++++++++++++++++
>  1 file changed, 37 insertions(+)
>  create mode 100644 tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c
> 
> 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..1e089e66f9f3
> --- /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);

Can we add tests on the TODO list for other misalignments?

 a) 4 (i.e., __alignof__(struct _aarch64_ctx))
 b) 8 (i.e., sizeof(struct _aarch64_ctx))

This may help catch potential wrong-bitmask bugs in the kernel when
checking the alignment.  Similarly to my suggestion on patch 10, these
can go on the TODO list and added later (probably macro-ised).

For now, let's get this series settled as-is -- so, after responding to
nits:

Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Cristian Marussi Sept. 9, 2019, 6:32 p.m. UTC | #2 
On 04/09/2019 12:49, Dave Martin wrote:
> On Mon, Sep 02, 2019 at 12:29:32pm +0100, Cristian Marussi wrote:
>> Add a simple fake_sigreturn testcase which places a valid sigframe on a
>> non-16 bytes aligned SP. Expects a SIGSEGV on test PASS.
>>
>> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
>> ---
>> v3 --> v4
>> - fix commit
>> - use new fake_sigreturn misalig_bytes params
>> - removed TODO
>> - added test description
>> ---
>>  .../testcases/fake_sigreturn_misaligned_sp.c  | 37 +++++++++++++++++++
>>  1 file changed, 37 insertions(+)
>>  create mode 100644 tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_misaligned_sp.c
>>
>> 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..1e089e66f9f3
>> --- /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);
> 
> Can we add tests on the TODO list for other misalignments?
> 
>  a) 4 (i.e., __alignof__(struct _aarch64_ctx))
>  b) 8 (i.e., sizeof(struct _aarch64_ctx))
> 
> This may help catch potential wrong-bitmask bugs in the kernel when
> checking the alignment.  Similarly to my suggestion on patch 10, these
> can go on the TODO list and added later (probably macro-ised).
> 
Ok
> For now, let's get this series settled as-is -- so, after responding to
> nits:
> 
> Reviewed-by: Dave Martin <Dave.Martin@arm.com>
> 

Thanks

Cristian
diff mbox series

Patch

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..1e089e66f9f3
--- /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,
+};