On 13/08/2019 17:26, Dave Martin wrote:
> On Fri, Aug 02, 2019 at 06:02:58PM +0100, Cristian Marussi wrote:
>> Added a simple fake_sigreturn testcase which builds a ucontext_t
>
> Add
Ok
>
>> with an anomalous additional fpsimd_context and place it onto the stack.
>> Expects a SIGSEGV on test PASS.
>>
>> Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
>> ---
>> .../arm64/signal/testcases/.gitignore | 1 +
>> .../fake_sigreturn_duplicated_fpsimd.c | 62 +++++++++++++++++++
>> 2 files changed, 63 insertions(+)
>> create mode 100644 tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_duplicated_fpsimd.c
>>
>> diff --git a/tools/testing/selftests/arm64/signal/testcases/.gitignore b/tools/testing/selftests/arm64/signal/testcases/.gitignore
>> index 17d1c5e73319..94f9baaf638c 100644
>> --- a/tools/testing/selftests/arm64/signal/testcases/.gitignore
>> +++ b/tools/testing/selftests/arm64/signal/testcases/.gitignore
>> @@ -7,3 +7,4 @@ mangle_pstate_ssbs_regs
>> fake_sigreturn_bad_magic
>> fake_sigreturn_bad_size_for_magic0
>> fake_sigreturn_missing_fpsimd
>> +fake_sigreturn_duplicated_fpsimd
>> 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 000000000000..09af7a0f8776
>> --- /dev/null
>> +++ b/tools/testing/selftests/arm64/signal/testcases/fake_sigreturn_duplicated_fpsimd.c
>> @@ -0,0 +1,62 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/* Copyright (C) 2019 ARM Limited */
>> +
>
> signal.h?
Ok
>
>> +#include <stdio.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)
>> +{
>> + size_t resv_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);
>> + /*
>> + * find the terminator, preserving existing headers
>> + * and verify amount of spare room in __reserved area.
>> + */
>> + head = get_terminator(shead, resv_sz, &offset);
>> + /*
>> + * try stripping extra_context header when low on space:
>> + * we need at least space for one additional fpsimd_context
>> + */
>> + if (head && resv_sz - offset < sizeof(struct fpsimd_context)) {
>> + fprintf(stderr, "Low on space:%zd. Discarding extra_context.\n",
>> + resv_sz - offset);
>> + head = get_header(shead, EXTRA_MAGIC, resv_sz, &offset);
>> + }
>> +
>> + /* just give up and timeout if still not enough space */
>> + if (head &&
>> + resv_sz - offset >= sizeof(struct fpsimd_context) + HDR_SZ) {
>> + fprintf(stderr, "Mangling template header. Spare space:%zd\n",
>> + resv_sz - offset);
>> + /* Add a spurios 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), 16);
>> + }
>> +
>> + return 1;
>> +}
>
I'll convert to use new helper get_starting_head() to make space in __reserved.
Cheers
Cristian
> [...]
>
> Otherwise looks ok.
>
> Cheers
> ---Dave
>
