On Thu, Feb 23, 2017 at 02:26:04PM -0800, Dave Hansen wrote:
>
>
> Shuah, I assume you'll take this patch in through the selftests tree.
>
> --
> From: Dave Hansen <dave.han...@linux.intel.com>
>
> The kernel pkeys code had a minor bug where it did some large shifts
> to an integer which is undefined behavior in C. It didn't cause any
> real harm, but it is screwy behavior that the kernel should have
> rejected.
>
> Add a test case for this.
>
> Signed-off-by: Dave Hansen <dave.han...@linux.intel.com>
> ec: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
> Cc: Shuah Khan <sh...@kernel.org>
> Cc: linux-kselft...@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: x...@kernel.org
> ---
>
> b/tools/testing/selftests/x86/protection_keys.c | 25
> ++++++++++++++++++++++++
> 1 file changed, 25 insertions(+)
>
> diff -puN
> tools/testing/selftests/x86/protection_keys.c~pkeys-better-selftests-of-random-pkey
> tools/testing/selftests/x86/protection_keys.c
> ---
> a/tools/testing/selftests/x86/protection_keys.c~pkeys-better-selftests-of-random-pkey
> 2017-02-23 14:21:05.168391529 -0800
> +++ b/tools/testing/selftests/x86/protection_keys.c 2017-02-23
> 14:23:03.244671815 -0800
> @@ -1123,6 +1123,30 @@ void test_pkey_syscalls_on_non_allocated
> }
>
> /* Assumes that all pkeys other than 'pkey' are unallocated */
> +void test_pkey_syscalls_on_non_allocated_random_pkey(int *ptr, u16 pkey)
> +{
> + int err;
> + int nr_tests = 0;
> +
> + while (nr_tests < 1000) {
> + int test_pkey = rand();
rand(3) doesn't generate negative numbers. Would be good to cover this
case too.
int test_pkey = rand() - RAND_MAX/2;
?
Otherwise looks good to me.
--
Kirill A. Shutemov
