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| author | Dave Hansen <dave.hansen@linux.intel.com> | 2018-05-09 20:13:56 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-05-14 12:14:45 +0300 |
| commit | 3488a600d90bcaf061b104dbcfbdc8d99b398312 (patch) | |
| tree | c56c21499e9a180a2ffde5a37bcb9179a78c6d5e /tools | |
| parent | acb25d761d6f2f64e785ccefc71e54f244f1eda4 (diff) | |
| download | linux-3488a600d90bcaf061b104dbcfbdc8d99b398312.tar.xz | |
x86/pkeys/selftests: Add a test for pkey 0
Protection key 0 is the default key for all memory and will
not normally come back from pkey_alloc(). But, you might
still want pass it to mprotect_pkey().
This check ensures that you can use pkey 0.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellermen <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171356.9E40B254@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/x86/protection_keys.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/tools/testing/selftests/x86/protection_keys.c b/tools/testing/selftests/x86/protection_keys.c index 986ed38a2b25..460b4bdf4c1e 100644 --- a/tools/testing/selftests/x86/protection_keys.c +++ b/tools/testing/selftests/x86/protection_keys.c @@ -1184,6 +1184,35 @@ void test_pkey_alloc_exhaust(int *ptr, u16 pkey) } } +/* + * pkey 0 is special. It is allocated by default, so you do not + * have to call pkey_alloc() to use it first. Make sure that it + * is usable. + */ +void test_mprotect_with_pkey_0(int *ptr, u16 pkey) +{ + long size; + int prot; + + assert(pkey_last_malloc_record); + size = pkey_last_malloc_record->size; + /* + * This is a bit of a hack. But mprotect() requires + * huge-page-aligned sizes when operating on hugetlbfs. + * So, make sure that we use something that's a multiple + * of a huge page when we can. + */ + if (size >= HPAGE_SIZE) + size = HPAGE_SIZE; + prot = pkey_last_malloc_record->prot; + + /* Use pkey 0 */ + mprotect_pkey(ptr, size, prot, 0); + + /* Make sure that we can set it back to the original pkey. */ + mprotect_pkey(ptr, size, prot, pkey); +} + void test_ptrace_of_child(int *ptr, u16 pkey) { __attribute__((__unused__)) int peek_result; @@ -1378,6 +1407,7 @@ void (*pkey_tests[])(int *ptr, u16 pkey) = { test_kernel_gup_write_to_write_disabled_region, test_executing_on_unreadable_memory, test_implicit_mprotect_exec_only_memory, + test_mprotect_with_pkey_0, test_ptrace_of_child, test_pkey_syscalls_on_non_allocated_pkey, test_pkey_syscalls_bad_args, |