[PATCH v18 17/24] selftests/vm/pkeys: Associate key on a mapped page and detect access violation
From: Sandipan Das <hidden>
Date: 2020-01-30 06:38:13
Also in:
linux-arch, linux-kselftest, linux-mm
Subsystem:
kernel selftest framework, the rest · Maintainers:
Shuah Khan, Linus Torvalds
From: Ram Pai <redacted> Detect access-violation on a page to which access-disabled key is associated much after the page is mapped. cc: Dave Hansen <redacted> cc: Florian Weimer <redacted> Signed-off-by: Ram Pai <redacted> Acked-by: Dave Hansen <redacted> Signed-off: Sandipan Das [off-list ref] --- tools/testing/selftests/vm/protection_keys.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 95f173049f43..f65d384ef6a0 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c@@ -984,6 +984,24 @@ void test_read_of_access_disabled_region(int *ptr, u16 pkey) dprintf1("*ptr: %d\n", ptr_contents); expected_pkey_fault(pkey); } + +void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr, + u16 pkey) +{ + int ptr_contents; + + dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", + pkey, ptr); + ptr_contents = read_ptr(ptr); + dprintf1("reading ptr before disabling the read : %d\n", + ptr_contents); + read_pkey_reg(); + pkey_access_deny(pkey); + ptr_contents = read_ptr(ptr); + dprintf1("*ptr: %d\n", ptr_contents); + expected_pkey_fault(pkey); +} + void test_write_of_write_disabled_region(int *ptr, u16 pkey) { dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
@@ -1390,6 +1408,7 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey) void (*pkey_tests[])(int *ptr, u16 pkey) = { test_read_of_write_disabled_region, test_read_of_access_disabled_region, + test_read_of_access_disabled_region_with_page_already_mapped, test_write_of_write_disabled_region, test_write_of_access_disabled_region, test_kernel_write_of_access_disabled_region,
--
2.17.1