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[v16,17/23] selftests/vm/pkeys: Associate key on a mapped page and detect access violation

Message ID fda50263252327f9280f1a42e648630c1c47e48a.1579265066.git.sandipan@linux.ibm.com
State New
Headers show
Series [v16,01/23] selftests/x86/pkeys: Move selftests to arch-neutral directory | expand

Commit Message

Sandipan Das Jan. 17, 2020, 12:49 p.m. UTC 
From: Ram Pai <linuxram@us.ibm.com>

Detect access-violation on a page to which access-disabled
key is associated much after the page is mapped.

cc: Dave Hansen <dave.hansen@intel.com>
cc: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off: Sandipan Das <sandipan@linux.ibm.com>
---
 tools/testing/selftests/vm/protection_keys.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
diff mbox series

Patch

diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 4a0677e618ac..526ad2fea316 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -983,6 +983,24 @@  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);
@@ -1389,6 +1407,7 @@  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,