Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752552AbdGPEA3 (ORCPT ); Sun, 16 Jul 2017 00:00:29 -0400 Received: from mail-qt0-f194.google.com ([209.85.216.194]:36090 "EHLO mail-qt0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751552AbdGPEAW (ORCPT ); Sun, 16 Jul 2017 00:00:22 -0400 From: Ram Pai To: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, dave.hansen@intel.com, hbabu@us.ibm.com, linuxram@us.ibm.com, arnd@arndb.de, akpm@linux-foundation.org, corbet@lwn.net, mingo@redhat.com, mhocko@kernel.org Subject: [RFC v6 56/62] selftest/vm: detect no key violation on a freed key Date: Sat, 15 Jul 2017 20:56:58 -0700 Message-Id: <1500177424-13695-57-git-send-email-linuxram@us.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1500177424-13695-1-git-send-email-linuxram@us.ibm.com> References: <1500177424-13695-1-git-send-email-linuxram@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1647 Lines: 53 a access-denied key should not trigger any key violation after the key has been freed. Signed-off-by: Ram Pai --- tools/testing/selftests/vm/protection_keys.c | 25 +++++++++++++++++++++++++ 1 files changed, 25 insertions(+), 0 deletions(-) diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c index bf27bcd..47c23cc 100644 --- a/tools/testing/selftests/vm/protection_keys.c +++ b/tools/testing/selftests/vm/protection_keys.c @@ -1026,6 +1026,30 @@ void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr, expected_pkey_fault(pkey); } +void test_read_of_access_disabled_but_freed_key_region(int *ptr, u16 pkey) +{ + int ptr_contents; + + dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", + pkey, ptr); + + /* read the content */ + ptr_contents = read_ptr(ptr); + do_not_expect_pkey_fault(); + + /* deny key access */ + pkey_access_deny(pkey); + ptr_contents = read_ptr(ptr); + dprintf1("*ptr: %d\n", ptr_contents); + expected_pkey_fault(pkey); + + /* free the key without restoring access */ + pkey_access_deny(pkey); + sys_pkey_free(pkey); + ptr_contents = read_ptr(ptr); + do_not_expect_pkey_fault(); +} + void test_write_of_write_disabled_region(int *ptr, u16 pkey) { dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey); @@ -1333,6 +1357,7 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey) test_pkey_syscalls_on_non_allocated_pkey, test_pkey_syscalls_bad_args, test_pkey_alloc_exhaust, + test_read_of_access_disabled_but_freed_key_region, }; void run_tests_once(void) -- 1.7.1