From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x241.google.com (mail-qt0-x241.google.com [IPv6:2607:f8b0:400d:c0d::241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zQLDt3VRBzF0SM for ; Tue, 23 Jan 2018 05:53:50 +1100 (AEDT) Received: by mail-qt0-x241.google.com with SMTP id f4so23479656qtj.6 for ; Mon, 22 Jan 2018 10:53:50 -0800 (PST) Sender: Ram Pai From: Ram Pai To: shuahkh@osg.samsung.com, linux-kselftest@vger.kernel.org Cc: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@redhat.com, akpm@linux-foundation.org, dave.hansen@intel.com, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com, linuxram@us.ibm.com, arnd@arndb.de Subject: [PATCH v10 20/24] selftests/vm: testcases must restore pkey-permissions Date: Mon, 22 Jan 2018 10:52:13 -0800 Message-Id: <1516647137-11174-21-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1516647137-11174-1-git-send-email-linuxram@us.ibm.com> References: <1516647137-11174-1-git-send-email-linuxram@us.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Generally the signal handler restores the state of the pkey register before returning. However there are times when the read/write operation can legitamely fail without invoking the signal handler. Eg: A sys_read() operaton to a write-protected page should be disallowed. In such a case the state of the pkey register is not restored to its original state. The test case is responsible for restoring the key register state to its original value. Signed-off-by: Ram Pai --- tools/testing/selftests/vm/protection_keys.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c index 3e9e36d..5783587 100644 --- a/tools/testing/selftests/vm/protection_keys.c +++ b/tools/testing/selftests/vm/protection_keys.c @@ -1003,6 +1003,7 @@ void test_read_of_write_disabled_region(int *ptr, u16 pkey) ptr_contents = read_ptr(ptr); dprintf1("*ptr: %d\n", ptr_contents); dprintf1("\n"); + pkey_write_allow(pkey); } void test_read_of_access_disabled_region(int *ptr, u16 pkey) { @@ -1082,6 +1083,7 @@ void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey) ret = read(test_fd, ptr, 1); dprintf1("read ret: %d\n", ret); pkey_assert(ret); + pkey_access_allow(pkey); } void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey) { @@ -1094,6 +1096,7 @@ void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey) if (ret < 0 && (DEBUG_LEVEL > 0)) perror("verbose read result (OK for this to be bad)"); pkey_assert(ret); + pkey_write_allow(pkey); } void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey) @@ -1113,6 +1116,7 @@ void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey) vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT); dprintf1("vmsplice() ret: %d\n", vmsplice_ret); pkey_assert(vmsplice_ret == -1); + pkey_access_allow(pkey); close(pipe_fds[0]); close(pipe_fds[1]); @@ -1133,6 +1137,7 @@ void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey) if (DEBUG_LEVEL > 0) perror("futex"); dprintf1("futex() ret: %d\n", futex_ret); + pkey_write_allow(pkey); } /* Assumes that all pkeys other than 'pkey' are unallocated */ -- 1.7.1