From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f197.google.com (mail-qt0-f197.google.com [209.85.216.197]) by kanga.kvack.org (Postfix) with ESMTP id 7001C6B0273 for ; Wed, 21 Feb 2018 20:57:26 -0500 (EST) Received: by mail-qt0-f197.google.com with SMTP id y40so2823489qty.15 for ; Wed, 21 Feb 2018 17:57:26 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id f126sor1026492qkd.72.2018.02.21.17.57.25 for (Google Transport Security); Wed, 21 Feb 2018 17:57:25 -0800 (PST) From: Ram Pai Subject: [PATCH v12 20/22] selftests/vm: testcases must restore pkey-permissions Date: Wed, 21 Feb 2018 17:55:39 -0800 Message-Id: <1519264541-7621-21-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1519264541-7621-1-git-send-email-linuxram@us.ibm.com> References: <1519264541-7621-1-git-send-email-linuxram@us.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: 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 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. cc: Dave Hansen cc: Florian Weimer 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 437ee74..42c068a 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org