From 5407092d7501f0949452083a76a1103e228c1ea3 Mon Sep 17 00:00:00 2001
From: Ram Pai <linuxram@us.ibm.com>
Date: Mon, 22 Jan 2018 10:52:13 -0800
Subject: [PATCH 26/30] selftests/vm: testcases must restore pkey-permissions

References: FATE#322447, bsc#1078248
Patch-mainline: submitted https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-January/168234.html

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 <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 tools/testing/selftests/vm/protection_keys.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 3e9e36d48706..578358733646 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 */
-- 
2.13.6