Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/objtool/special.c b/tools/objtool/special.c
index 84f001d..fdbaa61 100644
--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -1,18 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
/*
@@ -23,6 +11,7 @@
#include <stdlib.h>
#include <string.h>
+#include "builtin.h"
#include "special.h"
#include "warn.h"
@@ -30,9 +19,9 @@
#define EX_ORIG_OFFSET 0
#define EX_NEW_OFFSET 4
-#define JUMP_ENTRY_SIZE 24
+#define JUMP_ENTRY_SIZE 16
#define JUMP_ORIG_OFFSET 0
-#define JUMP_NEW_OFFSET 8
+#define JUMP_NEW_OFFSET 4
#define ALT_ENTRY_SIZE 13
#define ALT_ORIG_OFFSET 0
@@ -42,6 +31,7 @@
#define ALT_NEW_LEN_OFFSET 11
#define X86_FEATURE_POPCNT (4*32+23)
+#define X86_FEATURE_SMAP (9*32+20)
struct special_entry {
const char *sec;
@@ -110,6 +100,22 @@
*/
if (feature == X86_FEATURE_POPCNT)
alt->skip_orig = true;
+
+ /*
+ * If UACCESS validation is enabled; force that alternative;
+ * otherwise force it the other way.
+ *
+ * What we want to avoid is having both the original and the
+ * alternative code flow at the same time, in that case we can
+ * find paths that see the STAC but take the NOP instead of
+ * CLAC and the other way around.
+ */
+ if (feature == X86_FEATURE_SMAP) {
+ if (uaccess)
+ alt->skip_orig = true;
+ else
+ alt->skip_alt = true;
+ }
}
orig_rela = find_rela_by_dest(sec, offset + entry->orig);