From 742f50979db5360da396af45d1b1c9a88b44bb73 Mon Sep 17 00:00:00 2001
From: Packit <packit>
Date: Oct 27 2020 19:06:19 +0000
Subject: Apply patch rh1566890-CVE_2018_3639-speculative_store_bypass_toggle.patch


patch_name: rh1566890-CVE_2018_3639-speculative_store_bypass_toggle.patch
present_in_specfile: true
no_prefix: true

---

diff --git a/openjdk/hotspot/src/os/linux/vm/os_linux.cpp b/openjdk/hotspot/src/os/linux/vm/os_linux.cpp
index 8091f72..e5c5021 100644
--- a/openjdk/hotspot/src/os/linux/vm/os_linux.cpp
+++ b/openjdk/hotspot/src/os/linux/vm/os_linux.cpp
@@ -5041,26 +5041,43 @@ const char* os::exception_name(int exception_code, char* buf, size_t size) {
 
 /* Per task speculation control */
 #ifndef PR_GET_SPECULATION_CTRL
-#define PR_GET_SPECULATION_CTRL    52
+# define PR_GET_SPECULATION_CTRL    52
 #endif
 #ifndef PR_SET_SPECULATION_CTRL
-#define PR_SET_SPECULATION_CTRL    53
+# define PR_SET_SPECULATION_CTRL    53
 #endif
 /* Speculation control variants */
-# undef PR_SPEC_STORE_BYPASS
+#ifndef PR_SPEC_STORE_BYPASS
 # define PR_SPEC_STORE_BYPASS          0
+#endif
 /* Return and control values for PR_SET/GET_SPECULATION_CTRL */
-# undef PR_SPEC_NOT_AFFECTED
-# undef PR_SPEC_PRCTL
-# undef PR_SPEC_ENABLE
-# undef PR_SPEC_DISABLE
+
+#ifndef PR_SPEC_NOT_AFFECTED
 # define PR_SPEC_NOT_AFFECTED          0
+#endif
+#ifndef PR_SPEC_PRCTL
 # define PR_SPEC_PRCTL                 (1UL << 0)
+#endif
+#ifndef PR_SPEC_ENABLE
 # define PR_SPEC_ENABLE                (1UL << 1)
+#endif
+#ifndef PR_SPEC_DISABLE
 # define PR_SPEC_DISABLE               (1UL << 2)
+#endif
+#ifndef PR_SPEC_FORCE_DISABLE
+# define PR_SPEC_FORCE_DISABLE         (1UL << 3)
+#endif
+#ifndef PR_SPEC_DISABLE_NOEXEC
+# define PR_SPEC_DISABLE_NOEXEC        (1UL << 4)
+#endif
 
 static void set_speculation() __attribute__((constructor));
 static void set_speculation() {
+  if ( prctl(PR_SET_SPECULATION_CTRL,
+             PR_SPEC_STORE_BYPASS,
+             PR_SPEC_DISABLE_NOEXEC, 0, 0) == 0 ) {
+    return;
+  }
   prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, PR_SPEC_DISABLE, 0, 0);
 }