commit 2d79c6c09654aa40364a348bf0f9d3b6d6d51531
author Jiyong Park <jiyong@google.com> Tue Jul 19 04:40:39 2022 +0000
committer Gerrit Code Review <noreply-gerritcodereview@google.com> Tue Jul 19 04:40:39 2022 +0000
tree 9f05beee4ce492924d67bfbccb14ebd01f0c6960
parent 11e757c9ccdc93ba3ab2679effe5f7f45779fef1
parent 11d7bc52df55e487b78dce0fd70a88e5096987d9

Merge "init: don't touch mmap_rnd_compat_bits on 64-bit only builds"

init/security.cpp

diff --git a/init/security.cpp b/init/security.cpp
index 970696e..8bf4d52 100644
--- a/init/security.cpp
+++ b/init/security.cpp
@@ -15,6 +15,7 @@
  */
 
 #include "security.h"
+#include "util.h"
 
 #include <errno.h>
 #include <fcntl.h>
@@ -106,12 +107,12 @@
     return {};
 #elif defined(__aarch64__)
     // arm64 supports 18 - 33 bits depending on pagesize and VA_SIZE
-    if (SetMmapRndBitsMin(33, 24, false) && SetMmapRndBitsMin(16, 16, true)) {
+    if (SetMmapRndBitsMin(33, 24, false) && (!Has32BitAbi() || SetMmapRndBitsMin(16, 16, true))) {
         return {};
     }
 #elif defined(__x86_64__)
     // x86_64 supports 28 - 32 bits
-    if (SetMmapRndBitsMin(32, 32, false) && SetMmapRndBitsMin(16, 16, true)) {
+    if (SetMmapRndBitsMin(32, 32, false) && (!Has32BitAbi() || SetMmapRndBitsMin(16, 16, true))) {
         return {};
     }
 #elif defined(__arm__) || defined(__i386__)

init/util.cpp

diff --git a/init/util.cpp b/init/util.cpp
index 1801d17..523cce4 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -733,5 +733,10 @@
     return is_microdroid;
 }
 
+bool Has32BitAbi() {
+    static bool has = !android::base::GetProperty("ro.product.cpu.abilist32", "").empty();
+    return has;
+}
+
 }  // namespace init
 }  // namespace android

init/util.h

diff --git a/init/util.h b/init/util.h
index 47d4ff5..099b9ee 100644
--- a/init/util.h
+++ b/init/util.h
@@ -106,5 +106,6 @@
 void SetDefaultMountNamespaceReady();
 
 bool IsMicrodroid();
+bool Has32BitAbi();
 }  // namespace init
 }  // namespace android