commit 8702dcb9927a8b60d1bc229f18bd87fc38207160
author Tom Cherry <tomcherry@google.com> Fri Oct 13 16:20:19 2017 -0700
committer Tom Cherry <tomcherry@google.com> Mon Oct 16 22:35:33 2017 +0000
tree 94cb97428714780cdd4522eada78ebbb5e6919af
parent 06254de12a9a12c5d0a7732d2a40cc3a10754b57

Only allow UTF8 encoded property values

Java already restricts properties to only UTF8 valid strings, and
this change makes this restriction also apply to all native code.

Bug: 63177684
Test: new unit tests
Change-Id: I9fa0ecc0da066b0a026db3497c0f0cbf3f5c2d5a

init/property_service.cpp

diff --git a/init/property_service.cpp b/init/property_service.cpp
index 223d34e..1a44fe3 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -33,6 +33,7 @@
 #include <sys/types.h>
 #include <sys/un.h>
 #include <unistd.h>
+#include <wchar.h>
 
 #define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
 #include <sys/_system_properties.h>
@@ -160,6 +161,12 @@
         return PROP_ERROR_INVALID_VALUE;
     }
 
+    if (mbstowcs(nullptr, value.data(), 0) == static_cast<std::size_t>(-1)) {
+        LOG(ERROR) << "property_set(\"" << name << "\", \"" << value << "\") failed: "
+                   << "value not a UTF8 encoded string";
+        return PROP_ERROR_INVALID_VALUE;
+    }
+
     prop_info* pi = (prop_info*) __system_property_find(name.c_str());
     if (pi != nullptr) {
         // ro.* properties are actually "write-once".

init/property_service_test.cpp

diff --git a/init/property_service_test.cpp b/init/property_service_test.cpp
index 3a64e02..95dd340 100644
--- a/init/property_service_test.cpp
+++ b/init/property_service_test.cpp
@@ -21,8 +21,11 @@
 #define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
 #include <sys/_system_properties.h>
 
+#include <android-base/properties.h>
 #include <gtest/gtest.h>
 
+using android::base::SetProperty;
+
 namespace android {
 namespace init {
 
@@ -50,5 +53,19 @@
   ASSERT_EQ(0, close(fd));
 }
 
+TEST(property_service, non_utf8_value) {
+    ASSERT_TRUE(SetProperty("property_service_utf8_test", "base_success"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\x80"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xC2\x01"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xE0\xFF"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xE0\xA0\xFF"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xF0\x01\xFF"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xF0\x90\xFF"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xF0\x90\x80\xFF"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "\xF0\x90\x80"));
+    EXPECT_FALSE(SetProperty("property_service_utf8_test", "ab\xF0\x90\x80\x80qe\xF0\x90\x80"));
+    EXPECT_TRUE(SetProperty("property_service_utf8_test", "\xF0\x90\x80\x80"));
+}
+
 }  // namespace init
 }  // namespace android