ART: Weaken dex file verifier abstract check

We decided to not reject dex files with non-abstract classes containing
abstract methods (even though that's broken code). Just log a warning
instead.

Reported by Nikolay Serdjuk.

Bug: 26143249
Change-Id: Iaf981dba70c7c4b9c844ad9f2806278072e3ed52

4 files changed, 28 insertions, 4 deletions

diff --git a/runtime/dex_file_verifier.cc b/runtime/dex_file_verifier.cc
index 440d696ea9..727f4fc659 100644
--- a/runtime/dex_file_verifier.cc
+++ b/runtime/dex_file_verifier.cc
@@ -2508,11 +2508,12 @@ bool DexFileVerifier::CheckMethodAccessFlags(uint32_t method_index,
                                   method_access_flags);
         return false;
       }
-      // Abstract methods must be in an abstract class or interface.
+      // Abstract methods should be in an abstract class or interface.
       if ((class_access_flags & (kAccInterface | kAccAbstract)) == 0) {
-        *error_msg = StringPrintf("Method %" PRIu32 " is abstract, but the declaring class "
-                                  "is neither abstract nor an interface", method_index);
-        return false;
+        LOG(WARNING) << "Method " << PrettyMethod(method_index, *dex_file_)
+                     << " is abstract, but the declaring class is neither abstract nor an "
+                     << "interface in dex file "
+                     << dex_file_->GetLocation();
       }
     }
     // Interfaces are special.
diff --git a/test/800-smali/expected.txt b/test/800-smali/expected.txt
index ebefeea405..27f5b5d552 100644
--- a/test/800-smali/expected.txt
+++ b/test/800-smali/expected.txt
@@ -48,4 +48,5 @@ b/23502994 (if-eqz)
 b/23502994 (check-cast)
 b/25494456
 b/21869691
+b/26143249
 Done!
diff --git a/test/800-smali/smali/b_26143249.smali b/test/800-smali/smali/b_26143249.smali
new file mode 100644
index 0000000000..aa69e84bfa
--- /dev/null
+++ b/test/800-smali/smali/b_26143249.smali
@@ -0,0 +1,20 @@
+# Make sure we accept non-abstract classes with abstract members.
+
+.class public LB26143249;
+
+.super Ljava/lang/Object;
+
+.method public constructor <init>()V
+    .registers 1
+    invoke-direct {p0}, Ljava/lang/Object;-><init>()V
+    return-void
+.end method
+
+.method public run()V
+    .registers 1
+    invoke-virtual {p0}, LB26143249;->abs()V
+    return-void
+.end method
+
+.method public abstract abs()V
+.end method
diff --git a/test/800-smali/src/Main.java b/test/800-smali/src/Main.java
index 3b62a46fd3..cc3b0b44f9 100644
--- a/test/800-smali/src/Main.java
+++ b/test/800-smali/src/Main.java
@@ -141,6 +141,8 @@ public class Main {
                 null));
         testCases.add(new TestCase("b/21869691", "B21869691A", "run", null,
                 new IncompatibleClassChangeError(), null));
+        testCases.add(new TestCase("b/26143249", "B26143249", "run", null,
+                new AbstractMethodError(), null));
     }
 
     public void runTests() {