From 3a8130c797cd762427698f6a6245bba4c84c2e4b Mon Sep 17 00:00:00 2001
From: Jiyong Park <jiyong@google.com>
Date: Tue, 27 Jul 2021 22:42:23 +0900
Subject: [PATCH] Prohibit static executable in APEX

If a library is statically included in a static executable, it's
behavior is different from the case where the same library is statically
(or dynamically) linked to a non-static executable. To reduce the number
of test configs that we need to consider, it is required to prohibit
static executables in APEXes.

Bug: 185971244
Test: m
Change-Id: I0cd8fca669d55088e2329fef1f859eeb297502dd
---
 apex/apex.go      | 30 ++++++++++++++++++++++++++++++
 apex/apex_test.go | 30 +++++++++++++++++++++++++++---
 2 files changed, 57 insertions(+), 3 deletions(-)

diff --git a/apex/apex.go b/apex/apex.go
index 0857946ea..e8bb9b7ac 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -1696,6 +1696,7 @@ func (a *apexBundle) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	a.checkUpdatable(ctx)
 	a.checkMinSdkVersion(ctx)
 	a.checkStaticLinkingToStubLibraries(ctx)
+	a.checkStaticExecutables(ctx)
 	if len(a.properties.Tests) > 0 && !a.testApex {
 		ctx.PropertyErrorf("tests", "property allowed only in apex_test module type")
 		return
@@ -2487,6 +2488,35 @@ func (a *apexBundle) checkApexAvailability(ctx android.ModuleContext) {
 	})
 }
 
+// checkStaticExecutable ensures that executables in an APEX are not static.
+func (a *apexBundle) checkStaticExecutables(ctx android.ModuleContext) {
+	ctx.VisitDirectDepsBlueprint(func(module blueprint.Module) {
+		if ctx.OtherModuleDependencyTag(module) != executableTag {
+			return
+		}
+		if cc, ok := module.(*cc.Module); ok && cc.StaticExecutable() {
+			apex := a.ApexVariationName()
+			exec := ctx.OtherModuleName(module)
+			if isStaticExecutableAllowed(apex, exec) {
+				return
+			}
+			ctx.ModuleErrorf("executable %s is static", ctx.OtherModuleName(module))
+		}
+	})
+}
+
+// A small list of exceptions where static executables are allowed in APEXes.
+func isStaticExecutableAllowed(apex string, exec string) bool {
+	m := map[string][]string{
+		"com.android.runtime": []string{
+			"linker",
+			"linkerconfig",
+		},
+	}
+	execNames, ok := m[apex]
+	return ok && android.InList(exec, execNames)
+}
+
 // Collect information for opening IDE project files in java/jdeps.go.
 func (a *apexBundle) IDEInfo(dpInfo *android.IdeInfo) {
 	dpInfo.Deps = append(dpInfo.Deps, a.properties.Java_libs...)
diff --git a/apex/apex_test.go b/apex/apex_test.go
index f58bf6cc5..1645c9978 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -374,7 +374,6 @@ func TestBasicApex(t *testing.T) {
 			symlinks: ["foo_link_"],
 			symlink_preferred_arch: true,
 			system_shared_libs: [],
-			static_executable: true,
 			stl: "none",
 			apex_available: [ "myapex", "com.android.gki.*" ],
 		}
@@ -2494,7 +2493,6 @@ func TestFilesInSubDir(t *testing.T) {
 			srcs: ["mylib.cpp"],
 			relative_install_path: "foo/bar",
 			system_shared_libs: [],
-			static_executable: true,
 			stl: "none",
 			apex_available: [ "myapex" ],
 		}
@@ -2554,7 +2552,6 @@ func TestFilesInSubDirWhenNativeBridgeEnabled(t *testing.T) {
 			name: "mybin",
 			relative_install_path: "foo/bar",
 			system_shared_libs: [],
-			static_executable: true,
 			stl: "none",
 			apex_available: [ "myapex" ],
 			native_bridge_supported: true,
@@ -8188,6 +8185,33 @@ func TestApexJavaCoverage(t *testing.T) {
 	}
 }
 
+func TestProhibitStaticExecutable(t *testing.T) {
+	testApexError(t, `executable mybin is static`, `
+		apex {
+			name: "myapex",
+			key: "myapex.key",
+			binaries: ["mybin"],
+			min_sdk_version: "29",
+		}
+
+		apex_key {
+			name: "myapex.key",
+			public_key: "testkey.avbpubkey",
+			private_key: "testkey.pem",
+		}
+
+		cc_binary {
+			name: "mybin",
+			srcs: ["mylib.cpp"],
+			relative_install_path: "foo/bar",
+			static_executable: true,
+			system_shared_libs: [],
+			stl: "none",
+			apex_available: [ "myapex" ],
+		}
+	`)
+}
+
 func TestMain(m *testing.M) {
 	os.Exit(m.Run())
 }