Allow invoking the linker on an executable.
The executable can be inside a zip file using the same syntax used for
shared objects: path.zip!/libentry.so.
The linker currently requires an absolute path. This restriction could be
loosened, but it didn't seem important? If it allowed non-absolute paths,
we'd need to decide how to handle:
- foo/bar (relative to CWD?)
- foo (search PATH / LD_LIBRARY_PATH, or also relative to CWD?)
- foo.zip!/bar (normalize_path() requires an absolute path)
The linker adjusts the argc/argv passed to main() and to constructor
functions to hide the initial linker argument, but doesn't adjust the auxv
vector or files like /proc/self/{exe,cmdline,auxv,stat}. Those files will
report that the kernel loaded the linker as an executable.
I think the linker_logger.cpp change guarding against (g_argv == NULL)
isn't actually necessary, but it seemed like a good idea given that I'm
delaying initialization of g_argv until after C++ constructors have run.
Bug: http://b/112050209
Test: bionic unit tests
Change-Id: I846faf98b16fd34218946f6167e8b451897debe5
diff --git a/tests/libs/Android.bp b/tests/libs/Android.bp
index 2d35c51..5c4eb42 100644
--- a/tests/libs/Android.bp
+++ b/tests/libs/Android.bp
@@ -852,3 +852,19 @@
defaults: ["bionic_testlib_defaults"],
srcs: ["ld_config_test_helper_lib3.cpp"],
}
+
+cc_test {
+ name: "exec_linker_helper",
+ host_supported: false,
+ defaults: ["bionic_testlib_defaults"],
+ srcs: ["exec_linker_helper.cpp"],
+ shared_libs: ["exec_linker_helper_lib"],
+ ldflags: ["-Wl,--rpath,${ORIGIN}/.."],
+}
+
+cc_test_library {
+ name: "exec_linker_helper_lib",
+ host_supported: false,
+ defaults: ["bionic_testlib_defaults"],
+ srcs: ["exec_linker_helper_lib.cpp"],
+}
diff --git a/tests/libs/Android.build.dlext_testzip.mk b/tests/libs/Android.build.dlext_testzip.mk
index 62ed4c7..19fd64b 100644
--- a/tests/libs/Android.build.dlext_testzip.mk
+++ b/tests/libs/Android.build.dlext_testzip.mk
@@ -32,7 +32,9 @@
my_shared_libs := \
$(call intermediates-dir-for,SHARED_LIBRARIES,libdlext_test_zip,,,$(bionic_2nd_arch_prefix))/libdlext_test_zip.so \
- $(call intermediates-dir-for,SHARED_LIBRARIES,libatest_simple_zip,,,$(bionic_2nd_arch_prefix))/libatest_simple_zip.so
+ $(call intermediates-dir-for,SHARED_LIBRARIES,libatest_simple_zip,,,$(bionic_2nd_arch_prefix))/libatest_simple_zip.so \
+ $(call intermediates-dir-for,NATIVE_TESTS,exec_linker_helper,,,$(bionic_2nd_arch_prefix))/exec_linker_helper \
+ $(call intermediates-dir-for,SHARED_LIBRARIES,exec_linker_helper_lib,,,$(bionic_2nd_arch_prefix))/exec_linker_helper_lib.so
$(LOCAL_BUILT_MODULE): PRIVATE_SHARED_LIBS := $(my_shared_libs)
$(LOCAL_BUILT_MODULE): $(my_shared_libs) $(BIONIC_TESTS_ZIPALIGN)
diff --git a/tests/libs/exec_linker_helper.cpp b/tests/libs/exec_linker_helper.cpp
new file mode 100644
index 0000000..01a61e0
--- /dev/null
+++ b/tests/libs/exec_linker_helper.cpp
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+
+extern "C" void _start();
+const char* helper_func();
+
+__attribute__((constructor))
+static void ctor(int argc, char* argv[]) {
+ printf("ctor: argc=%d argv[0]=%s\n", argc, argv[0]);
+}
+
+int main(int argc, char* argv[]) {
+ printf("main: argc=%d argv[0]=%s\n", argc, argv[0]);
+ printf("%s\n", helper_func());
+ return 0;
+}
diff --git a/tests/libs/exec_linker_helper_lib.cpp b/tests/libs/exec_linker_helper_lib.cpp
new file mode 100644
index 0000000..b46f482
--- /dev/null
+++ b/tests/libs/exec_linker_helper_lib.cpp
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+// Verify that the linker can find exec_linker_helper_lib.so using the
+// executable's $ORIGIN runpath, even when the executable is inside a zip file.
+
+const char* helper_func() {
+ return "helper_func called";
+}