From f643b354fefea310981afcd524832e9c52039826 Mon Sep 17 00:00:00 2001
From: Jingwen Chen <jingwen@google.com>
Date: Thu, 16 Mar 2023 16:22:25 +0000
Subject: [PATCH] Make the host_init_verifier init.rc parser follow symlinks.

Bazel's intermediates/inputs are symlinks in its execution root, unlike Soong.

e.g.

$ file $(readlink -f out/bazel/output/execroot/__main__/packages/modules/adb/apex/adbd.rc)
/usr/local/google/home/jingwen/aosp/master-with-phones/packages/modules/adb/apex/adbd.rc:
ASCII text

Test: presubmits
Change-Id: I3977a37ee989e07bee56abb019a21055b8cef567
---
 init/fuzzer/init_parser_fuzzer.cpp | 2 +-
 init/host_init_verifier.cpp        | 4 +++-
 init/parser.cpp                    | 4 ++--
 init/parser.h                      | 2 +-
 4 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/init/fuzzer/init_parser_fuzzer.cpp b/init/fuzzer/init_parser_fuzzer.cpp
index e6a78a2c4..dc764650a 100644
--- a/init/fuzzer/init_parser_fuzzer.cpp
+++ b/init/fuzzer/init_parser_fuzzer.cpp
@@ -125,7 +125,7 @@ void InitParserFuzzer::InvokeParser() {
     std::string path = fdp_.ConsumeBool() ? fdp_.PickValueInArray(kValidPaths)
                                           : fdp_.ConsumeRandomLengthString(kMaxBytes);
     parser.ParseConfig(path);
-    parser.ParseConfigFileInsecure(path);
+    parser.ParseConfigFileInsecure(path, false /* follow_symlinks */);
 }
 
 void InitParserFuzzer::Process() {
diff --git a/init/host_init_verifier.cpp b/init/host_init_verifier.cpp
index db127d3f2..f070776ec 100644
--- a/init/host_init_verifier.cpp
+++ b/init/host_init_verifier.cpp
@@ -326,7 +326,9 @@ int main(int argc, char** argv) {
             }
         }
     } else {
-        if (!parser.ParseConfigFileInsecure(*argv)) {
+        if (!parser.ParseConfigFileInsecure(*argv, true /* follow_symlinks */)) {
+          // Follow symlinks as inputs during build execution in Bazel's
+          // execution root are symlinks, unlike Soong or Make.
             LOG(ERROR) << "Failed to open init rc script '" << *argv << "'";
             return EXIT_FAILURE;
         }
diff --git a/init/parser.cpp b/init/parser.cpp
index adb41add1..8c0bb2b68 100644
--- a/init/parser.cpp
+++ b/init/parser.cpp
@@ -131,9 +131,9 @@ void Parser::ParseData(const std::string& filename, std::string* data) {
     }
 }
 
-bool Parser::ParseConfigFileInsecure(const std::string& path) {
+bool Parser::ParseConfigFileInsecure(const std::string& path, bool follow_symlinks = false) {
     std::string config_contents;
-    if (!android::base::ReadFileToString(path, &config_contents)) {
+    if (!android::base::ReadFileToString(path, &config_contents, follow_symlinks)) {
         return false;
     }
 
diff --git a/init/parser.h b/init/parser.h
index 980ae0ccb..8e5bca773 100644
--- a/init/parser.h
+++ b/init/parser.h
@@ -77,7 +77,7 @@ class Parser {
     void AddSingleLineParser(const std::string& prefix, LineCallback callback);
 
     // Host init verifier check file permissions.
-    bool ParseConfigFileInsecure(const std::string& path);
+    bool ParseConfigFileInsecure(const std::string& path, bool follow_symlinks);
 
     size_t parse_error_count() const { return parse_error_count_; }