adb: Do not use fs_config unless we are root.

This enables fs_config for /data when pushing files as root. Also,
without this, adb push to /tmp fails as the shell user.

Bug: 171233429
Bug: 311263616
Change-Id: I3c75fbdceb0ce48ac340b7a181788f0e73b81d39

1 files changed, 5 insertions, 10 deletions

diff --git a/daemon/file_sync_service.cpp b/daemon/file_sync_service.cpp
index 5891d30e..a549beee 100644
--- a/daemon/file_sync_service.cpp
+++ b/daemon/file_sync_service.cpp
@@ -68,14 +68,9 @@ using android::base::Dirname;
 using android::base::Realpath;
 using android::base::StringPrintf;
 
-static bool should_use_fs_config(const std::string& path) {
-#if defined(__ANDROID__)
-    // TODO: use fs_config to configure permissions on /data too.
-    return !android::base::StartsWith(path, "/data/");
-#else
-    UNUSED(path);
-    return false;
-#endif
+static bool should_use_fs_config() {
+    // Only root has the necessary permissions to be able to apply fs_config.
+    return getuid() == 0;
 }
 
 static bool update_capabilities(const char* path, uint64_t capabilities) {
@@ -119,7 +114,7 @@ static bool secure_mkdirs(const std::string& path) {
         }
         partial_path += path_component;
 
-        if (should_use_fs_config(partial_path)) {
+        if (should_use_fs_config()) {
             adbd_fs_config(partial_path.c_str(), 1, nullptr, &uid, &gid, &mode, &capabilities);
         }
         if (adb_mkdir(partial_path.c_str(), mode) == -1) {
@@ -530,7 +525,7 @@ static bool send_impl(int s, const std::string& path, mode_t mode, CompressionTy
         uid_t uid = -1;
         gid_t gid = -1;
         uint64_t capabilities = 0;
-        if (should_use_fs_config(path) && !dry_run) {
+        if (should_use_fs_config() && !dry_run) {
             adbd_fs_config(path.c_str(), 0, nullptr, &uid, &gid, &mode, &capabilities);
         }