diff --git a/bootstat/bootstat.cpp b/bootstat/bootstat.cpp
index d402bf1..d476d36 100644
--- a/bootstat/bootstat.cpp
+++ b/bootstat/bootstat.cpp
@@ -499,7 +499,7 @@
 }
 
 // Canonical list of supported primary reboot reasons.
-const std::vector<const std::string> knownReasons = {
+const std::vector<std::string> knownReasons = {
     // clang-format off
     // kernel
     "watchdog",
diff --git a/fs_mgr/fs_mgr_overlayfs_mount.cpp b/fs_mgr/fs_mgr_overlayfs_mount.cpp
index bd0fcfd..b63b9e7 100644
--- a/fs_mgr/fs_mgr_overlayfs_mount.cpp
+++ b/fs_mgr/fs_mgr_overlayfs_mount.cpp
@@ -74,7 +74,7 @@
     return android::gsi::IsGsiRunning();
 }
 
-std::vector<const std::string> OverlayMountPoints() {
+std::vector<std::string> OverlayMountPoints() {
     // Never fallback to legacy cache mount point if within a DSU system,
     // because running a DSU system implies the device supports dynamic
     // partitions, which means legacy cache mustn't be used.
diff --git a/fs_mgr/fs_mgr_overlayfs_mount.h b/fs_mgr/fs_mgr_overlayfs_mount.h
index 98b9007..f941ab1 100644
--- a/fs_mgr/fs_mgr_overlayfs_mount.h
+++ b/fs_mgr/fs_mgr_overlayfs_mount.h
@@ -54,7 +54,7 @@
 bool OverlayfsSetupAllowed(bool verbose = false);
 bool MountScratch(const std::string& device_path, bool readonly = false);
 bool fs_mgr_overlayfs_umount_scratch();
-std::vector<const std::string> OverlayMountPoints();
+std::vector<std::string> OverlayMountPoints();
 bool fs_mgr_overlayfs_already_mounted(const std::string& mount_point, bool overlay_only = true);
 bool fs_mgr_wants_overlayfs(android::fs_mgr::FstabEntry* entry);
 android::fs_mgr::Fstab fs_mgr_overlayfs_candidate_list(const android::fs_mgr::Fstab& fstab);
diff --git a/fs_mgr/fs_mgr_vendor_overlay.cpp b/fs_mgr/fs_mgr_vendor_overlay.cpp
index 6b742e5..6687283 100644
--- a/fs_mgr/fs_mgr_vendor_overlay.cpp
+++ b/fs_mgr/fs_mgr_vendor_overlay.cpp
@@ -36,7 +36,7 @@
 
 // The order of the list means the priority to show the files in the directory.
 // The last one has the highest priority.
-const std::vector<const std::string> kVendorOverlaySourceDirs = {
+const std::vector<std::string> kVendorOverlaySourceDirs = {
         "/system/vendor_overlay/",
         "/product/vendor_overlay/",
 };
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
index 56f7b59..6d0ae3d 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp
@@ -79,6 +79,8 @@
     std::unique_ptr<ICowWriter> CreateCowDeviceInternal();
     std::unique_ptr<ICowWriter> CreateV3Cow();
 
+    unique_fd GetCowFd() { return unique_fd{dup(cow_system_->fd)}; }
+
     std::unique_ptr<ITestHarness> harness_;
     size_t size_ = 10_MiB;
     int total_base_size_ = 0;
@@ -101,7 +103,9 @@
 #endif
 }
 
-void SnapuserdTestBase::TearDown() {}
+void SnapuserdTestBase::TearDown() {
+    cow_system_ = nullptr;
+}
 
 void SnapuserdTestBase::CreateBaseDevice() {
     total_base_size_ = (size_ * 5);
@@ -132,10 +136,7 @@
     CowOptions options;
     options.compression = "gz";
 
-    unique_fd fd(cow_system_->fd);
-    cow_system_->fd = -1;
-
-    return CreateCowWriter(2, options, std::move(fd));
+    return CreateCowWriter(2, options, GetCowFd());
 }
 
 std::unique_ptr<ICowWriter> SnapuserdTestBase::CreateV3Cow() {
@@ -151,10 +152,7 @@
     std::string path = android::base::GetExecutableDirectory();
     cow_system_ = std::make_unique<TemporaryFile>(path);
 
-    unique_fd fd(cow_system_->fd);
-    cow_system_->fd = -1;
-
-    return CreateCowWriter(3, options, std::move(fd));
+    return CreateCowWriter(3, options, GetCowFd());
 }
 
 void SnapuserdTestBase::CreateCowDevice() {