diff --git a/adb/apex/apex_manifest.json b/adb/apex/apex_manifest.json
index b1994608d..4a07bdcc5 100644
--- a/adb/apex/apex_manifest.json
+++ b/adb/apex/apex_manifest.json
@@ -1,4 +1,4 @@
 {
   "name": "com.android.adbd",
-  "version": 300900600
+  "version": 300900700
 }
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 0739fab74..4178349ed 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -1846,7 +1846,7 @@ auto SnapshotManager::OpenFile(const std::string& file, int lock_flags)
         PLOG(ERROR) << "Open failed: " << file;
         return nullptr;
     }
-    if (lock_flags != 0 && flock(fd, lock_flags) < 0) {
+    if (lock_flags != 0 && TEMP_FAILURE_RETRY(flock(fd, lock_flags)) < 0) {
         PLOG(ERROR) << "Acquire flock failed: " << file;
         return nullptr;
     }
@@ -1857,7 +1857,7 @@ auto SnapshotManager::OpenFile(const std::string& file, int lock_flags)
 }
 
 SnapshotManager::LockedFile::~LockedFile() {
-    if (flock(fd_, LOCK_UN) < 0) {
+    if (TEMP_FAILURE_RETRY(flock(fd_, LOCK_UN)) < 0) {
         PLOG(ERROR) << "Failed to unlock file: " << path_;
     }
 }
@@ -2516,7 +2516,19 @@ std::unique_ptr<AutoDevice> SnapshotManager::EnsureMetadataMounted() {
         LOG(INFO) << "EnsureMetadataMounted does nothing in Android mode.";
         return std::unique_ptr<AutoUnmountDevice>(new AutoUnmountDevice());
     }
-    return AutoUnmountDevice::New(device_->GetMetadataDir());
+    auto ret = AutoUnmountDevice::New(device_->GetMetadataDir());
+    if (ret == nullptr) return nullptr;
+
+    // In rescue mode, it is possible to erase and format metadata, but /metadata/ota is not
+    // created to execute snapshot updates. Hence, subsequent calls is likely to fail because
+    // Lock*() fails. By failing early and returning nullptr here, update_engine_sideload can
+    // treat this case as if /metadata is not mounted.
+    if (!LockShared()) {
+        LOG(WARNING) << "/metadata is mounted, but errors occur when acquiring a shared lock. "
+                        "Subsequent calls to SnapshotManager will fail. Unmounting /metadata now.";
+        return nullptr;
+    }
+    return ret;
 }
 
 bool SnapshotManager::HandleImminentDataWipe(const std::function<void()>& callback) {