From f9586e171427c1b078b4f3fe81a5729a5d21aa5c Mon Sep 17 00:00:00 2001
From: ignat10 <ignat.shikh@gmail.com>
Date: Mon, 2 Nov 2026 05:14:30 +0100
Subject: [PATCH] fix(android): prevent crash on large clipboard payload (>1MB)
 (#16767)

* Limit oversized remote clipboard text on Android

* Add write permission

* Increase MAX_CLIPBOARD_TEXT_CODE_UNITS to 1MB

* fix: revert unrelated workflow permission changes

* fix(android): address review feedback on clipboard size and exception handling

- Replace UTF-16 character count check with a serialized Parcel size check capped at 800 KB, leaving headroom for Android Binder transaction overhead.
- Wrap setPrimaryClip() in a try-catch to safely absorb direct and runtime-wrapped Binder exceptions (e.g. TransactionTooLargeException) without crashing.
- Assign lastUpdatedClipData only after a successful clipboard write to preserve consistent synchronization bookkeeping on failure.
---
 .../carriez/flutter_hbb/RdClipboardManager.kt | 25 +++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/RdClipboardManager.kt b/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/RdClipboardManager.kt
index 8c9d85028..fc50c3750 100644
--- a/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/RdClipboardManager.kt
+++ b/flutter/android/app/src/main/kotlin/com/carriez/flutter_hbb/RdClipboardManager.kt
@@ -7,6 +7,7 @@ import java.util.TimerTask
 import android.content.ClipData
 import android.content.ClipDescription
 import android.content.ClipboardManager
+import android.os.Parcel
 import android.util.Log
 import androidx.annotation.Keep
 
@@ -17,6 +18,10 @@ import hbb.MessageOuterClass.MultiClipboards
 import ffi.FFI
 
 class RdClipboardManager(private val clipboardManager: ClipboardManager) {
+    companion object {
+        private const val MAX_CLIPBOARD_PARCEL_BYTES = 800 * 1024
+    }
+
     private val logTag = "RdClipboardManager"
     private val supportedMimeTypes = arrayOf(
         ClipDescription.MIMETYPE_TEXT_PLAIN,
@@ -191,7 +196,23 @@ class RdClipboardManager(private val clipboardManager: ClipboardManager) {
             return
         }
         val clipData = ClipData(clipDescription, item)
-        lastUpdatedClipData = clipData
-        clipboardManager.setPrimaryClip(clipData)
+        val parcel = Parcel.obtain()
+        val isTooLarge = try {
+            clipData.writeToParcel(parcel, 0)
+            parcel.dataSize() > MAX_CLIPBOARD_PARCEL_BYTES
+        } finally {
+            parcel.recycle()
+        }
+        if (isTooLarge) {
+            Log.w(logTag, "Remote clipboard text is too large for Android clipboard")
+            return
+        }
+
+        try {
+            clipboardManager.setPrimaryClip(clipData)
+            lastUpdatedClipData = clipData
+        } catch (e: Exception) {
+            Log.e(logTag, "Failed to set primary clip", e)
+        }
     }
 }