diff --git a/include/libcamera/internal/framebuffer.h b/include/libcamera/internal/framebuffer.h
index 7e96100b6c..466ddc1b73 100644
--- a/include/libcamera/internal/framebuffer.h
+++ b/include/libcamera/internal/framebuffer.h
@@ -19,6 +19,8 @@
 
 namespace libcamera {
 
+class Stream;
+
 class FrameBuffer::Private : public Extensible::Private
 {
 	LIBCAMERA_DECLARE_PUBLIC(FrameBuffer)
@@ -39,6 +41,8 @@ public:
 
 	FrameMetadata &metadata() { return metadata_; }
 
+	const Stream *stream_ = nullptr;
+
 private:
 	std::vector<Plane> planes_;
 	FrameMetadata metadata_;
diff --git a/src/libcamera/framebuffer.cpp b/src/libcamera/framebuffer.cpp
index 4f23df6482..baa298a8e3 100644
--- a/src/libcamera/framebuffer.cpp
+++ b/src/libcamera/framebuffer.cpp
@@ -232,6 +232,14 @@ FrameBuffer::Private::~Private()
  * \brief Retrieve the dynamic metadata
  * \return Dynamic metadata for the frame contained in the buffer
  */
+
+/**
+ * \var FrameBuffer::Private::stream_
+ * \brief The Stream the buffer belongs to
+ *
+ * This member designates the Stream of the Camera that the buffer belongs
+ * to at the moment.
+ */
 #endif /* __DOXYGEN_PUBLIC__ */
 
 /**
diff --git a/src/libcamera/request.cpp b/src/libcamera/request.cpp
index b1a81e36ef..278d993445 100644
--- a/src/libcamera/request.cpp
+++ b/src/libcamera/request.cpp
@@ -107,10 +107,13 @@ bool Request::Private::completeBuffer(FrameBuffer *buffer)
 	Request *request = LIBCAMERA_O_PTR();
 	camera_->bufferCompleted.emit(request, buffer);
 
+	ASSERT(request->findBuffer(buffer->_d()->stream_) == buffer);
+
 	int ret = pending_.erase(buffer);
 	ASSERT(ret == 1);
 
 	buffer->_d()->setRequest(nullptr);
+	buffer->_d()->stream_ = nullptr;
 
 	if (buffer->metadata().status == FrameMetadata::FrameCancelled)
 		cancelled_ = true;
@@ -147,6 +150,7 @@ void Request::Private::doCancelRequest()
 		buffer->_d()->cancel();
 		camera_->bufferCompleted.emit(request, buffer);
 		buffer->_d()->setRequest(nullptr);
+		buffer->_d()->stream_ = nullptr;
 	}
 
 	cancelled_ = true;
@@ -495,6 +499,7 @@ int Request::addBuffer(const Stream *stream, FrameBuffer *buffer,
 	}
 
 	buffer->_d()->setRequest(this);
+	buffer->_d()->stream_ = stream;
 	_d()->pending_.insert(buffer);
 
 	if (fence && fence->isValid())