diff --git a/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.cpp b/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.cpp
index 166d2c4062..b132b28d2b 100644
--- a/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.cpp
+++ b/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.cpp
@@ -73,6 +73,7 @@ RNDISDevice::RNDISDevice(usb_device device)
 		fWriteEndpoint(0),
 		fNotifyReadSem(-1),
 		fNotifyWriteSem(-1),
+		fLockWriteSem(-1),
 		fNotifyControlSem(-1),
 		fReadHeader(NULL),
 		fLinkStateChangeSem(-1),
@@ -102,6 +103,12 @@ RNDISDevice::RNDISDevice(usb_device device)
 		return;
 	}
 
+	fLockWriteSem = create_sem(1, DRIVER_NAME"_lock_write");
+	if (fNotifyWriteSem < B_OK) {
+		TRACE_ALWAYS("failed to create write lock sem\n");
+		return;
+	}
+
 	fNotifyControlSem = create_sem(0, DRIVER_NAME"_notify_control");
 	if (fNotifyControlSem < B_OK) {
 		TRACE_ALWAYS("failed to create control notify sem\n");
@@ -123,6 +130,10 @@ RNDISDevice::~RNDISDevice()
 		delete_sem(fNotifyReadSem);
 	if (fNotifyWriteSem >= B_OK)
 		delete_sem(fNotifyWriteSem);
+	if (fLockWriteSem >= B_OK)
+		delete_sem(fLockWriteSem);
+	if (fNotifyControlSem >= B_OK)
+		delete_sem(fNotifyControlSem);
 
 	if (!fRemoved)
 		gUSBModule->cancel_queued_transfers(fNotifyEndpoint);
@@ -326,6 +337,26 @@ RNDISDevice::Read(uint8 *buffer, size_t *numBytes)
 }
 
 
+class SemLocker {
+public:
+	SemLocker(sem_id sem)
+		: fSem(sem)
+	{
+		fStatus = acquire_sem(fSem);
+	}
+
+	~SemLocker()
+	{
+		if (fStatus == B_OK)
+			release_sem(fSem);
+	}
+
+	status_t fStatus;
+private:
+	sem_id fSem;
+};
+
+
 status_t
 RNDISDevice::Write(const uint8 *buffer, size_t *numBytes)
 {
@@ -348,13 +379,23 @@ RNDISDevice::Write(const uint8 *buffer, size_t *numBytes)
 	vec[1].iov_base = (void*)buffer;
 	vec[1].iov_len = *numBytes;
 
-	status_t result = gUSBModule->queue_bulk_v(fWriteEndpoint, vec, 2, _WriteCallback, this);
+	SemLocker mutex(fLockWriteSem);
+	status_t result = mutex.fStatus;
+	if (result < B_OK) {
+		*numBytes = 0;
+		return result;
+	}
+
+	result = gUSBModule->queue_bulk_v(fWriteEndpoint, vec, 2, _WriteCallback, this);
 	if (result != B_OK) {
 		*numBytes = 0;
 		return result;
 	}
 
-	result = acquire_sem_etc(fNotifyWriteSem, 1, B_CAN_INTERRUPT, 0);
+	do {
+		result = acquire_sem_etc(fNotifyWriteSem, 1, B_CAN_INTERRUPT, 0);
+	} while (result == B_INTERRUPTED);
+
 	if (result < B_OK) {
 		*numBytes = 0;
 		return result;
@@ -372,6 +413,7 @@ RNDISDevice::Write(const uint8 *buffer, size_t *numBytes)
 	}
 
 	*numBytes = fActualLengthWrite;
+
 	return B_OK;
 }
 
diff --git a/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.h b/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.h
index 60a23655a1..872739faa5 100644
--- a/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.h
+++ b/src/add-ons/kernel/drivers/network/ether/usb_rndis/RNDISDevice.h
@@ -76,6 +76,7 @@ static	void				_NotifyCallback(void *cookie, int32 status,
 		int32				fStatusWrite;
 		sem_id				fNotifyReadSem;
 		sem_id				fNotifyWriteSem;
+		sem_id				fLockWriteSem;
 		sem_id				fNotifyControlSem;
 
 		uint8				fNotifyBuffer[8];