Merge "msm: camera: Fix Use after free bug in msm_vb2.c"

drivers/media/platform/msm/ais/msm.c

@@ -283,22 +283,47 @@ void msm_delete_stream(unsigned int session_id, unsigned int stream_id)
 	struct msm_session *session = NULL;
 	struct msm_stream  *stream = NULL;
 	unsigned long flags;
+	int try_count = 0;
 
 	session = msm_queue_find(msm_session_q, struct msm_session,
 		list, __msm_queue_find_session, &session_id);
+
 	if (!session)
 		return;
 
-	stream = msm_queue_find(&session->stream_q, struct msm_stream,
-		list, __msm_queue_find_stream, &stream_id);
-	if (!stream)
-		return;
-	spin_lock_irqsave(&(session->stream_q.lock), flags);
-	list_del_init(&stream->list);
-	session->stream_q.len--;
-	kfree(stream);
-	stream = NULL;
-	spin_unlock_irqrestore(&(session->stream_q.lock), flags);
+	while (1) {
+
+		if (try_count > 5) {
+			pr_err("%s : not able to delete stream %d\n",
+				__func__, __LINE__);
+			break;
+		}
+
+		write_lock(&session->stream_rwlock);
+		try_count++;
+		stream = msm_queue_find(&session->stream_q, struct msm_stream,
+			list, __msm_queue_find_stream, &stream_id);
+
+		if (!stream) {
+			write_unlock(&session->stream_rwlock);
+			return;
+		}
+
+		if (msm_vb2_get_stream_state(stream) != 1) {
+			write_unlock(&session->stream_rwlock);
+			continue;
+		}
+
+		spin_lock_irqsave(&(session->stream_q.lock), flags);
+		list_del_init(&stream->list);
+		session->stream_q.len--;
+		kfree(stream);
+		stream = NULL;
+		spin_unlock_irqrestore(&(session->stream_q.lock), flags);
+		write_unlock(&session->stream_rwlock);
+		break;
+	}
+
 }
 EXPORT_SYMBOL(msm_delete_stream);
 
@@ -446,6 +471,7 @@ int msm_create_session(unsigned int session_id, struct video_device *vdev)
 	mutex_init(&session->lock);
 	mutex_init(&session->lock_q);
 	mutex_init(&session->close_lock);
+	rwlock_init(&session->stream_rwlock);
 	return 0;
 }
 EXPORT_SYMBOL(msm_create_session);
@@ -1040,17 +1066,25 @@ static struct v4l2_file_operations msm_fops = {
 #endif
 };
 
-struct msm_stream *msm_get_stream(unsigned int session_id,
-	unsigned int stream_id)
+struct msm_session *msm_get_session(unsigned int session_id)
 {
 	struct msm_session *session;
-	struct msm_stream *stream;
 
 	session = msm_queue_find(msm_session_q, struct msm_session,
 		list, __msm_queue_find_session, &session_id);
 	if (!session)
 		return ERR_PTR(-EINVAL);
 
+	return session;
+}
+EXPORT_SYMBOL(msm_get_session);
+
+
+struct msm_stream *msm_get_stream(struct msm_session *session,
+	unsigned int stream_id)
+{
+	struct msm_stream *stream;
+
 	stream = msm_queue_find(&session->stream_q, struct msm_stream,
 		list, __msm_queue_find_stream, &stream_id);
 
@@ -1108,6 +1142,34 @@ struct msm_stream *msm_get_stream_from_vb2q(struct vb2_queue *q)
 }
 EXPORT_SYMBOL(msm_get_stream_from_vb2q);
 
+struct msm_session *msm_get_session_from_vb2q(struct vb2_queue *q)
+{
+	struct msm_session *session;
+	struct msm_stream *stream;
+	unsigned long flags1;
+	unsigned long flags2;
+
+	spin_lock_irqsave(&msm_session_q->lock, flags1);
+	list_for_each_entry(session, &(msm_session_q->list), list) {
+		spin_lock_irqsave(&(session->stream_q.lock), flags2);
+		list_for_each_entry(
+			stream, &(session->stream_q.list), list) {
+			if (stream->vb2_q == q) {
+				spin_unlock_irqrestore
+					(&(session->stream_q.lock), flags2);
+				spin_unlock_irqrestore
+					(&msm_session_q->lock, flags1);
+				return session;
+			}
+		}
+		spin_unlock_irqrestore(&(session->stream_q.lock), flags2);
+	}
+	spin_unlock_irqrestore(&msm_session_q->lock, flags1);
+	return NULL;
+}
+EXPORT_SYMBOL(msm_get_session_from_vb2q);
+
+
 #ifdef CONFIG_COMPAT
 long msm_copy_camera_private_ioctl_args(unsigned long arg,
 	struct msm_camera_private_ioctl_arg *k_ioctl,

drivers/media/platform/msm/ais/msm.h

@@ -114,6 +114,7 @@ struct msm_session {
 	struct mutex lock;
 	struct mutex lock_q;
 	struct mutex close_lock;
+	rwlock_t stream_rwlock;
 };
 
 static inline bool msm_is_daemon_present(void)
@@ -131,11 +132,13 @@ int msm_create_stream(unsigned int session_id,
 void msm_delete_stream(unsigned int session_id, unsigned int stream_id);
 int  msm_create_command_ack_q(unsigned int session_id, unsigned int stream_id);
 void msm_delete_command_ack_q(unsigned int session_id, unsigned int stream_id);
-struct msm_stream *msm_get_stream(unsigned int session_id,
+struct msm_session *msm_get_session(unsigned int session_id);
+struct msm_stream *msm_get_stream(struct msm_session *session,
 	unsigned int stream_id);
 struct vb2_queue *msm_get_stream_vb2q(unsigned int session_id,
 	unsigned int stream_id);
 struct msm_stream *msm_get_stream_from_vb2q(struct vb2_queue *q);
+struct msm_session *msm_get_session_from_vb2q(struct vb2_queue *q);
 struct msm_session *msm_session_find(unsigned int session_id);
 #ifdef CONFIG_COMPAT
 long msm_copy_camera_private_ioctl_args(unsigned long arg,

drivers/media/platform/msm/ais/msm_vb2/msm_vb2.c

@@ -44,17 +44,25 @@ static int msm_vb2_queue_setup(struct vb2_queue *q,
 static int msm_vb2_buf_init(struct vb2_buffer *vb)
 {
 	struct msm_stream *stream;
+	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2_buf;
 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 
+	session = msm_get_session_from_vb2q(vb->vb2_queue);
+	if (IS_ERR_OR_NULL(session))
+		return -EINVAL;
+
+	read_lock(&session->stream_rwlock);
+
 	stream = msm_get_stream_from_vb2q(vb->vb2_queue);
 	if (!stream) {
 		pr_err("%s: Couldn't find stream\n", __func__);
+		read_unlock(&session->stream_rwlock);
 		return -EINVAL;
 	}
 	msm_vb2_buf = container_of(vbuf, struct msm_vb2_buffer, vb2_v4l2_buf);
 	msm_vb2_buf->in_freeq = 0;
-
+	read_unlock(&session->stream_rwlock);
 	return 0;
 }
 
@@ -62,6 +70,7 @@ static void msm_vb2_buf_queue(struct vb2_buffer *vb)
 {
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
+	struct msm_session *session;
 	unsigned long flags;
 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
 
@@ -71,21 +80,30 @@ static void msm_vb2_buf_queue(struct vb2_buffer *vb)
 		return;
 	}
 
+	session = msm_get_session_from_vb2q(vb->vb2_queue);
+	if (IS_ERR_OR_NULL(session))
+		return;
+
+	read_lock(&session->stream_rwlock);
+
 	stream = msm_get_stream_from_vb2q(vb->vb2_queue);
 	if (!stream) {
 		pr_err("%s:%d] NULL stream", __func__, __LINE__);
+		read_unlock(&session->stream_rwlock);
 		return;
 	}
 
 	spin_lock_irqsave(&stream->stream_lock, flags);
 	list_add_tail(&msm_vb2->list, &stream->queued_list);
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 }
 
 static void msm_vb2_buf_finish(struct vb2_buffer *vb)
 {
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
+	struct msm_session *session;
 	unsigned long flags;
 	struct msm_vb2_buffer *msm_vb2_entry, *temp;
 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
@@ -96,9 +114,16 @@ static void msm_vb2_buf_finish(struct vb2_buffer *vb)
 		return;
 	}
 
+	session = msm_get_session_from_vb2q(vb->vb2_queue);
+	if (IS_ERR_OR_NULL(session))
+		return;
+
+	read_lock(&session->stream_rwlock);
+
 	stream = msm_get_stream_from_vb2q(vb->vb2_queue);
 	if (!stream) {
 		pr_err("%s:%d] NULL stream", __func__, __LINE__);
+		read_unlock(&session->stream_rwlock);
 		return;
 	}
 
@@ -111,18 +136,27 @@ static void msm_vb2_buf_finish(struct vb2_buffer *vb)
 		}
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 }
 
 static void msm_vb2_stop_stream(struct vb2_queue *q)
 {
 	struct msm_vb2_buffer *msm_vb2, *temp;
 	struct msm_stream *stream;
+	struct msm_session *session;
 	unsigned long flags;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf;
 
+	session = msm_get_session_from_vb2q(q);
+	if (IS_ERR_OR_NULL(session))
+		return;
+
+	read_lock(&session->stream_rwlock);
+
 	stream = msm_get_stream_from_vb2q(q);
 	if (!stream) {
 		pr_err_ratelimited("%s:%d] NULL stream", __func__, __LINE__);
+		read_unlock(&session->stream_rwlock);
 		return;
 	}
 
@@ -142,8 +176,28 @@ static void msm_vb2_stop_stream(struct vb2_queue *q)
 		msm_vb2->in_freeq = 0;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 }
 
+int msm_vb2_get_stream_state(struct msm_stream *stream)
+{
+	struct msm_vb2_buffer *msm_vb2, *temp;
+	unsigned long flags;
+	int rc = 1;
+
+	spin_lock_irqsave(&stream->stream_lock, flags);
+	list_for_each_entry_safe(msm_vb2, temp, &(stream->queued_list), list) {
+		if (msm_vb2->in_freeq != 0) {
+			rc = 0;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	return rc;
+}
+EXPORT_SYMBOL(msm_vb2_get_stream_state);
+
+
 static struct vb2_ops msm_vb2_get_q_op = {
 	.queue_setup	= msm_vb2_queue_setup,
 	.buf_init	= msm_vb2_buf_init,
@@ -199,13 +253,22 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf(int session_id,
 {
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
+	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2 = NULL;
 	unsigned long flags;
 
-	stream = msm_get_stream(session_id, stream_id);
-	if (IS_ERR_OR_NULL(stream))
+	session = msm_get_session(session_id);
+	if (IS_ERR_OR_NULL(session))
 		return NULL;
 
+	read_lock(&session->stream_rwlock);
+
+	stream = msm_get_stream(session, stream_id);
+	if (IS_ERR_OR_NULL(stream)) {
+		read_unlock(&session->stream_rwlock);
+		return NULL;
+	}
+
 	spin_lock_irqsave(&stream->stream_lock, flags);
 
 	if (!stream->vb2_q) {
@@ -228,6 +291,7 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf(int session_id,
 	vb2_v4l2_buf = NULL;
 end:
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 	return vb2_v4l2_buf;
 }
 
@@ -236,13 +300,23 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf_by_idx(int session_id,
 {
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
+	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2 = NULL;
 	unsigned long flags;
 
-	stream = msm_get_stream(session_id, stream_id);
-	if (IS_ERR_OR_NULL(stream))
+	session = msm_get_session(session_id);
+	if (IS_ERR_OR_NULL(session))
 		return NULL;
 
+	read_lock(&session->stream_rwlock);
+
+	stream = msm_get_stream(session, stream_id);
+
+	if (IS_ERR_OR_NULL(stream)) {
+		read_unlock(&session->stream_rwlock);
+		return NULL;
+	}
+
 	spin_lock_irqsave(&stream->stream_lock, flags);
 
 	if (!stream->vb2_q) {
@@ -263,6 +337,7 @@ static struct vb2_v4l2_buffer *msm_vb2_get_buf_by_idx(int session_id,
 	vb2_v4l2_buf = NULL;
 end:
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 	return vb2_v4l2_buf;
 }
 
@@ -270,15 +345,24 @@ static int msm_vb2_put_buf(struct vb2_v4l2_buffer *vb, int session_id,
 				unsigned int stream_id)
 {
 	struct msm_stream *stream;
+	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
 	int rc = 0;
 	unsigned long flags;
 
-	stream = msm_get_stream(session_id, stream_id);
-	if (IS_ERR_OR_NULL(stream))
+	session = msm_get_session(session_id);
+	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
 
+	read_lock(&session->stream_rwlock);
+
+	stream = msm_get_stream(session, stream_id);
+	if (IS_ERR_OR_NULL(stream)) {
+		read_unlock(&session->stream_rwlock);
+		return -EINVAL;
+	}
+
 	spin_lock_irqsave(&stream->stream_lock, flags);
 	if (vb) {
 		list_for_each_entry(msm_vb2, &(stream->queued_list), list) {
@@ -306,6 +390,7 @@ static int msm_vb2_put_buf(struct vb2_v4l2_buffer *vb, int session_id,
 		rc = -EINVAL;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 	return rc;
 }
 
@@ -317,11 +402,21 @@ static int msm_vb2_buf_done(struct vb2_v4l2_buffer *vb, int session_id,
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
+	struct msm_session *session;
 	int rc = 0;
 
-	stream = msm_get_stream(session_id, stream_id);
-	if (IS_ERR_OR_NULL(stream))
+	session = msm_get_session(session_id);
+	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
+
+	read_lock(&session->stream_rwlock);
+
+	stream = msm_get_stream(session, stream_id);
+	if (IS_ERR_OR_NULL(stream)) {
+		read_unlock(&session->stream_rwlock);
+		return -EINVAL;
+	}
+
 	spin_lock_irqsave(&stream->stream_lock, flags);
 	if (vb) {
 		list_for_each_entry(msm_vb2, &(stream->queued_list), list) {
@@ -353,6 +448,7 @@ static int msm_vb2_buf_done(struct vb2_v4l2_buffer *vb, int session_id,
 		rc = -EINVAL;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 	return rc;
 }
 
@@ -361,14 +457,23 @@ long msm_vb2_return_buf_by_idx(int session_id, unsigned int stream_id,
 {
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
+	struct msm_session *session;
 	struct msm_vb2_buffer *msm_vb2 = NULL;
 	unsigned long flags;
 	long rc = -EINVAL;
 
-	stream = msm_get_stream(session_id, stream_id);
-	if (IS_ERR_OR_NULL(stream))
+	session = msm_get_session(session_id);
+	if (IS_ERR_OR_NULL(session))
 		return rc;
 
+	read_lock(&session->stream_rwlock);
+
+	stream = msm_get_stream(session, stream_id);
+	if (IS_ERR_OR_NULL(stream)) {
+		read_unlock(&session->stream_rwlock);
+		return -EINVAL;
+	}
+
 	spin_lock_irqsave(&stream->stream_lock, flags);
 
 	if (!stream->vb2_q) {
@@ -394,6 +499,7 @@ long msm_vb2_return_buf_by_idx(int session_id, unsigned int stream_id,
 
 end:
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 	return rc;
 }
 EXPORT_SYMBOL(msm_vb2_return_buf_by_idx);
@@ -404,10 +510,20 @@ static int msm_vb2_flush_buf(int session_id, unsigned int stream_id)
 	struct msm_vb2_buffer *msm_vb2;
 	struct msm_stream *stream;
 	struct vb2_v4l2_buffer *vb2_v4l2_buf = NULL;
+	struct msm_session *session;
 
-	stream = msm_get_stream(session_id, stream_id);
-	if (IS_ERR_OR_NULL(stream))
+	session = msm_get_session(session_id);
+	if (IS_ERR_OR_NULL(session))
 		return -EINVAL;
+
+	read_lock(&session->stream_rwlock);
+
+	stream = msm_get_stream(session, stream_id);
+	if (IS_ERR_OR_NULL(stream)) {
+		read_unlock(&session->stream_rwlock);
+		return -EINVAL;
+	}
+
 	spin_lock_irqsave(&stream->stream_lock, flags);
 	list_for_each_entry(msm_vb2, &(stream->queued_list), list) {
 		vb2_v4l2_buf = &(msm_vb2->vb2_v4l2_buf);
@@ -416,6 +532,7 @@ static int msm_vb2_flush_buf(int session_id, unsigned int stream_id)
 		msm_vb2->in_freeq = 0;
 	}
 	spin_unlock_irqrestore(&stream->stream_lock, flags);
+	read_unlock(&session->stream_rwlock);
 	return 0;
 }
 

drivers/media/platform/msm/ais/msm_vb2/msm_vb2.h

@@ -68,5 +68,6 @@ struct vb2_mem_ops *msm_vb2_get_q_mem_ops(void);
 int msm_vb2_request_cb(struct msm_sd_req_vb2_q *req_sd);
 long msm_vb2_return_buf_by_idx(int session_id, unsigned int stream_id,
 	uint32_t index);
+int msm_vb2_get_stream_state(struct msm_stream *stream);
 
 #endif /*_MSM_VB_H */