[PATCH] virtio_console: Put device on failure

[Michail Tatas <michail.tatas@gmail.com>]

If dma_alloc_coherent() fails, the buffer is freed but not the
reference which is acquired before calling dma_alloc_coherent().
Fix by calling put_device in the error path.

Fixes: 1b6370463e88 ("virtio_console: Add support for remoteproc serial")
Signed-off-by: Michail Tatas <michail.tatas@gmail.com>
---
 drivers/char/virtio_console.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 62eecfa61646..de83a8a61a8f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -451,18 +451,22 @@ static struct port_buffer *alloc_buf(struct virtio_device *vdev, size_t buf_size
 		/* Increase device refcnt to avoid freeing it */
 		get_device(buf->dev);
 		buf->buf = dma_alloc_coherent(buf->dev, buf_size, &buf->dma, gfp);
+		if (!buf->buf)
+			goto free_buf_and_put_dev;
 	} else {
 		buf->dev = NULL;
 		buf->buf = kmalloc(buf_size, gfp);
+		if (!buf->buf)
+			goto free_buf;
 	}
 
-	if (!buf->buf)
-		goto free_buf;
 	buf->len = 0;
 	buf->offset = 0;
 	buf->size = buf_size;
 	return buf;
 
+free_buf_and_put_dev:
+	put_device(buf->dev);
 free_buf:
 	kfree(buf);
 fail:
-- 
2.43.0