[PATCH] virtio_console: Put device on failure

From: Michail Tatas

Date: Wed Aug 19 2026 - 06:57:22 EST


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@xxxxxxxxx>
---
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