[SRU][F][PATCH 2/2] uio_hv_generic: Fix another memory leak in error handling paths

[Bethany Jamison]

From: Christophe JAILLET <christophe.jaillet at wanadoo.fr>

Memory allocated by 'vmbus_alloc_ring()' at the beginning of the probe
function is never freed in the error handling path.

Add the missing 'vmbus_free_ring()' call.

Note that it is already freed in the .remove function.

Fixes: cdfa835c6e5e ("uio_hv_generic: defer opening vmbus until first use")
Cc: stable <stable at vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet at wanadoo.fr>
Link: https://lore.kernel.org/r/0d86027b8eeed8e6360bc3d52bcdb328ff9bdca1.1620544055.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
(cherry picked from commit 0b0226be3a52dadd965644bc52a807961c2c26df)
CVE-2021-47070
Signed-off-by: Bethany Jamison <bethany.jamison at canonical.com>
---
 drivers/uio/uio_hv_generic.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c
index 47387e6f745cf..d533eb09d74a5 100644
--- a/drivers/uio/uio_hv_generic.c
+++ b/drivers/uio/uio_hv_generic.c
@@ -291,7 +291,7 @@ hv_uio_probe(struct hv_device *dev,
 	pdata->recv_buf = vzalloc(RECV_BUFFER_SIZE);
 	if (pdata->recv_buf == NULL) {
 		ret = -ENOMEM;
-		goto fail_close;
+		goto fail_free_ring;
 	}
 
 	ret = vmbus_establish_gpadl(channel, pdata->recv_buf,
@@ -351,6 +351,8 @@ hv_uio_probe(struct hv_device *dev,
 
 fail_close:
 	hv_uio_cleanup(dev, pdata);
+fail_free_ring:
+	vmbus_free_ring(dev->channel);
 
 	return ret;
 }
-- 
2.34.1