patch "uio_hv_generic: Fix a memory leak in error handling paths" added to char-misc-linus

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    uio_hv_generic: Fix a memory leak in error handling paths

to my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


From 3ee098f96b8b6c1a98f7f97915f8873164e6af9d Mon Sep 17 00:00:00 2001
From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Sun, 9 May 2021 09:13:03 +0200
Subject: uio_hv_generic: Fix a memory leak in error handling paths

If 'vmbus_establish_gpadl()' fails, the (recv|send)_gpadl will not be
updated and 'hv_uio_cleanup()' in the error handling path will not be
able to free the corresponding buffer.

In such a case, we need to free the buffer explicitly.

Fixes: cdfa835c6e5e ("uio_hv_generic: defer opening vmbus until first use")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/4fdaff557deef6f0475d02ba7922ddbaa1ab08a6.1620544055.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/uio/uio_hv_generic.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/uio/uio_hv_generic.c b/drivers/uio/uio_hv_generic.c
index 0330ba99730e..eebc399f2cc7 100644
--- a/drivers/uio/uio_hv_generic.c
+++ b/drivers/uio/uio_hv_generic.c
@@ -296,8 +296,10 @@ hv_uio_probe(struct hv_device *dev,
 
 	ret = vmbus_establish_gpadl(channel, pdata->recv_buf,
 				    RECV_BUFFER_SIZE, &pdata->recv_gpadl);
-	if (ret)
+	if (ret) {
+		vfree(pdata->recv_buf);
 		goto fail_close;
+	}
 
 	/* put Global Physical Address Label in name */
 	snprintf(pdata->recv_name, sizeof(pdata->recv_name),
@@ -316,8 +318,10 @@ hv_uio_probe(struct hv_device *dev,
 
 	ret = vmbus_establish_gpadl(channel, pdata->send_buf,
 				    SEND_BUFFER_SIZE, &pdata->send_gpadl);
-	if (ret)
+	if (ret) {
+		vfree(pdata->send_buf);
 		goto fail_close;
+	}
 
 	snprintf(pdata->send_name, sizeof(pdata->send_name),
 		 "send:%u", pdata->send_gpadl);
-- 
2.31.1