Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Dan Carpenter <dan.carpenter@oracle.com>,
        Andrea Parri <parri.andrea@gmail.com>,
        Wei Liu <wei.liu@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.12 320/677] Drivers: hv: vmbus: Use after free in __vmbus_open()
Date:   Wed, 12 May 2021 16:46:06 +0200
Message-Id: <20210512144847.860102293@linuxfoundation.org>
In-Reply-To: <20210512144837.204217980@linuxfoundation.org>
References: <20210512144837.204217980@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 3e9bf43f7f7a46f21ec071cb47be92d0874c48da ]

The "open_info" variable is added to the &vmbus_connection.chn_msg_list,
but the error handling frees "open_info" without removing it from the
list.  This will result in a use after free.  First remove it from the
list, and then free it.

Fixes: 6f3d791f3006 ("Drivers: hv: vmbus: Fix rescind handling issues")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
Link: https://lore.kernel.org/r/YHV3XLCot6xBS44r@mwanda
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hv/channel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 0bd202de7960..945e41f5e3a8 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -653,7 +653,7 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
 
 	if (newchannel->rescind) {
 		err = -ENODEV;
-		goto error_free_info;
+		goto error_clean_msglist;
 	}
 
 	err = vmbus_post_msg(open_msg,
-- 
2.30.2