linux-kernel - [PATCH AUTOSEL 4.14 190/371] vfio/mdev: Avoid release parent reference during error path

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200116172403.18149-133-sashal@kernel.org>
Date:   Thu, 16 Jan 2020 12:21:02 -0500
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Parav Pandit <parav@...lanox.com>,
        Cornelia Huck <cohuck@...hat.com>,
        Kirti Wankhede <kwankhede@...dia.com>,
        Maxim Levitsky <mlevitsk@...hat.com>,
        Alex Williamson <alex.williamson@...hat.com>,
        Sasha Levin <sashal@...nel.org>, kvm@...r.kernel.org
Subject: [PATCH AUTOSEL 4.14 190/371] vfio/mdev: Avoid release parent reference during error path

From: Parav Pandit <parav@...lanox.com>

[ Upstream commit 60e7f2c3fe9919cee9534b422865eed49f4efb15 ]

During mdev parent registration in mdev_register_device(),
if parent device is duplicate, it releases the reference of existing
parent device.
This is incorrect. Existing parent device should not be touched.

Fixes: 7b96953bc640 ("vfio: Mediated device Core driver")
Reviewed-by: Cornelia Huck <cohuck@...hat.com>
Reviewed-by: Kirti Wankhede <kwankhede@...dia.com>
Reviewed-by: Maxim Levitsky <mlevitsk@...hat.com>
Signed-off-by: Parav Pandit <parav@...lanox.com>
Signed-off-by: Alex Williamson <alex.williamson@...hat.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/vfio/mdev/mdev_core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 0212f0ee8aea..8cfa71230877 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -182,6 +182,7 @@ int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops)
 	/* Check for duplicate */
 	parent = __find_parent_device(dev);
 	if (parent) {
+		parent = NULL;
 		ret = -EEXIST;
 		goto add_dev_err;
 	}
-- 
2.20.1