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:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Laurent Vivier <lvivier@redhat.com>,
        "Michael S . Tsirkin" <mst@redhat.com>,
        Sasha Levin <sashal@kernel.org>, kvm@vger.kernel.org,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org
Subject: [PATCH AUTOSEL 5.11 23/44] vhost: Fix vhost_vq_reset()
Date:   Thu, 25 Mar 2021 07:24:38 -0400
Message-Id: <20210325112459.1926846-23-sashal@kernel.org>
In-Reply-To: <20210325112459.1926846-1-sashal@kernel.org>
References: <20210325112459.1926846-1-sashal@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Laurent Vivier <lvivier@redhat.com>

[ Upstream commit beb691e69f4dec7bfe8b81b509848acfd1f0dbf9 ]

vhost_reset_is_le() is vhost_init_is_le(), and in the case of
cross-endian legacy, vhost_init_is_le() depends on vq->user_be.

vq->user_be is set by vhost_disable_cross_endian().

But in vhost_vq_reset(), we have:

    vhost_reset_is_le(vq);
    vhost_disable_cross_endian(vq);

And so user_be is used before being set.

To fix that, reverse the lines order as there is no other dependency
between them.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Link: https://lore.kernel.org/r/20210312140913.788592-1-lvivier@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/vhost/vhost.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index a262e12c6dc2..5ccb0705beae 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -332,8 +332,8 @@ static void vhost_vq_reset(struct vhost_dev *dev,
 	vq->error_ctx = NULL;
 	vq->kick = NULL;
 	vq->log_ctx = NULL;
-	vhost_reset_is_le(vq);
 	vhost_disable_cross_endian(vq);
+	vhost_reset_is_le(vq);
 	vq->busyloop_timeout = 0;
 	vq->umem = NULL;
 	vq->iotlb = NULL;
-- 
2.30.1