Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Jakub Kicinski <jakub.kicinski@netronome.com>,
        Dirk van der Merwe <dirk.vandermerwe@netronome.com>,
        "David S. Miller" <davem@davemloft.net>
Subject: [PATCH 5.0 88/89] net/tls: avoid potential deadlock in tls_set_device_offload_rx()
Date:   Tue, 30 Apr 2019 13:39:19 +0200
Message-Id: <20190430113613.930256964@linuxfoundation.org>
In-Reply-To: <20190430113609.741196396@linuxfoundation.org>
References: <20190430113609.741196396@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Jakub Kicinski <jakub.kicinski@netronome.com>

[ Upstream commit 62ef81d5632634d5e310ed25b9b940b2b6612b46 ]

If device supports offload, but offload fails tls_set_device_offload_rx()
will call tls_sw_free_resources_rx() which (unhelpfully) releases
and reacquires the socket lock.

For a small fix release and reacquire the device_offload_lock.

Fixes: 4799ac81e52a ("tls: Add rx inline crypto offload")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/tls/tls_device.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -884,7 +884,9 @@ int tls_set_device_offload_rx(struct soc
 	goto release_netdev;
 
 free_sw_resources:
+	up_read(&device_offload_lock);
 	tls_sw_free_resources_rx(sk);
+	down_read(&device_offload_lock);
 release_ctx:
 	ctx->priv_ctx_rx = NULL;
 release_netdev: