From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Fri, 19 Apr 2019 23:51:38 +0000 (-0700)
Subject: net/tls: avoid potential deadlock in tls_set_device_offload_rx()
X-Git-Tag: v4.19.38~3
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d3bdd359fa53c1d577bc96677474c43bfb9090bd;p=thirdparty%2Fkernel%2Fstable.git

net/tls: avoid potential deadlock in tls_set_device_offload_rx()

[ 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>
---

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 961b07d4d41ca..b61b893e9204f 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -874,7 +874,9 @@ int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
 	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: