From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Fri, 19 Apr 2019 16:51:38 -0700
Subject: net/tls: avoid potential deadlock in tls_set_device_offload_rx()
Patch-mainline: v5.1-rc7
Git-commit: 62ef81d5632634d5e310ed25b9b940b2b6612b46
References: bsc#1109837

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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/tls/tls_device.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -899,7 +899,9 @@ 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: