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 961b07d4d41ca7a677b1fd0d24f490888d784e0a..b61b893e9204f266ce200430f03bbb8d4497bf87 100644 (file)
--- 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: