net/tls: don't leak IV and record seq when offload fails

When device refuses the offload in tls_set_device_offload_rx()
it calls tls_sw_free_resources_rx() to clean up software context
state.

Unfortunately, tls_sw_free_resources_rx() does not free all
the state tls_set_sw_offload() allocated - it leaks IV and
sequence number buffers.  All other code paths which lead to
tls_sw_release_resources_rx() (which tls_sw_free_resources_rx()
calls) free those right before the call.

Avoid the leak by moving freeing of iv and rec_seq into
tls_sw_release_resources_rx().

Fixes: 4799ac81 ("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>

net/tls/tls_device.c

@@ -941,8 +941,6 @@ void tls_device_offload_cleanup_rx(struct sock *sk)
 	}
 out:
 	up_read(&device_offload_lock);
-	kfree(tls_ctx->rx.rec_seq);
-	kfree(tls_ctx->rx.iv);
 	tls_sw_release_resources_rx(sk);
 }
 

net/tls/tls_main.c

@@ -293,11 +293,8 @@ static void tls_sk_proto_close(struct sock *sk, long timeout)
 #endif
 	}
 
-	if (ctx->rx_conf == TLS_SW) {
-		kfree(ctx->rx.rec_seq);
-		kfree(ctx->rx.iv);
+	if (ctx->rx_conf == TLS_SW)
 		tls_sw_free_resources_rx(sk);
-	}
 
 #ifdef CONFIG_TLS_DEVICE
 	if (ctx->rx_conf == TLS_HW)

net/tls/tls_sw.c

@@ -2078,6 +2078,9 @@ void tls_sw_release_resources_rx(struct sock *sk)
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
 	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
 
+	kfree(tls_ctx->rx.rec_seq);
+	kfree(tls_ctx->rx.iv);
+
 	if (ctx->aead_recv) {
 		kfree_skb(ctx->recv_pkt);
 		ctx->recv_pkt = NULL;