net/tls: optimize judgement processes in tls_set_device_offload()

It is known that priority setting HW offload when set tls TX/RX offload
by setsockopt(). Check netdevice whether support NETIF_F_HW_TLS_TX or
not at the later stages in the whole tls_set_device_offload() process,
some memory allocations have been done before that. We must release those
memory and return error if we judge the netdevice not support
NETIF_F_HW_TLS_TX. It is redundant.

Move NETIF_F_HW_TLS_TX judgement forward, and move start_marker_record
and offload_ctx memory allocation back slightly. Thus, we can get
simpler exception handling process.

Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index b932469..12f7b56 100644 (file)
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -1028,20 +1028,21 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
        if (ctx->priv_ctx_tx)
                return -EEXIST;
 
-       start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
-       if (!start_marker_record)
-               return -ENOMEM;
+       netdev = get_netdev_for_sock(sk);
+       if (!netdev) {
+               pr_err_ratelimited("%s: netdev not found\n", __func__);
+               return -EINVAL;
+       }
 
-       offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
-       if (!offload_ctx) {
-               rc = -ENOMEM;
-               goto free_marker_record;
+       if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
+               rc = -EOPNOTSUPP;
+               goto release_netdev;
        }
 
        crypto_info = &ctx->crypto_send.info;
        if (crypto_info->version != TLS_1_2_VERSION) {
                rc = -EOPNOTSUPP;
-               goto free_offload_ctx;
+               goto release_netdev;
        }
 
        switch (crypto_info->cipher_type) {
@@ -1057,13 +1058,13 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
                break;
        default:
                rc = -EINVAL;
-               goto free_offload_ctx;
+               goto release_netdev;
        }
 
        /* Sanity-check the rec_seq_size for stack allocations */
        if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
                rc = -EINVAL;
-               goto free_offload_ctx;
+               goto release_netdev;
        }
 
        prot->version = crypto_info->version;
@@ -1077,7 +1078,7 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
                             GFP_KERNEL);
        if (!ctx->tx.iv) {
                rc = -ENOMEM;
-               goto free_offload_ctx;
+               goto release_netdev;
        }
 
        memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
@@ -1089,9 +1090,21 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
                goto free_iv;
        }
 
+       start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
+       if (!start_marker_record) {
+               rc = -ENOMEM;
+               goto free_rec_seq;
+       }
+
+       offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
+       if (!offload_ctx) {
+               rc = -ENOMEM;
+               goto free_marker_record;
+       }
+
        rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
        if (rc)
-               goto free_rec_seq;
+               goto free_offload_ctx;
 
        /* start at rec_seq - 1 to account for the start marker record */
        memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
@@ -1118,18 +1131,6 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
        if (skb)
                TCP_SKB_CB(skb)->eor = 1;
 
-       netdev = get_netdev_for_sock(sk);
-       if (!netdev) {
-               pr_err_ratelimited("%s: netdev not found\n", __func__);
-               rc = -EINVAL;
-               goto disable_cad;
-       }
-
-       if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
-               rc = -EOPNOTSUPP;
-               goto release_netdev;
-       }
-
        /* Avoid offloading if the device is down
         * We don't want to offload new flows after
         * the NETDEV_DOWN event
@@ -1167,20 +1168,19 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
 
 release_lock:
        up_read(&device_offload_lock);
-release_netdev:
-       dev_put(netdev);
-disable_cad:
        clean_acked_data_disable(inet_csk(sk));
        crypto_free_aead(offload_ctx->aead_send);
-free_rec_seq:
-       kfree(ctx->tx.rec_seq);
-free_iv:
-       kfree(ctx->tx.iv);
 free_offload_ctx:
        kfree(offload_ctx);
        ctx->priv_ctx_tx = NULL;
 free_marker_record:
        kfree(start_marker_record);
+free_rec_seq:
+       kfree(ctx->tx.rec_seq);
+free_iv:
+       kfree(ctx->tx.iv);
+release_netdev:
+       dev_put(netdev);
        return rc;
 }