[net-next v2 1/5] net/tls: Do not enable zero-copy prematurely

[Vakul Garg]

Zero-copy mode was left enabled even when zerocopy_from_iter() failed.
Set the zero-copy mode only when zerocopy_from_iter() succeeds. This
leads to removal of argument 'zc' of function decrypt_skb_update().
Function decrypt_skb_update() does not need to check whether
ctx->decrypted is set since it is never called if ctx->decrypted is
true.

Signed-off-by: Vakul Garg <vakul.g...@nxp.com>
---
 net/tls/tls_sw.c | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 7d194c0cd6cf..e94cb54a6994 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -656,7 +656,7 @@ static struct sk_buff *tls_wait_data(struct sock *sk, int 
flags,
 }
 
 static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
-                             struct scatterlist *sgout, bool *zc)
+                             struct scatterlist *sgout)
 {
        struct tls_context *tls_ctx = tls_get_ctx(sk);
        struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
@@ -668,13 +668,9 @@ static int decrypt_skb_update(struct sock *sk, struct 
sk_buff *skb,
        if (err < 0)
                return err;
 #endif
-       if (!ctx->decrypted) {
-               err = decrypt_skb(sk, skb, sgout);
-               if (err < 0)
-                       return err;
-       } else {
-               *zc = false;
-       }
+       err = decrypt_skb(sk, skb, sgout);
+       if (err < 0)
+               return err;
 
        rxm->offset += tls_ctx->rx.prepend_size;
        rxm->full_len -= tls_ctx->rx.overhead_size;
@@ -819,7 +815,6 @@ int tls_sw_recvmsg(struct sock *sk,
                                struct scatterlist sgin[MAX_SKB_FRAGS + 1];
                                int pages = 0;
 
-                               zc = true;
                                sg_init_table(sgin, MAX_SKB_FRAGS + 1);
                                sg_set_buf(&sgin[0], ctx->rx_aad_plaintext,
                                           TLS_AAD_SPACE_SIZE);
@@ -830,8 +825,10 @@ int tls_sw_recvmsg(struct sock *sk,
                                                         MAX_SKB_FRAGS, false, 
true);
                                if (err < 0)
                                        goto fallback_to_reg_recv;
+                               else
+                                       zc = true;
 
-                               err = decrypt_skb_update(sk, skb, sgin, &zc);
+                               err = decrypt_skb_update(sk, skb, sgin);
                                for (; pages > 0; pages--)
                                        put_page(sg_page(&sgin[pages]));
                                if (err < 0) {
@@ -840,7 +837,7 @@ int tls_sw_recvmsg(struct sock *sk,
                                }
                        } else {
 fallback_to_reg_recv:
-                               err = decrypt_skb_update(sk, skb, NULL, &zc);
+                               err = decrypt_skb_update(sk, skb, NULL);
                                if (err < 0) {
                                        tls_err_abort(sk, EBADMSG);
                                        goto recv_end;
@@ -895,7 +892,6 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t 
*ppos,
        int err = 0;
        long timeo;
        int chunk;
-       bool zc;
 
        lock_sock(sk);
 
@@ -912,7 +908,7 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t 
*ppos,
        }
 
        if (!ctx->decrypted) {
-               err = decrypt_skb_update(sk, skb, NULL, &zc);
+               err = decrypt_skb_update(sk, skb, NULL);
 
                if (err < 0) {
                        tls_err_abort(sk, EBADMSG);
-- 
2.13.6