tls: don't use stack memory in a scatterlist

scatterlist code expects virt_to_page() to work, which fails with
CONFIG_VMAP_STACK=y.

Fixes: c46234ebb4d1e ("tls: RX path for ktls")
Signed-off-by: Matt Mullins <mmullins@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tls.h b/include/net/tls.h
index b400d0b..f5fb16d 100644 (file)
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -97,6 +97,9 @@ struct tls_sw_context {
        u8 control;
        bool decrypted;
 
+       char rx_aad_ciphertext[TLS_AAD_SPACE_SIZE];
+       char rx_aad_plaintext[TLS_AAD_SPACE_SIZE];
+
        /* Sending context */
        char aad_space[TLS_AAD_SPACE_SIZE];
 

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 71e7959..e1c93ce 100644 (file)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -680,7 +680,6 @@ static int decrypt_skb(struct sock *sk, struct sk_buff *skb,
        struct scatterlist *sgin = &sgin_arr[0];
        struct strp_msg *rxm = strp_msg(skb);
        int ret, nsg = ARRAY_SIZE(sgin_arr);
-       char aad_recv[TLS_AAD_SPACE_SIZE];
        struct sk_buff *unused;
 
        ret = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
@@ -698,13 +697,13 @@ static int decrypt_skb(struct sock *sk, struct sk_buff *skb,
        }
 
        sg_init_table(sgin, nsg);
-       sg_set_buf(&sgin[0], aad_recv, sizeof(aad_recv));
+       sg_set_buf(&sgin[0], ctx->rx_aad_ciphertext, TLS_AAD_SPACE_SIZE);
 
        nsg = skb_to_sgvec(skb, &sgin[1],
                           rxm->offset + tls_ctx->rx.prepend_size,
                           rxm->full_len - tls_ctx->rx.prepend_size);
 
-       tls_make_aad(aad_recv,
+       tls_make_aad(ctx->rx_aad_ciphertext,
                     rxm->full_len - tls_ctx->rx.overhead_size,
                     tls_ctx->rx.rec_seq,
                     tls_ctx->rx.rec_seq_size,
@@ -803,12 +802,12 @@ int tls_sw_recvmsg(struct sock *sk,
                        if (to_copy <= len && page_count < MAX_SKB_FRAGS &&
                            likely(!(flags & MSG_PEEK)))  {
                                struct scatterlist sgin[MAX_SKB_FRAGS + 1];
-                               char unused[21];
                                int pages = 0;
 
                                zc = true;
                                sg_init_table(sgin, MAX_SKB_FRAGS + 1);
-                               sg_set_buf(&sgin[0], unused, 13);
+                               sg_set_buf(&sgin[0], ctx->rx_aad_plaintext,
+                                          TLS_AAD_SPACE_SIZE);
 
                                err = zerocopy_from_iter(sk, &msg->msg_iter,
                                                         to_copy, &pages,