net/tls: check return values from skb_copy_bits() and skb_store_bits()

In light of recent bugs, we should make a better effort of
checking return values.  In theory none of the functions should
fail today.

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>

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index b95c408..dde6513 100644 (file)
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -603,8 +603,10 @@ static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
        sg_set_buf(&sg[0], buf,
                   rxm->full_len + TLS_HEADER_SIZE +
                   TLS_CIPHER_AES_GCM_128_IV_SIZE);
-       skb_copy_bits(skb, offset, buf,
-                     TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
+       err = skb_copy_bits(skb, offset, buf,
+                           TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
+       if (err)
+               goto free_buf;
 
        /* We are interested only in the decrypted data not the auth */
        err = decrypt_skb(sk, skb, sg);
@@ -618,8 +620,11 @@ static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
        if (skb_pagelen(skb) > offset) {
                copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 
-               if (skb->decrypted)
-                       skb_store_bits(skb, offset, buf, copy);
+               if (skb->decrypted) {
+                       err = skb_store_bits(skb, offset, buf, copy);
+                       if (err)
+                               goto free_buf;
+               }
 
                offset += copy;
                buf += copy;
@@ -642,8 +647,11 @@ static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
                copy = min_t(int, skb_iter->len - frag_pos,
                             data_len + rxm->offset - offset);
 
-               if (skb_iter->decrypted)
-                       skb_store_bits(skb_iter, frag_pos, buf, copy);
+               if (skb_iter->decrypted) {
+                       err = skb_store_bits(skb_iter, frag_pos, buf, copy);
+                       if (err)
+                               goto free_buf;
+               }
 
                offset += copy;
                buf += copy;