tls: fix skb_to_sgvec returning unhandled error.

The current code does not inspect the return value of skb_to_sgvec. This
can cause a nullptr kernel panic when the malformed sgvec is passed into
the crypto request.

Checking the return value of skb_to_sgvec and skipping decryption if it
is negative fixes this problem.

Fixes: c46234ebb4 ("tls: RX path for ktls")
Acked-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Doron Roberts-Kedes 2018-07-02 10:25:05 -07:00 committed by David S. Miller
parent c643ecf354
commit 52ee6ef36e

View File

@ -701,6 +701,10 @@ static int decrypt_skb(struct sock *sk, struct sk_buff *skb,
nsg = skb_to_sgvec(skb, &sgin[1],
rxm->offset + tls_ctx->rx.prepend_size,
rxm->full_len - tls_ctx->rx.prepend_size);
if (nsg < 0) {
ret = nsg;
goto out;
}
tls_make_aad(ctx->rx_aad_ciphertext,
rxm->full_len - tls_ctx->rx.overhead_size,
@ -712,6 +716,7 @@ static int decrypt_skb(struct sock *sk, struct sk_buff *skb,
rxm->full_len - tls_ctx->rx.overhead_size,
skb, sk->sk_allocation);
out:
if (sgin != &sgin_arr[0])
kfree(sgin);