net/tls: avoid spurious decryption error with HW resync

When device loses sync mid way through a record - kernel
has to re-encrypt the part of the record which the device
already decrypted to be able to decrypt and authenticate
the record in its entirety.

The re-encryption piggy backs on the decryption routine,
but obviously because the partially decrypted record can't
be authenticated crypto API returns an error which is then
ignored by tls_device_reencrypt().

Commit 5c5ec66858 ("net/tls: add TlsDecryptError stat")
added a statistic to count decryption errors, this statistic
can't be incremented when we see the expected re-encryption
error. Move the inc to the caller.

Reported-and-tested-by: David Beckett <david.beckett@netronome.com>
Fixes: 5c5ec66858 ("net/tls: add TlsDecryptError stat")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jakub Kicinski 2020-01-10 04:36:55 -08:00 committed by David S. Miller
parent e267371dd3
commit 5c5d22a750

View file

@ -256,8 +256,6 @@ static int tls_do_decryption(struct sock *sk,
return ret;
ret = crypto_wait_req(ret, &ctx->async_wait);
} else if (ret == -EBADMSG) {
TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
}
if (async)
@ -1515,7 +1513,9 @@ static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
if (err == -EINPROGRESS)
tls_advance_record_sn(sk, prot,
&tls_ctx->rx);
else if (err == -EBADMSG)
TLS_INC_STATS(sock_net(sk),
LINUX_MIB_TLSDECRYPTERROR);
return err;
}
} else {