[PATCH net-next v5 06/14] tls/device: Use splice_eof() to flush

David Howells
2023-06-07T14:32:04Z

Allow splice to end a TLS record after prematurely ending a splice/sendfile
due to getting an EOF condition (->splice_read() returned 0) after splice
had called TLS with a sendmsg() with MSG_MORE set when the user didn't set
MSG_MORE.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=wh=V579PDYvkpnTobCLGczbgxpMgGmmhqiTyE34Cpi5Gg@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Boris Pismenny <borisp@nvidia.com>
cc: John Fastabend <john.fastabend@gmail.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Eric Dumazet <edumazet@google.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: netdev@vger.kernel.org
---
net/tls/tls.h | 1 +
net/tls/tls_device.c | 23 +++++++++++++++++++++++
net/tls/tls_main.c | 2 ++
3 files changed, 26 insertions(+)

diff --git a/net/tls/tls.h b/net/tls/tls.h
index 4922668fefaa..d002c3af1966 100644
--- a/net/tls/tls.h
+++ b/net/tls/tls.h
@@ -116,6 +116,7 @@ ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
size_t len, unsigned int flags);

int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
+void tls_device_splice_eof(struct socket *sock);
int tls_device_sendpage(struct sock *sk, struct page *page,
int offset, size_t size, int flags);
int tls_tx_records(struct sock *sk, int flags);
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 9ef766e41c7a..439be833dcf9 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -590,6 +590,29 @@ int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
return rc;
}

+void tls_device_splice_eof(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct tls_context *tls_ctx = tls_get_ctx(sk);
+ union tls_iter_offset iter;
+ struct iov_iter iov_iter = {};
+
+ if (!tls_is_partially_sent_record(tls_ctx))
+ return;
+
+ mutex_lock(&tls_ctx->tx_lock);
+ lock_sock(sk);
+
+ if (tls_is_partially_sent_record(tls_ctx)) {
+ iov_iter_bvec(&iov_iter, ITER_SOURCE, NULL, 0, 0);
+ iter.msg_iter = &iov_iter;
+ tls_push_data(sk, iter, 0, 0, TLS_RECORD_TYPE_DATA, NULL);
+ }
+
+ release_sock(sk);
+ mutex_unlock(&tls_ctx->tx_lock);
+}
+
int tls_device_sendpage(struct sock *sk, struct page *page,
int offset, size_t size, int flags)
{
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index 82ec5c654f32..7b9c83dd7de2 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -1044,10 +1044,12 @@ static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
#ifdef CONFIG_TLS_DEVICE
prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
prot[TLS_HW][TLS_BASE].sendmsg = tls_device_sendmsg;
+ prot[TLS_HW][TLS_BASE].splice_eof = tls_device_splice_eof;
prot[TLS_HW][TLS_BASE].sendpage = tls_device_sendpage;

prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
prot[TLS_HW][TLS_SW].sendmsg = tls_device_sendmsg;
+ prot[TLS_HW][TLS_SW].splice_eof = tls_device_splice_eof;
prot[TLS_HW][TLS_SW].sendpage = tls_device_sendpage;

prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];