If a protocol doesn't support zerocopy it will silently fall back to
copying. This type of behaviour has always been a source of troubles
so it's better to fail such requests instead. For now explicitly
whitelist supported protocols in io_uring, which should be turned later
into a socket flag.
Cc: <stable@xxxxxxxxxxxxxxx> # 6.0
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
io_uring/net.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/io_uring/net.c b/io_uring/net.c
index 8c7226b5bf41..28127f1de1f0 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -120,6 +120,13 @@ static void io_netmsg_recycle(struct io_kiocb *req, unsigned int issue_flags)
}
}
+static inline bool io_sock_support_zc(struct socket *sock)
+{
+ return likely(sock->sk && sk_fullsock(sock->sk) &&
+ (sock->sk->sk_protocol == IPPROTO_TCP ||
+ sock->sk->sk_protocol == IPPROTO_UDP));
+}
+
static struct io_async_msghdr *io_msg_alloc_async(struct io_kiocb *req,
unsigned int issue_flags)
{
@@ -1056,6 +1063,8 @@ int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
sock = sock_from_file(req->file);
if (unlikely(!sock))
return -ENOTSOCK;
+ if (!io_sock_support_zc(sock))
+ return -EOPNOTSUPP;
msg.msg_name = NULL;
msg.msg_control = NULL;
--
2.38.0
