[PATCH 22/33] ipv4: add ip_sock_set_recverr

Christoph Hellwig
2020-05-20T19:59:15Z

Add a helper to directly set the IP_RECVERR sockopt from kernel space
without going through a fake uaccess.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Howells <dhowells@redhat.com>
---
include/net/ip.h | 1 +
net/ipv4/ip_sockglue.c | 8 ++++++++
net/rxrpc/local_object.c | 8 +-------
3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/include/net/ip.h b/include/net/ip.h
index 5f5d8226b6abc..f063a491b9063 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -766,6 +766,7 @@ static inline bool inetdev_valid_mtu(unsigned int mtu)
}

void ip_sock_set_freebind(struct sock *sk);
+void ip_sock_set_recverr(struct sock *sk);
void ip_sock_set_tos(struct sock *sk, int val);

#endif /* _IP_H */
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 62e642ab80126..9a6a65b66f9d3 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -589,6 +589,14 @@ void ip_sock_set_freebind(struct sock *sk)
}
EXPORT_SYMBOL(ip_sock_set_freebind);

+void ip_sock_set_recverr(struct sock *sk)
+{
+ lock_sock(sk);
+ inet_sk(sk)->recverr = true;
+ release_sock(sk);
+}
+EXPORT_SYMBOL(ip_sock_set_recverr);
+
/*
* Socket option code for IP. This is the end of the line after any
* TCP,UDP etc options on an IP socket.
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index 5ea2bd01fdd59..4c0e8fe5ec1fb 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -171,13 +171,7 @@ static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
/* Fall through */
case AF_INET:
/* we want to receive ICMP errors */
- opt = 1;
- ret = kernel_setsockopt(local->socket, SOL_IP, IP_RECVERR,
- (char *) &opt, sizeof(opt));
- if (ret < 0) {
- _debug("setsockopt failed");
- goto error;
- }
+ ip_sock_set_recverr(local->socket->sk);

/* we want to set the don't fragment bit */
opt = IP_PMTUDISC_DO;
--
2.26.2