From: Cong Wang <cong.w...@bytedance.com>
Similarly, udpv6_sendmsg() takes lock_sock() inside too,
we have to build ->sendmsg_locked() on top of it.
For ->read_sock(), we can just use udp_read_sock().
Cc: John Fastabend <john.fastab...@gmail.com>
Cc: Daniel Borkmann <dan...@iogearbox.net>
Cc: Jakub Sitnicki <ja...@cloudflare.com>
Cc: Lorenz Bauer <l...@cloudflare.com>
Signed-off-by: Cong Wang <cong.w...@bytedance.com>
---
include/net/ipv6.h | 1 +
net/ipv4/udp.c | 1 +
net/ipv6/af_inet6.c | 2 ++
net/ipv6/udp.c | 27 +++++++++++++++++++++------
4 files changed, 25 insertions(+), 6 deletions(-)
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index bd1f396cc9c7..48b6850dae85 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -1119,6 +1119,7 @@ int inet6_hash_connect(struct inet_timewait_death_row
*death_row,
int inet6_sendmsg(struct socket *sock, struct msghdr *msg, size_t size);
int inet6_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
int flags);
+int udpv6_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
/*
* reassembly.c
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index fd8f27ee5b4e..6658db231475 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1831,6 +1831,7 @@ int udp_read_sock(struct sock *sk, read_descriptor_t
*desc,
return copied;
}
+EXPORT_SYMBOL(udp_read_sock);
/*
* This should be easy, if there is something there we
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 1fb75f01756c..634ab3a825d7 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -714,7 +714,9 @@ const struct proto_ops inet6_dgram_ops = {
.setsockopt = sock_common_setsockopt, /* ok */
.getsockopt = sock_common_getsockopt, /* ok */
.sendmsg = inet6_sendmsg, /* retpoline's sake */
+ .sendmsg_locked = udpv6_sendmsg_locked,
.recvmsg = inet6_recvmsg, /* retpoline's sake */
+ .read_sock = udp_read_sock,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
.set_peek_off = sk_set_peek_off,
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index ef2c75bb4771..124a316da410 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1272,7 +1272,7 @@ static int udp_v6_push_pending_frames(struct sock *sk)
return err;
}
-int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
+static int __udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len,
bool locked)
{
struct ipv6_txoptions opt_space;
struct udp_sock *up = udp_sk(sk);
@@ -1361,7 +1361,8 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg,
size_t len)
* There are pending frames.
* The socket lock must be held while it's corked.
*/
- lock_sock(sk);
+ if (!locked)
+ lock_sock(sk);
if (likely(up->pending)) {
if (unlikely(up->pending != AF_INET6)) {
release_sock(sk);
@@ -1370,7 +1371,8 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg,
size_t len)
dst = NULL;
goto do_append_data;
}
- release_sock(sk);
+ if (!locked)
+ release_sock(sk);
}
ulen += sizeof(struct udphdr);
@@ -1533,11 +1535,13 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg,
size_t len)
goto out;
}
- lock_sock(sk);
+ if (!locked)
+ lock_sock(sk);
if (unlikely(up->pending)) {
/* The socket is already corked while preparing it. */
/* ... which is an evident application bug. --ANK */
- release_sock(sk);
+ if (!locked)
+ release_sock(sk);
net_dbg_ratelimited("udp cork app bug 2\n");
err = -EINVAL;
@@ -1562,7 +1566,8 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg,
size_t len)
if (err > 0)
err = np->recverr ? net_xmit_errno(err) : 0;
- release_sock(sk);
+ if (!locked)
+ release_sock(sk);
out:
dst_release(dst);
@@ -1593,6 +1598,16 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg,
size_t len)
goto out;
}
+int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
+{
+ return __udpv6_sendmsg(sk, msg, len, false);
+}
+
+int udpv6_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len)
+{
+ return __udpv6_sendmsg(sk, msg, len, true);
+}
+
void udpv6_destroy_sock(struct sock *sk)
{
struct udp_sock *up = udp_sk(sk);
--
2.25.1
