From: Eric Dumazet <eric.dumazet@gmail.com>
To: "David S . Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>
Cc: netdev <netdev@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
Eric Dumazet <eric.dumazet@gmail.com>
Subject: [PATCH net] net: udp: annotate data race around udp_sk(sk)->corkflag
Date: Mon, 27 Sep 2021 17:29:24 -0700 [thread overview]
Message-ID: <20210928002924.629469-1-eric.dumazet@gmail.com> (raw)
From: Eric Dumazet <edumazet@google.com>
up->corkflag field can be read or written without any lock.
Annotate accesses to avoid possible syzbot/KCSAN reports.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
---
net/ipv4/udp.c | 10 +++++-----
net/ipv6/udp.c | 2 +-
2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 8851c9463b4b62c9017565f545250c4ffe22927c..2a7825a5b84254b70b2f06fc04d601719c2e0bc3 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1053,7 +1053,7 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
__be16 dport;
u8 tos;
int err, is_udplite = IS_UDPLITE(sk);
- int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
+ int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
struct sk_buff *skb;
struct ip_options_data opt_copy;
@@ -1361,7 +1361,7 @@ int udp_sendpage(struct sock *sk, struct page *page, int offset,
}
up->len += size;
- if (!(up->corkflag || (flags&MSG_MORE)))
+ if (!(READ_ONCE(up->corkflag) || (flags&MSG_MORE)))
ret = udp_push_pending_frames(sk);
if (!ret)
ret = size;
@@ -2662,9 +2662,9 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname,
switch (optname) {
case UDP_CORK:
if (val != 0) {
- up->corkflag = 1;
+ WRITE_ONCE(up->corkflag, 1);
} else {
- up->corkflag = 0;
+ WRITE_ONCE(up->corkflag, 0);
lock_sock(sk);
push_pending_frames(sk);
release_sock(sk);
@@ -2787,7 +2787,7 @@ int udp_lib_getsockopt(struct sock *sk, int level, int optname,
switch (optname) {
case UDP_CORK:
- val = up->corkflag;
+ val = READ_ONCE(up->corkflag);
break;
case UDP_ENCAP:
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index ea53847b5b7e8b82f1898fa442327a9ce060085f..e505bb007e9f97995bf64a37702e0dc44a8c4a5c 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1303,7 +1303,7 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
int addr_len = msg->msg_namelen;
bool connected = false;
int ulen = len;
- int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
+ int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
int err;
int is_udplite = IS_UDPLITE(sk);
int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
--
2.33.0.685.g46640cef36-goog
next reply other threads:[~2021-09-28 0:29 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-28 0:29 Eric Dumazet [this message]
2021-09-28 12:30 ` [PATCH net] net: udp: annotate data race around udp_sk(sk)->corkflag patchwork-bot+netdevbpf
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