From: Eric Dumazet edumazet@google.com
stable inclusion from linux-4.19.209 commit f6a6cced386920fe3d24b79ea129827766ae4106
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commit a9f5970767d11eadc805d5283f202612c7ba1f59 upstream.
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 Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Acked-by: Jason Yan yanaijie@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.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 8200a2f542b06..6ef22a9966246 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -932,7 +932,7 @@ 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; @@ -1240,7 +1240,7 @@ 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; @@ -2465,9 +2465,9 @@ 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); @@ -2580,7 +2580,7 @@ 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 b0553c0371e5a..581763d6df12d 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -1169,7 +1169,7 @@ 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 *);