From c1a7dedbcb0b60ecbcda0d2398ad5d2b078c9f47 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 14 Jul 2015 08:10:22 +0200 Subject: [PATCH] ipv6: lock socket in ip6_datagram_connect() [ Upstream commit 03645a11a570d52e70631838cb786eb4253eb463 ] ip6_datagram_connect() is doing a lot of socket changes without socket being locked. This looks wrong, at least for udp_lib_rehash() which could corrupt lists because of concurrent udp_sk(sk)->udp_portaddr_hash accesses. Signed-off-by: Eric Dumazet Acked-by: Herbert Xu Signed-off-by: David S. Miller [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- include/net/ip.h | 1 + net/ipv4/datagram.c | 16 ++++++++++++---- net/ipv6/datagram.c | 20 +++++++++++++++----- 3 files changed, 28 insertions(+), 9 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index 1ee535b7e187..2c7c5a9225df 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -138,6 +138,7 @@ static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) } /* datagram.c */ +int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); extern int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); diff --git a/net/ipv4/datagram.c b/net/ipv4/datagram.c index ec0751051db7..ffb8b6ee02a6 100644 --- a/net/ipv4/datagram.c +++ b/net/ipv4/datagram.c @@ -20,7 +20,7 @@ #include #include -int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) +int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct inet_sock *inet = inet_sk(sk); struct sockaddr_in *usin = (struct sockaddr_in *) uaddr; @@ -39,8 +39,6 @@ int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) sk_dst_reset(sk); - lock_sock(sk); - oif = sk->sk_bound_dev_if; saddr = inet->inet_saddr; if (ipv4_is_multicast(usin->sin_addr.s_addr)) { @@ -81,7 +79,17 @@ int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) sk_dst_set(sk, &rt->dst); err = 0; out: - release_sock(sk); return err; } +EXPORT_SYMBOL(__ip4_datagram_connect); + +int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) +{ + int res; + + lock_sock(sk); + res = __ip4_datagram_connect(sk, uaddr, addr_len); + release_sock(sk); + return res; +} EXPORT_SYMBOL(ip4_datagram_connect); diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c index 33719b7fa7d0..67f3632506ee 100644 --- a/net/ipv6/datagram.c +++ b/net/ipv6/datagram.c @@ -38,7 +38,7 @@ static inline int ipv6_mapped_addr_any(const struct in6_addr *a) return (ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0)); } -int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) +static int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; struct inet_sock *inet = inet_sk(sk); @@ -54,7 +54,7 @@ int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) if (usin->sin6_family == AF_INET) { if (__ipv6_only_sock(sk)) return -EAFNOSUPPORT; - err = ip4_datagram_connect(sk, uaddr, addr_len); + err = __ip4_datagram_connect(sk, uaddr, addr_len); goto ipv4_connected; } @@ -97,9 +97,9 @@ int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) sin.sin_addr.s_addr = daddr->s6_addr32[3]; sin.sin_port = usin->sin6_port; - err = ip4_datagram_connect(sk, - (struct sockaddr*) &sin, - sizeof(sin)); + err = __ip4_datagram_connect(sk, + (struct sockaddr *) &sin, + sizeof(sin)); ipv4_connected: if (err) @@ -203,6 +203,16 @@ out: return err; } +int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) +{ + int res; + + lock_sock(sk); + res = __ip6_datagram_connect(sk, uaddr, addr_len); + release_sock(sk); + return res; +} + void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, u32 info, u8 *payload) { -- 2.39.2