From c889a99a21bf124c3db08d09df919f0eccc5ea4c Mon Sep 17 00:00:00 2001 From: Jordan Rife Date: Thu, 21 Sep 2023 18:46:42 -0500 Subject: [PATCH] net: prevent address rewrite in kernel_bind() Similar to the change in commit 0bdf399342c5("net: Avoid address overwrite in kernel_connect"), BPF hooks run on bind may rewrite the address passed to kernel_bind(). This change 1) Makes a copy of the bind address in kernel_bind() to insulate callers. 2) Replaces direct calls to sock->ops->bind() in net with kernel_bind() Link: https://lore.kernel.org/netdev/20230912013332.2048422-1-jrife@google.com/ Fixes: 4fbac77d2d09 ("bpf: Hooks for sys_bind") Cc: stable@vger.kernel.org Reviewed-by: Willem de Bruijn Signed-off-by: Jordan Rife Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- net/netfilter/ipvs/ip_vs_sync.c | 4 ++-- net/rds/tcp_connect.c | 2 +- net/rds/tcp_listen.c | 2 +- net/socket.c | 7 ++++++- 4 files changed, 10 insertions(+), 5 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c index 6e4ed1e11a3b..4174076c66fa 100644 --- a/net/netfilter/ipvs/ip_vs_sync.c +++ b/net/netfilter/ipvs/ip_vs_sync.c @@ -1439,7 +1439,7 @@ static int bind_mcastif_addr(struct socket *sock, struct net_device *dev) sin.sin_addr.s_addr = addr; sin.sin_port = 0; - return sock->ops->bind(sock, (struct sockaddr*)&sin, sizeof(sin)); + return kernel_bind(sock, (struct sockaddr *)&sin, sizeof(sin)); } static void get_mcast_sockaddr(union ipvs_sockaddr *sa, int *salen, @@ -1546,7 +1546,7 @@ static int make_receive_sock(struct netns_ipvs *ipvs, int id, get_mcast_sockaddr(&mcast_addr, &salen, &ipvs->bcfg, id); sock->sk->sk_bound_dev_if = dev->ifindex; - result = sock->ops->bind(sock, (struct sockaddr *)&mcast_addr, salen); + result = kernel_bind(sock, (struct sockaddr *)&mcast_addr, salen); if (result < 0) { pr_err("Error binding to the multicast addr\n"); goto error; diff --git a/net/rds/tcp_connect.c b/net/rds/tcp_connect.c index d788c6d28986..a0046e99d6df 100644 --- a/net/rds/tcp_connect.c +++ b/net/rds/tcp_connect.c @@ -145,7 +145,7 @@ int rds_tcp_conn_path_connect(struct rds_conn_path *cp) addrlen = sizeof(sin); } - ret = sock->ops->bind(sock, addr, addrlen); + ret = kernel_bind(sock, addr, addrlen); if (ret) { rdsdebug("bind failed with %d at address %pI6c\n", ret, &conn->c_laddr); diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index 014fa24418c1..53b3535a1e4a 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -306,7 +306,7 @@ struct socket *rds_tcp_listen_init(struct net *net, bool isv6) addr_len = sizeof(*sin); } - ret = sock->ops->bind(sock, (struct sockaddr *)&ss, addr_len); + ret = kernel_bind(sock, (struct sockaddr *)&ss, addr_len); if (ret < 0) { rdsdebug("could not bind %s listener socket: %d\n", isv6 ? "IPv6" : "IPv4", ret); diff --git a/net/socket.c b/net/socket.c index a39ec136f5cf..c4a6f5532955 100644 --- a/net/socket.c +++ b/net/socket.c @@ -3516,7 +3516,12 @@ static long compat_sock_ioctl(struct file *file, unsigned int cmd, int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen) { - return READ_ONCE(sock->ops)->bind(sock, addr, addrlen); + struct sockaddr_storage address; + + memcpy(&address, addr, addrlen); + + return READ_ONCE(sock->ops)->bind(sock, (struct sockaddr *)&address, + addrlen); } EXPORT_SYMBOL(kernel_bind);