This is a note to let you know that I've just added the patch titled net: prevent address rewrite in kernel_bind() to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-prevent-address-rewrite-in-kernel_bind.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c889a99a21bf124c3db08d09df919f0eccc5ea4c Mon Sep 17 00:00:00 2001 From: Jordan Rife <jrife@xxxxxxxxxx> Date: Thu, 21 Sep 2023 18:46:42 -0500 Subject: net: prevent address rewrite in kernel_bind() From: Jordan Rife <jrife@xxxxxxxxxx> commit c889a99a21bf124c3db08d09df919f0eccc5ea4c upstream. 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@xxxxxxxxxx/ Fixes: 4fbac77d2d09 ("bpf: Hooks for sys_bind") Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx> Signed-off-by: Jordan Rife <jrife@xxxxxxxxxx> Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/ipvs/ip_vs_sync.c | 4 ++-- net/rds/tcp_connect.c | 2 +- net/rds/tcp_listen.c | 2 +- net/socket.c | 6 +++++- 4 files changed, 9 insertions(+), 5 deletions(-) --- a/net/netfilter/ipvs/ip_vs_sync.c +++ b/net/netfilter/ipvs/ip_vs_sync.c @@ -1444,7 +1444,7 @@ static int bind_mcastif_addr(struct sock 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, @@ -1551,7 +1551,7 @@ static int make_receive_sock(struct netn 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; --- a/net/rds/tcp_connect.c +++ b/net/rds/tcp_connect.c @@ -141,7 +141,7 @@ int rds_tcp_conn_path_connect(struct rds 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); --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -332,7 +332,7 @@ struct socket *rds_tcp_listen_init(struc 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); --- a/net/socket.c +++ b/net/socket.c @@ -3427,7 +3427,11 @@ static long compat_sock_ioctl(struct fil int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen) { - return sock->ops->bind(sock, addr, addrlen); + struct sockaddr_storage address; + + memcpy(&address, addr, addrlen); + + return sock->ops->bind(sock, (struct sockaddr *)&address, addrlen); } EXPORT_SYMBOL(kernel_bind); Patches currently in stable-queue which might be from jrife@xxxxxxxxxx are queue-4.19/net-prevent-rewrite-of-msg_name-in-sock_sendmsg.patch queue-4.19/net-prevent-address-rewrite-in-kernel_bind.patch