From 0f8db8cc73df60b3de9a5eebd8f117b56eff5b03 Mon Sep 17 00:00:00 2001 From: Alexey Kodanev Date: Fri, 11 May 2018 20:15:11 +0300 Subject: [PATCH] selinux: add AF_UNSPEC and INADDR_ANY checks to selinux_socket_bind() Commit d452930fd3b9 ("selinux: Add SCTP support") breaks compatibility with the old programs that can pass sockaddr_in structure with AF_UNSPEC and INADDR_ANY to bind(). As a result, bind() returns EAFNOSUPPORT error. This was found with LTP/asapi_01 test. Similar to commit 29c486df6a20 ("net: ipv4: relax AF_INET check in bind()"), which relaxed AF_INET check for compatibility, add AF_UNSPEC case to AF_INET and make sure that the address is INADDR_ANY. Fixes: d452930fd3b9 ("selinux: Add SCTP support") Signed-off-by: Alexey Kodanev Signed-off-by: Paul Moore --- security/selinux/hooks.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 21b377aef69a..16df6cca9a1b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4568,6 +4568,7 @@ static int selinux_socket_post_create(struct socket *sock, int family, static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) { struct sock *sk = sock->sk; + struct sk_security_struct *sksec = sk->sk_security; u16 family; int err; @@ -4579,11 +4580,11 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in family = sk->sk_family; if (family == PF_INET || family == PF_INET6) { char *addrp; - struct sk_security_struct *sksec = sk->sk_security; struct common_audit_data ad; struct lsm_network_audit net = {0,}; struct sockaddr_in *addr4 = NULL; struct sockaddr_in6 *addr6 = NULL; + u16 family_sa = address->sa_family; unsigned short snum; u32 sid, node_perm; @@ -4593,11 +4594,20 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in * need to check address->sa_family as it is possible to have * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. */ - switch (address->sa_family) { + switch (family_sa) { + case AF_UNSPEC: case AF_INET: if (addrlen < sizeof(struct sockaddr_in)) return -EINVAL; addr4 = (struct sockaddr_in *)address; + if (family_sa == AF_UNSPEC) { + /* see __inet_bind(), we only want to allow + * AF_UNSPEC if the address is INADDR_ANY + */ + if (addr4->sin_addr.s_addr != htonl(INADDR_ANY)) + goto err_af; + family_sa = AF_INET; + } snum = ntohs(addr4->sin_port); addrp = (char *)&addr4->sin_addr.s_addr; break; @@ -4609,13 +4619,7 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in addrp = (char *)&addr6->sin6_addr.s6_addr; break; default: - /* Note that SCTP services expect -EINVAL, whereas - * others expect -EAFNOSUPPORT. - */ - if (sksec->sclass == SECCLASS_SCTP_SOCKET) - return -EINVAL; - else - return -EAFNOSUPPORT; + goto err_af; } if (snum) { @@ -4673,7 +4677,7 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in ad.u.net->sport = htons(snum); ad.u.net->family = family; - if (address->sa_family == AF_INET) + if (family_sa == AF_INET) ad.u.net->v4info.saddr = addr4->sin_addr.s_addr; else ad.u.net->v6info.saddr = addr6->sin6_addr; @@ -4686,6 +4690,11 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in } out: return err; +err_af: + /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */ + if (sksec->sclass == SECCLASS_SCTP_SOCKET) + return -EINVAL; + return -EAFNOSUPPORT; } /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) -- GitLab