calling connect(AF_UNSPEC) on an already connected TCP socket is an established way to disconnect() such socket. After commit 68741a8adab9 ("selinux: Fix ltp test connect-syscall failure") it no longer works and, in the above scenario connect() fails with EAFNOSUPPORT. Fix the above explicitly early checking for AF_UNSPEC family, and returning success in that case. Suggested-by: Paul Moore <paul@xxxxxxxxxxxxxx> Fixes: 68741a8adab9 ("selinux: Fix ltp test connect-syscall failure") Reported-by: Tom Deseyn <tdeseyn@xxxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> --- v2 -> v3: - do the check for AF_UNSPEC at the begining, as suggested by Paul v1 -> v2: - avoid validation for AF_UNSPEC --- security/selinux/hooks.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index c61787b15f27..3ec702cf46ca 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4637,6 +4637,14 @@ static int selinux_socket_connect_helper(struct socket *sock, err = sock_has_perm(sk, SOCKET__CONNECT); if (err) return err; + if (addrlen < offsetofend(struct sockaddr, sa_family)) + return -EINVAL; + + /* connect(AF_UNSPEC) has special handling, as it is a documented + * way to disconnect the socket + */ + if (address->sa_family == AF_UNSPEC) + return 0; /* * If a TCP, DCCP or SCTP socket, check name_connect permission @@ -4657,8 +4665,6 @@ static int selinux_socket_connect_helper(struct socket *sock, * need to check address->sa_family as it is possible to have * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET. */ - if (addrlen < offsetofend(struct sockaddr, sa_family)) - return -EINVAL; switch (address->sa_family) { case AF_INET: addr4 = (struct sockaddr_in *)address; -- 2.20.1