On Wed, May 08, 2019 at 03:32:51PM +0200, Paolo Abeni wrote:
> 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 falling back to the generic/old code when the address family
> is not AF_INET{4,6}, but leave the SCTP code path untouched, as it has
> specific constraints.
>
> Fixes: 68741a8adab9 ("selinux: Fix ltp test connect-syscall failure")
> Reported-by: Tom Deseyn <tdeseyn@xxxxxxxxxx>
> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>
> ---
> security/selinux/hooks.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index c61787b15f27..d82b87c16b0a 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -4649,7 +4649,7 @@ static int selinux_socket_connect_helper(struct socket *sock,
> struct lsm_network_audit net = {0,};
> struct sockaddr_in *addr4 = NULL;
> struct sockaddr_in6 *addr6 = NULL;
> - unsigned short snum;
> + unsigned short snum = 0;
> u32 sid, perm;
>
> /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
> @@ -4674,12 +4674,12 @@ static int selinux_socket_connect_helper(struct socket *sock,
> break;
> default:
> /* Note that SCTP services expect -EINVAL, whereas
> - * others expect -EAFNOSUPPORT.
> + * others must handle this at the protocol level:
> + * connect(AF_UNSPEC) on a connected socket is
> + * a documented way disconnect the socket.
> */
> if (sksec->sclass == SECCLASS_SCTP_SOCKET)
> return -EINVAL;
> - else
> - return -EAFNOSUPPORT;
> }
>
> err = sel_netport_sid(sk->sk_protocol, snum, &sid);
> --
> 2.20.1
>
