| Message ID | 20180124010014.2070-2-tom@quantonium.net |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | kcm: fix two syzcaller issues | expand |
On Tue, Jan 23, 2018 at 05:00:13PM -0800, Tom Herbert wrote: > TCP sockets for IPv4 and IPv6 that are not listeners or in closed > stated are allowed to be attached to a KCM mux. > > Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") > Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com > Signed-off-by: Tom Herbert <tom@quantonium.net> > --- > net/kcm/kcmsock.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c > index d4e98f20fc2a..474ea2200592 100644 > --- a/net/kcm/kcmsock.c > +++ b/net/kcm/kcmsock.c > @@ -1391,6 +1391,15 @@ static int kcm_attach(struct socket *sock, struct socket *csock, > if (csk->sk_family == PF_KCM) > return -EOPNOTSUPP; > > + /* Only allow TCP sockets to be attached for now */ > + if ((csk->sk_family != AF_INET && csk->sk_family != AF_INET6) || > + csk->sk_protocol != IPPROTO_TCP) > + return -EOPNOTSUPP; > + This renders the 'csk->sk_family == PF_KCM' test useless. So why not removing it?
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index d4e98f20fc2a..474ea2200592 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1391,6 +1391,15 @@ static int kcm_attach(struct socket *sock, struct socket *csock, if (csk->sk_family == PF_KCM) return -EOPNOTSUPP; + /* Only allow TCP sockets to be attached for now */ + if ((csk->sk_family != AF_INET && csk->sk_family != AF_INET6) || + csk->sk_protocol != IPPROTO_TCP) + return -EOPNOTSUPP; + + /* Don't allow listeners or closed sockets */ + if (csk->sk_state == TCP_LISTEN || csk->sk_state == TCP_CLOSE) + return -EOPNOTSUPP; + psock = kmem_cache_zalloc(kcm_psockp, GFP_KERNEL); if (!psock) return -ENOMEM;
TCP sockets for IPv4 and IPv6 that are not listeners or in closed stated are allowed to be attached to a KCM mux. Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com Signed-off-by: Tom Herbert <tom@quantonium.net> --- net/kcm/kcmsock.c | 9 +++++++++ 1 file changed, 9 insertions(+)