| Message ID | 20180124203541.3172-2-tom@quantonium.net |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | kcm: fix two syzcaller issues | expand |
On Wed, 2018-01-24 at 12:35 -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, 7 insertions(+), 2 deletions(-) > > diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c > index d4e98f20fc2a..7632797fb68e 100644 > --- a/net/kcm/kcmsock.c > +++ b/net/kcm/kcmsock.c > @@ -1387,8 +1387,13 @@ static int kcm_attach(struct socket *sock, struct socket *csock, > if (!csk) > return -EINVAL; > > - /* We must prevent loops or risk deadlock ! */ > - if (csk->sk_family == PF_KCM) > + /* 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); Reviewed-by: Eric Dumazet <edumazet@google.com>
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index d4e98f20fc2a..7632797fb68e 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1387,8 +1387,13 @@ static int kcm_attach(struct socket *sock, struct socket *csock, if (!csk) return -EINVAL; - /* We must prevent loops or risk deadlock ! */ - if (csk->sk_family == PF_KCM) + /* 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);
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, 7 insertions(+), 2 deletions(-)