On Thu, Apr 26, 2018 at 02:13:57PM +0800, Xin Long wrote:
> Since sctp ipv6 socket also supports v4 addrs, it's possible to
> compare two v4 addrs in pf v6 .cmp_addr, sctp_inet6_cmp_addr.
>
> However after Commit 1071ec9d453a ("sctp: do not check port in
> sctp_inet6_cmp_addr"), it no longer calls af1->cmp_addr, which
> in this case is sctp_v4_cmp_addr, but calls __sctp_v6_cmp_addr
> where it handles them as two v6 addrs. It would cause a out of
> bounds crash.
>
> syzbot found this crash when trying to bind two v4 addrs to a
> v6 socket.
>
> This patch fixes it by adding the process for two v4 addrs in
> sctp_inet6_cmp_addr.
>
> Fixes: 1071ec9d453a ("sctp: do not check port in sctp_inet6_cmp_addr")
> Reported-by: [email protected]
> Signed-off-by: Xin Long <[email protected]>Acked-by: Marcelo Ricardo Leitner <[email protected]> > --- > net/sctp/ipv6.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c > index 2e3f7b7..4224711 100644 > --- a/net/sctp/ipv6.c > +++ b/net/sctp/ipv6.c > @@ -895,6 +895,9 @@ static int sctp_inet6_cmp_addr(const union sctp_addr > *addr1, > if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) > return 1; > > + if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET) > + return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr; > + > return __sctp_v6_cmp_addr(addr1, addr2); > } > > -- > 2.1.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-sctp" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html >
