From owner-svn-src-all@freebsd.org Fri Jun 23 10:09:50 2017 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 64ACADA131B; Fri, 23 Jun 2017 10:09:50 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 3547B7FC3B; Fri, 23 Jun 2017 10:09:50 +0000 (UTC) (envelope-from tuexen@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v5NA9nwb049469; Fri, 23 Jun 2017 10:09:49 GMT (envelope-from tuexen@FreeBSD.org) Received: (from tuexen@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v5NA9noQ049468; Fri, 23 Jun 2017 10:09:49 GMT (envelope-from tuexen@FreeBSD.org) Message-Id: <201706231009.v5NA9noQ049468@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: tuexen set sender to tuexen@FreeBSD.org using -f From: Michael Tuexen Date: Fri, 23 Jun 2017 10:09:49 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r320264 - head/sys/netinet X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Jun 2017 10:09:50 -0000 Author: tuexen Date: Fri Jun 23 10:09:49 2017 New Revision: 320264 URL: https://svnweb.freebsd.org/changeset/base/320264 Log: Check the length of a COOKIE chunk before accessing fields in it. Thanks to Felix Weinrank for reporting the issue he found by using libFuzzer. MFC after: 3 days Modified: head/sys/netinet/sctp_input.c Modified: head/sys/netinet/sctp_input.c ============================================================================== --- head/sys/netinet/sctp_input.c Fri Jun 23 09:27:31 2017 (r320263) +++ head/sys/netinet/sctp_input.c Fri Jun 23 10:09:49 2017 (r320264) @@ -2441,6 +2441,12 @@ sctp_handle_cookie_echo(struct mbuf *m, int iphlen, in cookie_offset = offset + sizeof(struct sctp_chunkhdr); cookie_len = ntohs(cp->ch.chunk_length); + if (cookie_len < sizeof(struct sctp_cookie_echo_chunk) + + sizeof(struct sctp_init_chunk) + + sizeof(struct sctp_init_ack_chunk) + SCTP_SIGNATURE_SIZE) { + /* cookie too small */ + return (NULL); + } if ((cookie->peerport != sh->src_port) || (cookie->myport != sh->dest_port) || (cookie->my_vtag != sh->v_tag)) { @@ -2451,12 +2457,6 @@ sctp_handle_cookie_echo(struct mbuf *m, int iphlen, in * This maintains the match even though it may be in the * opposite byte order of the machine :-> */ - return (NULL); - } - if (cookie_len < sizeof(struct sctp_cookie_echo_chunk) + - sizeof(struct sctp_init_chunk) + - sizeof(struct sctp_init_ack_chunk) + SCTP_SIGNATURE_SIZE) { - /* cookie too small */ return (NULL); } /*