From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:35427) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gjB7T-00050r-7m for qemu-devel@nongnu.org; Mon, 14 Jan 2019 17:54:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gjB7S-0001rA-67 for qemu-devel@nongnu.org; Mon, 14 Jan 2019 17:54:11 -0500 Received: from hera.aquilenet.fr ([2a0c:e300::1]:37692) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gjB7R-0001ew-Un for qemu-devel@nongnu.org; Mon, 14 Jan 2019 17:54:10 -0500 From: Samuel Thibault Date: Mon, 14 Jan 2019 23:53:06 +0100 Message-Id: <20190114225306.21569-66-samuel.thibault@ens-lyon.org> In-Reply-To: <20190114225306.21569-1-samuel.thibault@ens-lyon.org> References: <20190114225306.21569-1-samuel.thibault@ens-lyon.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL 65/65] slirp: check data length while emulating ident function List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Prasad J Pandit , stefanha@redhat.com, jan.kiszka@siemens.com, Kira <864786842@qq.com>, Samuel Thibault From: Prasad J Pandit While emulating identification protocol, tcp_emu() does not check available space in the 'sc_rcv->sb_data' buffer. It could lead to heap buffer overflow issue. Add check to avoid it. Reported-by: Kira <864786842@qq.com> Signed-off-by: Prasad J Pandit Signed-off-by: Samuel Thibault --- slirp/tcp_subr.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c index 4a9a5b5edc..23a841f26e 100644 --- a/slirp/tcp_subr.c +++ b/slirp/tcp_subr.c @@ -634,6 +634,11 @@ tcp_emu(struct socket *so, struct mbuf *m) socklen_t addrlen =3D sizeof(struct sockaddr_in); struct sbuf *so_rcv =3D &so->so_rcv; =20 + if (m->m_len > so_rcv->sb_datalen + - (so_rcv->sb_wptr - so_rcv->sb_data)) { + return 1; + } + memcpy(so_rcv->sb_wptr, m->m_data, m->m_len); so_rcv->sb_wptr +=3D m->m_len; so_rcv->sb_rptr +=3D m->m_len; --=20 2.20.1