From 054a233306e781ae3cf66b386b67b68e8ac33c37 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Fri, 4 Jun 2021 16:32:55 +0400 Subject: [PATCH 4/6] upd6: check udp6_input buffer size MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fixes: CVE-2021-3593 Fixes: https://gitlab.freedesktop.org/slirp/libslirp/-/issues/45 Signed-off-by: Marc-André Lureau Signed-off-by: imxcc --- slirp/src/udp6.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/slirp/src/udp6.c b/slirp/src/udp6.c index 6f9486bb..8c490e4d 100644 --- a/slirp/src/udp6.c +++ b/slirp/src/udp6.c @@ -28,7 +28,10 @@ void udp6_input(struct mbuf *m) ip = mtod(m, struct ip6 *); m->m_len -= iphlen; m->m_data += iphlen; - uh = mtod(m, struct udphdr *); + uh = mtod_check(m, sizeof(struct udphdr)); + if (uh == NULL) { + goto bad; + } m->m_len += iphlen; m->m_data -= iphlen; -- 2.27.0