From 0f017f39a390d8fa4ae817f45fbf71a0c8332860 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Fri, 4 Jun 2021 16:15:14 +0400 Subject: [PATCH 3/7] bootp: check bootp_input buffer size MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fixes: CVE-2021-3592 Fixes: https://gitlab.freedesktop.org/slirp/libslirp/-/issues/44 Signed-off-by: Marc-André Lureau (cherry picked from commit 2eca0838eee1da96204545e22cdaed860d9d7c6c) --- src/bootp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/bootp.c b/src/bootp.c index e0db8d1..cafa1eb 100644 --- a/src/bootp.c +++ b/src/bootp.c @@ -365,9 +365,9 @@ static void bootp_reply(Slirp *slirp, void bootp_input(struct mbuf *m) { - struct bootp_t *bp = mtod(m, struct bootp_t *); + struct bootp_t *bp = mtod_check(m, sizeof(struct bootp_t)); - if (bp->bp_op == BOOTP_REQUEST) { + if (bp && bp->bp_op == BOOTP_REQUEST) { bootp_reply(m->slirp, bp, m_end(m)); } } -- 2.29.0