From 0f7224535cdfec549cd43a5ae4ccde936f50ee95 Mon Sep 17 00:00:00 2001 From: Samuel Thibault Date: Wed, 11 Mar 2020 17:33:46 +0800 Subject: [PATCH] tcp_emu: Fix oob access The main loop only checks for one available byte, while we sometimes need two bytes. --- slirp/src/tcp_subr.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/slirp/src/tcp_subr.c b/slirp/src/tcp_subr.c index fde9207b..4608942f 100644 --- a/slirp/src/tcp_subr.c +++ b/slirp/src/tcp_subr.c @@ -895,6 +895,9 @@ tcp_emu(struct socket *so, struct mbuf *m) break; case 5: + if (bptr == m->m_data + m->m_len - 1) + return 1; /* We need two bytes */ + /* * The difference between versions 1.0 and * 2.0 is here. For future versions of @@ -910,6 +913,9 @@ tcp_emu(struct socket *so, struct mbuf *m) /* This is the field containing the port * number that RA-player is listening to. */ + if (bptr == m->m_data + m->m_len - 1) + return 1; /* We need two bytes */ + lport = (((uint8_t*)bptr)[0] << 8) + ((uint8_t *)bptr)[1]; if (lport < 6970) -- 2.21.1 (Apple Git-122.3)