Commit 4e74e7a8 authored by Prasad J Pandit's avatar Prasad J Pandit Committed by Michael Roth
Browse files

slirp: check data length while emulating ident function 



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: default avatarKira <864786842@qq.com>
Signed-off-by: default avatarPrasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: default avatarSamuel Thibault <samuel.thibault@ens-lyon.org>
(cherry picked from commit a7104eda)
Signed-off-by: default avatarMichael Roth <mdroth@linux.vnet.ibm.com>
parent 375667af

slirp/tcp_subr.c

+5 −0
Original line number Diff line number Diff line
@@ -635,6 +635,11 @@ tcp_emu(struct socket *so, struct mbuf *m) 
			socklen_t addrlen = sizeof(struct sockaddr_in);

			struct sbuf *so_rcv = &so->so_rcv;



			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 += m->m_len;

			so_rcv->sb_rptr += m->m_len;