From ad30988fde29143951447e7f973918eaa09c448c Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= <philmd@redhat.com>

Date: Wed, 24 Jul 2019 15:53:36 +0100

Subject: [PATCH 11/14] slirp: ensure there is enough space in mbuf to

 null-terminate

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RH-Author: Philippe Mathieu-Daudé <philmd@redhat.com>

Message-id: <20190724155337.25303-4-philmd@redhat.com>

Patchwork-id: 89678

O-Subject: [RHEL-8.1.0 qemu-kvm PATCH v2 3/4] slirp: ensure there is enough space in mbuf to null-terminate

Bugzilla: 1727642

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

RH-Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>

RH-Acked-by: Thomas Huth <thuth@redhat.com>

From: Marc-André Lureau <marcandre.lureau@redhat.com>

Prevents from buffer overflows.

Related to: https://bugzilla.redhat.com/show_bug.cgi?id=1664205

Cc: Prasad J Pandit <pjp@fedoraproject.org>

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

(cherry picked from libslirp commit

306fef58b54d793ba4b259728c21322765bda917)

[ MA - backported with style conflicts fixes ]

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

(cherry picked from commit e80c12dfdbde349dcd225771a4801b47be0b3b5f)

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>

---

 slirp/tcp_subr.c | 3 +++

 1 file changed, 3 insertions(+)

diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c

index 393447d..e245e0d 100644

--- a/slirp/tcp_subr.c

+++ b/slirp/tcp_subr.c

@@ -646,6 +646,7 @@ tcp_emu(struct socket *so, struct mbuf *m)

 			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;

+			m_inc(m, m->m_len + 1);

 			m->m_data[m->m_len] = 0; /* NULL terminate */

 			if (strchr(m->m_data, '\r') || strchr(m->m_data, '\n')) {

 				if (sscanf(so_rcv->sb_data, "%u%*[ ,]%u", &n1, &n2) == 2) {

@@ -679,6 +680,7 @@ tcp_emu(struct socket *so, struct mbuf *m)

 		}

         case EMU_FTP: /* ftp */

+		m_inc(m, m->m_len + 1);

                 *(m->m_data+m->m_len) = 0; /* NUL terminate for strstr */

 		if ((bptr = (char *)strstr(m->m_data, "ORT")) != NULL) {

 			/*

@@ -776,6 +778,7 @@ tcp_emu(struct socket *so, struct mbuf *m)

 		/*

 		 * Need to emulate DCC CHAT, DCC SEND and DCC MOVE

 		 */

+		m_inc(m, m->m_len + 1);

 		*(m->m_data+m->m_len) = 0; /* NULL terminate the string for strstr */

 		if ((bptr = (char *)strstr(m->m_data, "DCC")) == NULL)

 			 return 1;

-- 

1.8.3.1