pptp: verify sockaddr_len in pptp_bind() and pptp_connect() (CVE-2015-8569)

debian/changelog

@@ -3,6 +3,7 @@ linux (4.3.3-3) UNRELEASED; urgency=medium
   [ Ben Hutchings ]
   * [ppc64*] drm: Enable DRM_AST as module (Closes: #808338)
   * block: ensure to split after potentially bouncing a bio (Closes: #809082)
+  * pptp: verify sockaddr_len in pptp_bind() and pptp_connect() (CVE-2015-8569)
 
   [ Salvatore Bonaccorso ]
   * ovl: fix permission checking for setattr (CVE-2015-8660)

debian/patches/bugfix/all/pptp-verify-sockaddr_len-in-pptp_bind-and-pptp_conne.patch

@@ -0,0 +1,34 @@
+From: WANG Cong <xiyou.wangcong@gmail.com>
+Date: Mon, 14 Dec 2015 13:48:36 -0800
+Subject: pptp: verify sockaddr_len in pptp_bind() and pptp_connect()
+Origin: https://git.kernel.org/linus/09ccfd238e5a0e670d8178cf50180ea81ae09ae1
+
+Reported-by: Dmitry Vyukov <dvyukov@gmail.com>
+Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ppp/pptp.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+--- a/drivers/net/ppp/pptp.c
++++ b/drivers/net/ppp/pptp.c
+@@ -418,6 +418,9 @@ static int pptp_bind(struct socket *sock
+ 	struct pptp_opt *opt = &po->proto.pptp;
+ 	int error = 0;
+ 
++	if (sockaddr_len < sizeof(struct sockaddr_pppox))
++		return -EINVAL;
++
+ 	lock_sock(sk);
+ 
+ 	opt->src_addr = sp->sa_addr.pptp;
+@@ -439,6 +442,9 @@ static int pptp_connect(struct socket *s
+ 	struct flowi4 fl4;
+ 	int error = 0;
+ 
++	if (sockaddr_len < sizeof(struct sockaddr_pppox))
++		return -EINVAL;
++
+ 	if (sp->sa_protocol != PX_PROTO_PPTP)
+ 		return -EINVAL;
+ 

debian/patches/series

@@ -107,3 +107,4 @@ bugfix/all/tipc-fix-kfree_skb-of-uninitialised-pointer.patch
 debian/armhf-sparc64-force-zone_dma-to-be-enabled.patch
 bugfix/all/ovl-fix-permission-checking-for-setattr.patch
 bugfix/all/block-ensure-to-split-after-potentially-bouncing-a-b.patch
+bugfix/all/pptp-verify-sockaddr_len-in-pptp_bind-and-pptp_conne.patch