Commit ecaae08d authored Apr 23, 2018 by Guillaume Nault Committed by Greg Kroah-Hartman Apr 29, 2018

pppoe: check sockaddr length in pppoe_connect()




[ Upstream commit a49e2f5d5fb141884452ddb428f551b123d436b5 ]

We must validate sockaddr_len, otherwise userspace can pass fewer data
than we expect and we end up accessing invalid data.

Fixes: 224cf5ad ("ppp: Move the PPP drivers")
Reported-by:  <syzbot+4f03bdf92fdf9ef5ddab@syzkaller.appspotmail.com>
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 0b6693b4

drivers/net/ppp/pppoe.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -620,6 +620,10 @@ static int pppoe_connect(struct socket sock, struct sockaddr uservaddr,
		lock_sock(sk);

		error = -EINVAL;

		if (sockaddr_len != sizeof(struct sockaddr_pppox))
		goto end;

		if (sp->sa_protocol != PX_PROTO_OE)
		goto end;