[B.A.T.M.A.N.] [PATCH 01/14] batman-adv: fix wrong dhcp option list browsing

Antonio Quartulli
2012-05-09T11:12:43Z

In is_type_dhcprequest(), while parsing a DHCP message, if the entry we found in
the option list is neither a padding nor the dhcp-type, we have to ignore it and
jump as many bytes as its length + 1. The "+ 1" byte is given by the subtype
field itself that has to be jumped too.

Reported-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
---
net/batman-adv/gateway_client.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index 6f9b9b7..47f7186 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -558,10 +558,10 @@ static bool is_type_dhcprequest(struct sk_buff *skb, int header_len)
p++;

/* ...and then we jump over the data */
- if (pkt_len < *p)
+ if (pkt_len < 1 + (*p))
goto out;
- pkt_len -= *p;
- p += (*p);
+ pkt_len -= 1 + (*p);
+ p += 1 + (*p);
}
}
out:
--
1.7.9.4