[LLC]: bogus llc packet length
discard llc packet which has bogus packet length.
Signed-off-by: Joonwoo Park <joonwpark81@gmail.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/llc/llc_input.c b/net/llc/llc_input.c
index c40c9b2..bfd2567 100644
--- a/net/llc/llc_input.c
+++ b/net/llc/llc_input.c
@@ -117,8 +117,12 @@
skb_pull(skb, llc_len);
if (skb->protocol == htons(ETH_P_802_2)) {
__be16 pdulen = eth_hdr(skb)->h_proto;
- u16 data_size = ntohs(pdulen) - llc_len;
+ s32 data_size = ntohs(pdulen) - llc_len;
+ if (data_size < 0 ||
+ ((skb_tail_pointer(skb) -
+ (u8 *)pdu) - llc_len) < data_size)
+ return 0;
if (unlikely(pskb_trim_rcsum(skb, data_size)))
return 0;
}