X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=net%2Fcore%2Ffilter.c;h=62667722b5742ca3bb0ef86eee28c86f720b67ac;hp=5dea452792155fffa062a59641c1862e26f19fe0;hb=d0e04e049a62ad9e7371bbd6897f17e56900c48f;hpb=81a3c10ce8a7fd5bf9a06bfc38bd417512911831

diff --git a/net/core/filter.c b/net/core/filter.c
index 5dea45279215..62667722b574 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -64,9 +64,10 @@ static inline void *load_pointer(const struct sk_buff *skb, int k,
 }
 
 /**
- *	sk_filter - run a packet through a socket filter
+ *	sk_filter_trim_cap - run a packet through a socket filter
  *	@sk: sock associated with &sk_buff
  *	@skb: buffer to filter
+ *	@cap: limit on how short the eBPF program may trim the packet
  *
  * Run the filter code and then cut skb->data to correct size returned by
  * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller
@@ -75,7 +76,7 @@ static inline void *load_pointer(const struct sk_buff *skb, int k,
  * be accepted or -EPERM if the packet should be tossed.
  *
  */
-int sk_filter(struct sock *sk, struct sk_buff *skb)
+int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
 {
 	int err;
 	struct sk_filter *filter;
@@ -88,14 +89,13 @@ int sk_filter(struct sock *sk, struct sk_buff *skb)
 	filter = rcu_dereference(sk->sk_filter);
 	if (filter) {
 		unsigned int pkt_len = SK_RUN_FILTER(filter, skb);
-
-		err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
+		err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
 	}
 	rcu_read_unlock();
 
 	return err;
 }
-EXPORT_SYMBOL(sk_filter);
+EXPORT_SYMBOL(sk_filter_trim_cap);
 
 /**
  *	sk_run_filter - run a filter on a socket
@@ -320,6 +320,8 @@ load_b:
 
 			if (skb_is_nonlinear(skb))
 				return 0;
+			if (skb->len < sizeof(struct nlattr))
+				return 0;
 			if (A > skb->len - sizeof(struct nlattr))
 				return 0;
 
@@ -336,11 +338,13 @@ load_b:
 
 			if (skb_is_nonlinear(skb))
 				return 0;
+			if (skb->len < sizeof(struct nlattr))
+				return 0;
 			if (A > skb->len - sizeof(struct nlattr))
 				return 0;
 
 			nla = (struct nlattr *)&skb->data[A];
-			if (nla->nla_len > A - skb->len)
+			if (nla->nla_len > skb->len - A)
 				return 0;
 
 			nla = nla_find_nested(nla, X);