4 files changed, 18 insertions, 3 deletions
diff --git a/net/sched/em_canid.c b/net/sched/em_canid.c
index 5337bc462755..2d27f91d8441 100644
--- a/net/sched/em_canid.c
+++ b/net/sched/em_canid.c
@@ -99,6 +99,9 @@ static int em_canid_match(struct sk_buff *skb, struct tcf_ematch *m,
 	int i;
 	const struct can_filter *lp;
 
+	if (!pskb_may_pull(skb, CAN_MTU))
+		return 0;
+
 	can_id = em_canid_get_id(skb);
 
 	if (can_id & CAN_EFF_FLAG) {
diff --git a/net/sched/em_cmp.c b/net/sched/em_cmp.c
index 64b637f18bc7..48c1bce74f49 100644
--- a/net/sched/em_cmp.c
+++ b/net/sched/em_cmp.c
@@ -22,9 +22,12 @@ static int em_cmp_match(struct sk_buff *skb, struct tcf_ematch *em,
 			struct tcf_pkt_info *info)
 {
 	struct tcf_em_cmp *cmp = (struct tcf_em_cmp *) em->data;
-	unsigned char *ptr = tcf_get_base_ptr(skb, cmp->layer) + cmp->off;
+	unsigned char *ptr = tcf_get_base_ptr(skb, cmp->layer);
 	u32 val = 0;
 
+	if (!ptr)
+		return 0;
+	ptr += cmp->off;
 	if (!tcf_valid_offset(skb, ptr, cmp->align))
 		return 0;
 
diff --git a/net/sched/em_nbyte.c b/net/sched/em_nbyte.c
index 4f9f21a05d5e..c65ffa5fff94 100644
--- a/net/sched/em_nbyte.c
+++ b/net/sched/em_nbyte.c
@@ -42,6 +42,8 @@ static int em_nbyte_match(struct sk_buff *skb, struct tcf_ematch *em,
 	struct nbyte_data *nbyte = (struct nbyte_data *) em->data;
 	unsigned char *ptr = tcf_get_base_ptr(skb, nbyte->hdr.layer);
 
+	if (!ptr)
+		return 0;
 	ptr += nbyte->hdr.off;
 
 	if (!tcf_valid_offset(skb, ptr, nbyte->hdr.len))
diff --git a/net/sched/em_text.c b/net/sched/em_text.c
index 6b3d0af72c39..692e2be1793e 100644
--- a/net/sched/em_text.c
+++ b/net/sched/em_text.c
@@ -29,12 +29,19 @@ static int em_text_match(struct sk_buff *skb, struct tcf_ematch *m,
 			 struct tcf_pkt_info *info)
 {
 	struct text_match *tm = EM_TEXT_PRIV(m);
+	unsigned char *ptr;
 	int from, to;
 
-	from = tcf_get_base_ptr(skb, tm->from_layer) - skb->data;
+	ptr = tcf_get_base_ptr(skb, tm->from_layer);
+	if (!ptr)
+		return 0;
+	from = ptr - skb->data;
 	from += tm->from_offset;
 
-	to = tcf_get_base_ptr(skb, tm->to_layer) - skb->data;
+	ptr = tcf_get_base_ptr(skb, tm->to_layer);
+	if (!ptr)
+		return 0;
+	to = ptr - skb->data;
 	to += tm->to_offset;
 
 	return skb_find_text(skb, from, to, tm->config) != UINT_MAX;