[PATCH net-next v9 2/5] ipsec: check return value of skb_to_sgvec always

[Jason A. Donenfeld]

Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Cc: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
---
 net/ipv4/ah4.c  |  8 ++++++--
 net/ipv4/esp4.c | 20 +++++++++++++-------
 net/ipv6/ah6.c  |  8 ++++++--
 net/ipv6/esp6.c | 20 +++++++++++++-------
 4 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c
index 22377c8ff14b..e8f862358518 100644
--- a/net/ipv4/ah4.c
+++ b/net/ipv4/ah4.c
@@ -220,7 +220,9 @@ static int ah_output(struct xfrm_state *x, struct sk_buff *skb)
 	ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
 
 	sg_init_table(sg, nfrags + sglists);
-	skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	err = skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	if (unlikely(err < 0))
+		goto out_free;
 
 	if (x->props.flags & XFRM_STATE_ESN) {
 		/* Attach seqhi sg right after packet payload */
@@ -393,7 +395,9 @@ static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
 	skb_push(skb, ihl);
 
 	sg_init_table(sg, nfrags + sglists);
-	skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	err = skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	if (unlikely(err < 0))
+		goto out_free;
 
 	if (x->props.flags & XFRM_STATE_ESN) {
 		/* Attach seqhi sg right after packet payload */
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 65cc02bd82bc..392432860bb9 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -374,9 +374,11 @@ int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *
 	esp->esph = esph;
 
 	sg_init_table(sg, esp->nfrags);
-	skb_to_sgvec(skb, sg,
-		     (unsigned char *)esph - skb->data,
-		     assoclen + ivlen + esp->clen + alen);
+	err = skb_to_sgvec(skb, sg,
+		           (unsigned char *)esph - skb->data,
+		           assoclen + ivlen + esp->clen + alen);
+	if (unlikely(err < 0))
+		goto error;
 
 	if (!esp->inplace) {
 		int allocsize;
@@ -400,9 +402,11 @@ int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *
 		spin_unlock_bh(&x->lock);
 
 		sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
-		skb_to_sgvec(skb, dsg,
-			     (unsigned char *)esph - skb->data,
-			     assoclen + ivlen + esp->clen + alen);
+		err = skb_to_sgvec(skb, dsg,
+			           (unsigned char *)esph - skb->data,
+			           assoclen + ivlen + esp->clen + alen);
+		if (unlikely(err < 0))
+			goto error;
 	}
 
 	if ((x->props.flags & XFRM_STATE_ESN))
@@ -687,7 +691,9 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
 	esp_input_set_header(skb, seqhi);
 
 	sg_init_table(sg, nfrags);
-	skb_to_sgvec(skb, sg, 0, skb->len);
+	err = skb_to_sgvec(skb, sg, 0, skb->len);
+	if (unlikely(err < 0))
+		goto out;
 
 	skb->ip_summed = CHECKSUM_NONE;
 
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index dda6035e3b84..755f38271dd5 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -423,7 +423,9 @@ static int ah6_output(struct xfrm_state *x, struct sk_buff *skb)
 	ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
 
 	sg_init_table(sg, nfrags + sglists);
-	skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	err = skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	if (unlikely(err < 0))
+		goto out_free;
 
 	if (x->props.flags & XFRM_STATE_ESN) {
 		/* Attach seqhi sg right after packet payload */
@@ -606,7 +608,9 @@ static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
 	ip6h->hop_limit   = 0;
 
 	sg_init_table(sg, nfrags + sglists);
-	skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	err = skb_to_sgvec_nomark(skb, sg, 0, skb->len);
+	if (unlikely(err < 0))
+		goto out_free;
 
 	if (x->props.flags & XFRM_STATE_ESN) {
 		/* Attach seqhi sg right after packet payload */
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 1fe99ba8066c..2ede4e459c4e 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -346,9 +346,11 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info
 	esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi);
 
 	sg_init_table(sg, esp->nfrags);
-	skb_to_sgvec(skb, sg,
-		     (unsigned char *)esph - skb->data,
-		     assoclen + ivlen + esp->clen + alen);
+	err = skb_to_sgvec(skb, sg,
+		           (unsigned char *)esph - skb->data,
+		           assoclen + ivlen + esp->clen + alen);
+	if (unlikely(err < 0))
+		goto error;
 
 	if (!esp->inplace) {
 		int allocsize;
@@ -372,9 +374,11 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info
 		spin_unlock_bh(&x->lock);
 
 		sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
-		skb_to_sgvec(skb, dsg,
-			     (unsigned char *)esph - skb->data,
-			     assoclen + ivlen + esp->clen + alen);
+		err = skb_to_sgvec(skb, dsg,
+			           (unsigned char *)esph - skb->data,
+			           assoclen + ivlen + esp->clen + alen);
+		if (unlikely(err < 0))
+			goto error;
 	}
 
 	if ((x->props.flags & XFRM_STATE_ESN))
@@ -618,7 +622,9 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
 	esp_input_set_header(skb, seqhi);
 
 	sg_init_table(sg, nfrags);
-	skb_to_sgvec(skb, sg, 0, skb->len);
+	ret = skb_to_sgvec(skb, sg, 0, skb->len);
+	if (unlikely(ret < 0))
+		goto out;
 
 	skb->ip_summed = CHECKSUM_NONE;
 
-- 
2.13.0