[IPSEC]: Move state lock into x->type->input

This patch releases the lock on the state before calling
x->type->input.  It also adds the lock to the spots where they're
currently needed.

Most of those places (all except mip6) are expected to disappear with
async crypto.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: herbertx

net/ipv4/ah4.c

@@ -169,19 +169,25 @@ static int ah_input(struct xfrm_state *x, struct sk_buff *skb)
 		if (ip_clear_mutable_options(iph, &dummy))
 			goto out;
 	}
+
+	spin_lock(&x->lock);
 	{
 		u8 auth_data[MAX_AH_AUTH_LEN];
 
 		memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len);
 		skb_push(skb, ihl);
 		err = ah_mac_digest(ahp, skb, ah->auth_data);
 		if (err)
-			goto out;
-		if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len)) {
+			goto unlock;
+		if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len))
 			err = -EBADMSG;
-			goto out;
-		}
 	}
+unlock:
+	spin_unlock(&x->lock);
+
+	if (err)
+		goto out;
+
 	skb->network_header += ah_hlen;
 	memcpy(skb_network_header(skb), work_buf, ihl);
 	skb->transport_header = skb->network_header;

net/ipv4/esp4.c

@@ -171,29 +171,31 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
 	if (elen <= 0 || (elen & (blksize-1)))
 		goto out;
 
+	if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
+		goto out;
+	nfrags = err;
+
+	skb->ip_summed = CHECKSUM_NONE;
+
+	spin_lock(&x->lock);
+
 	/* If integrity check is required, do this. */
 	if (esp->auth.icv_full_len) {
 		u8 sum[alen];
 
 		err = esp_mac_digest(esp, skb, 0, skb->len - alen);
 		if (err)
-			goto out;
+			goto unlock;
 
 		if (skb_copy_bits(skb, skb->len - alen, sum, alen))
 			BUG();
 
 		if (unlikely(memcmp(esp->auth.work_icv, sum, alen))) {
 			err = -EBADMSG;
-			goto out;
+			goto unlock;
 		}
 	}
 
-	if ((err = skb_cow_data(skb, 0, &trailer)) < 0)
-		goto out;
-	nfrags = err;
-
-	skb->ip_summed = CHECKSUM_NONE;
-
 	esph = (struct ip_esp_hdr *)skb->data;
 
 	/* Get ivec. This can be wrong, check against another impls. */
@@ -206,7 +208,7 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
 		err = -ENOMEM;
 		sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
 		if (!sg)
-			goto out;
+			goto unlock;
 	}
 	sg_init_table(sg, nfrags);
 	skb_to_sgvec(skb, sg,
@@ -215,6 +217,10 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
 	err = crypto_blkcipher_decrypt(&desc, sg, sg, elen);
 	if (unlikely(sg != &esp->sgbuf[0]))
 		kfree(sg);
+
+unlock:
+	spin_unlock(&x->lock);
+
 	if (unlikely(err))
 		goto out;
 

net/ipv6/ah6.c

@@ -370,6 +370,7 @@ static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
 	ip6h->flow_lbl[2] = 0;
 	ip6h->hop_limit   = 0;
 
+	spin_lock(&x->lock);
 	{
 		u8 auth_data[MAX_AH_AUTH_LEN];
 
@@ -378,13 +379,17 @@ static int ah6_input(struct xfrm_state *x, struct sk_buff *skb)
 		skb_push(skb, hdr_len);
 		err = ah_mac_digest(ahp, skb, ah->auth_data);
 		if (err)
-			goto free_out;
+			goto unlock;
 		if (memcmp(ahp->work_icv, auth_data, ahp->icv_trunc_len)) {
 			LIMIT_NETDEBUG(KERN_WARNING "ipsec ah authentication error\n");
 			err = -EBADMSG;
-			goto free_out;
 		}
 	}
+unlock:
+	spin_unlock(&x->lock);
+
+	if (err)
+		goto free_out;
 
 	skb->network_header += ah_hlen;
 	memcpy(skb_network_header(skb), tmp_hdr, hdr_len);

net/ipv6/esp6.c

@@ -165,30 +165,32 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
 		goto out;
 	}
 
+	if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	skb->ip_summed = CHECKSUM_NONE;
+
+	spin_lock(&x->lock);
+
 	/* If integrity check is required, do this. */
 	if (esp->auth.icv_full_len) {
 		u8 sum[alen];
 
 		ret = esp_mac_digest(esp, skb, 0, skb->len - alen);
 		if (ret)
-			goto out;
+			goto unlock;
 
 		if (skb_copy_bits(skb, skb->len - alen, sum, alen))
 			BUG();
 
 		if (unlikely(memcmp(esp->auth.work_icv, sum, alen))) {
 			ret = -EBADMSG;
-			goto out;
+			goto unlock;
 		}
 	}
 
-	if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	skb->ip_summed = CHECKSUM_NONE;
-
 	esph = (struct ip_esp_hdr *)skb->data;
 	iph = ipv6_hdr(skb);
 
@@ -197,15 +199,13 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
 		crypto_blkcipher_set_iv(tfm, esph->enc_data, esp->conf.ivlen);
 
 	{
-		u8 nexthdr[2];
 		struct scatterlist *sg = &esp->sgbuf[0];
-		u8 padlen;
 
 		if (unlikely(nfrags > ESP_NUM_FAST_SG)) {
 			sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC);
 			if (!sg) {
 				ret = -ENOMEM;
-				goto out;
+				goto unlock;
 			}
 		}
 		sg_init_table(sg, nfrags);
@@ -215,8 +215,17 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
 		ret = crypto_blkcipher_decrypt(&desc, sg, sg, elen);
 		if (unlikely(sg != &esp->sgbuf[0]))
 			kfree(sg);
-		if (unlikely(ret))
-			goto out;
+	}
+
+unlock:
+	spin_unlock(&x->lock);
+
+	if (unlikely(ret))
+		goto out;
+
+	{
+		u8 nexthdr[2];
+		u8 padlen;
 
 		if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
 			BUG();

net/ipv6/mip6.c

@@ -128,12 +128,15 @@ static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	struct ipv6hdr *iph = ipv6_hdr(skb);
 	struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
+	int err = destopt->nexthdr;
 
+	spin_lock(&x->lock);
 	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
 	    !ipv6_addr_any((struct in6_addr *)x->coaddr))
-		return -ENOENT;
+		err = -ENOENT;
+	spin_unlock(&x->lock);
 
-	return destopt->nexthdr;
+	return err;
 }
 
 /* Destination Option Header is inserted.
@@ -344,12 +347,15 @@ static struct xfrm_type mip6_destopt_type =
 static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
+	int err = rt2->rt_hdr.nexthdr;
 
+	spin_lock(&x->lock);
 	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
 	    !ipv6_addr_any((struct in6_addr *)x->coaddr))
-		return -ENOENT;
+		err = -ENOENT;
+	spin_unlock(&x->lock);
 
-	return rt2->rt_hdr.nexthdr;
+	return err;
 }
 
 /* Routing Header type 2 is inserted.

net/xfrm/xfrm_input.c

@@ -146,7 +146,11 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 		if (xfrm_state_check_expire(x))
 			goto drop_unlock;
 
+		spin_unlock(&x->lock);
+
 		nexthdr = x->type->input(x, skb);
+
+		spin_lock(&x->lock);
 		if (nexthdr <= 0) {
 			if (nexthdr == -EBADMSG)
 				x->stats.integrity_failed++;