From 2294be0f11e22b6197d025e5d3ab42888879ec4e Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 18 Dec 2018 17:15:20 +0100
Subject: [PATCH] net: use skb_sec_path helper in more places

skb_sec_path gains 'const' qualifier to avoid
xt_policy.c: 'skb_sec_path' discards 'const' qualifier from pointer target type

same reasoning as previous conversions: Won't need to touch these
spots anymore when skb->sp is removed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 include/linux/skbuff.h    |  2 +-
 include/net/xfrm.h        |  6 ++++--
 net/ipv4/esp4.c           |  9 ++++++---
 net/ipv4/esp4_offload.c   |  4 +++-
 net/ipv6/esp6.c           |  9 ++++++---
 net/ipv6/esp6_offload.c   |  4 +++-
 net/ipv6/xfrm6_input.c    |  2 +-
 net/netfilter/nft_xfrm.c  |  2 +-
 net/netfilter/xt_policy.c |  2 +-
 net/xfrm/xfrm_device.c    |  4 +++-
 net/xfrm/xfrm_input.c     | 16 ++++++++++------
 net/xfrm/xfrm_policy.c    | 19 +++++++++++--------
 security/selinux/xfrm.c   |  4 ++--
 13 files changed, 52 insertions(+), 31 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 70ac58240ec0..d0f254a016bf 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -4124,7 +4124,7 @@ static inline bool skb_get_dst_pending_confirm(const struct sk_buff *skb)
 	return skb->dst_pending_confirm != 0;
 }
 
-static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
+static inline struct sec_path *skb_sec_path(const struct sk_buff *skb)
 {
 #ifdef CONFIG_XFRM
 	return skb->sp;
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 9cb506d09b98..af723448c972 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1896,14 +1896,16 @@ static inline void xfrm_states_delete(struct xfrm_state **states, int n)
 #ifdef CONFIG_XFRM
 static inline struct xfrm_state *xfrm_input_state(struct sk_buff *skb)
 {
-	return skb->sp->xvec[skb->sp->len - 1];
+	struct sec_path *sp = skb_sec_path(skb);
+
+	return sp->xvec[sp->len - 1];
 }
 #endif
 
 static inline struct xfrm_offload *xfrm_offload(struct sk_buff *skb)
 {
 #ifdef CONFIG_XFRM
-	struct sec_path *sp = skb->sp;
+	struct sec_path *sp = skb_sec_path(skb);
 
 	if (!sp || !sp->olen || sp->len != sp->olen)
 		return NULL;
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 9e1c840596c5..5459f41fc26f 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -125,10 +125,13 @@ static void esp_output_done(struct crypto_async_request *base, int err)
 	void *tmp;
 	struct xfrm_state *x;
 
-	if (xo && (xo->flags & XFRM_DEV_RESUME))
-		x = skb->sp->xvec[skb->sp->len - 1];
-	else
+	if (xo && (xo->flags & XFRM_DEV_RESUME)) {
+		struct sec_path *sp = skb_sec_path(skb);
+
+		x = sp->xvec[sp->len - 1];
+	} else {
 		x = skb_dst(skb)->xfrm;
+	}
 
 	tmp = ESP_SKB_CB(skb)->tmp;
 	esp_ssg_unref(x, tmp);
diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c
index 19bd22aa05f9..8756e0e790d2 100644
--- a/net/ipv4/esp4_offload.c
+++ b/net/ipv4/esp4_offload.c
@@ -115,6 +115,7 @@ static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
 	struct crypto_aead *aead;
 	netdev_features_t esp_features = features;
 	struct xfrm_offload *xo = xfrm_offload(skb);
+	struct sec_path *sp;
 
 	if (!xo)
 		return ERR_PTR(-EINVAL);
@@ -122,7 +123,8 @@ static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
 	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
 		return ERR_PTR(-EINVAL);
 
-	x = skb->sp->xvec[skb->sp->len - 1];
+	sp = skb_sec_path(skb);
+	x = sp->xvec[sp->len - 1];
 	aead = x->data;
 	esph = ip_esp_hdr(skb);
 
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 63b2b66f9dfa..5afe9f83374d 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -145,10 +145,13 @@ static void esp_output_done(struct crypto_async_request *base, int err)
 	void *tmp;
 	struct xfrm_state *x;
 
-	if (xo && (xo->flags & XFRM_DEV_RESUME))
-		x = skb->sp->xvec[skb->sp->len - 1];
-	else
+	if (xo && (xo->flags & XFRM_DEV_RESUME)) {
+		struct sec_path *sp = skb_sec_path(skb);
+
+		x = sp->xvec[sp->len - 1];
+	} else {
 		x = skb_dst(skb)->xfrm;
+	}
 
 	tmp = ESP_SKB_CB(skb)->tmp;
 	esp_ssg_unref(x, tmp);
diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index 01a97f5dfa4e..d46b4eb645c2 100644
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -142,6 +142,7 @@ static struct sk_buff *esp6_gso_segment(struct sk_buff *skb,
 	struct crypto_aead *aead;
 	netdev_features_t esp_features = features;
 	struct xfrm_offload *xo = xfrm_offload(skb);
+	struct sec_path *sp;
 
 	if (!xo)
 		return ERR_PTR(-EINVAL);
@@ -149,7 +150,8 @@ static struct sk_buff *esp6_gso_segment(struct sk_buff *skb,
 	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
 		return ERR_PTR(-EINVAL);
 
-	x = skb->sp->xvec[skb->sp->len - 1];
+	sp = skb_sec_path(skb);
+	x = sp->xvec[sp->len - 1];
 	aead = x->data;
 	esph = ip_esp_hdr(skb);
 
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 97c69df1b329..a52cb3fc6df5 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -147,7 +147,7 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
 		goto drop;
 	}
 
-	skb->sp->xvec[skb->sp->len++] = x;
+	sp->xvec[sp->len++] = x;
 
 	spin_lock(&x->lock);
 
diff --git a/net/netfilter/nft_xfrm.c b/net/netfilter/nft_xfrm.c
index 5322609f7662..b08865ec5ed3 100644
--- a/net/netfilter/nft_xfrm.c
+++ b/net/netfilter/nft_xfrm.c
@@ -161,7 +161,7 @@ static void nft_xfrm_get_eval_in(const struct nft_xfrm *priv,
 				    struct nft_regs *regs,
 				    const struct nft_pktinfo *pkt)
 {
-	const struct sec_path *sp = pkt->skb->sp;
+	const struct sec_path *sp = skb_sec_path(pkt->skb);
 	const struct xfrm_state *state;
 
 	if (sp == NULL || sp->len <= priv->spnum) {
diff --git a/net/netfilter/xt_policy.c b/net/netfilter/xt_policy.c
index 13f8ccf946d6..aa84e8121c93 100644
--- a/net/netfilter/xt_policy.c
+++ b/net/netfilter/xt_policy.c
@@ -56,7 +56,7 @@ match_policy_in(const struct sk_buff *skb, const struct xt_policy_info *info,
 		unsigned short family)
 {
 	const struct xt_policy_elem *e;
-	const struct sec_path *sp = skb->sp;
+	const struct sec_path *sp = skb_sec_path(skb);
 	int strict = info->flags & XT_POLICY_MATCH_STRICT;
 	int i, pos;
 
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index 144c137886b1..b8736f56e7f7 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -32,6 +32,7 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur
 	struct softnet_data *sd;
 	netdev_features_t esp_features = features;
 	struct xfrm_offload *xo = xfrm_offload(skb);
+	struct sec_path *sp;
 
 	if (!xo)
 		return skb;
@@ -39,7 +40,8 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur
 	if (!(features & NETIF_F_HW_ESP))
 		esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
 
-	x = skb->sp->xvec[skb->sp->len - 1];
+	sp = skb_sec_path(skb);
+	x = sp->xvec[sp->len - 1];
 	if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
 		return skb;
 
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index bda929b9ff35..b4db25b244fa 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -330,7 +330,9 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 	daddr = (xfrm_address_t *)(skb_network_header(skb) +
 				   XFRM_SPI_SKB_CB(skb)->daddroff);
 	do {
-		if (skb->sp->len == XFRM_MAX_DEPTH) {
+		sp = skb_sec_path(skb);
+
+		if (sp->len == XFRM_MAX_DEPTH) {
 			secpath_reset(skb);
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 			goto drop;
@@ -346,7 +348,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 
 		skb->mark = xfrm_smark_get(skb->mark, x);
 
-		skb->sp->xvec[skb->sp->len++] = x;
+		sp->xvec[sp->len++] = x;
 
 lock:
 		spin_lock(&x->lock);
@@ -470,8 +472,9 @@ resume:
 	nf_reset(skb);
 
 	if (decaps) {
-		if (skb->sp)
-			skb->sp->olen = 0;
+		sp = skb_sec_path(skb);
+		if (sp)
+			sp->olen = 0;
 		skb_dst_drop(skb);
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
@@ -482,8 +485,9 @@ resume:
 
 		err = x->inner_mode->afinfo->transport_finish(skb, xfrm_gro || async);
 		if (xfrm_gro) {
-			if (skb->sp)
-				skb->sp->olen = 0;
+			sp = skb_sec_path(skb);
+			if (sp)
+				sp->olen = 0;
 			skb_dst_drop(skb);
 			gro_cells_receive(&gro_cells, skb);
 			return err;
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index be04091eb7db..d6acba07bdc9 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -3200,11 +3200,12 @@ EXPORT_SYMBOL(xfrm_lookup_route);
 static inline int
 xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
 {
+	struct sec_path *sp = skb_sec_path(skb);
 	struct xfrm_state *x;
 
-	if (!skb->sp || idx < 0 || idx >= skb->sp->len)
+	if (!sp || idx < 0 || idx >= sp->len)
 		return 0;
-	x = skb->sp->xvec[idx];
+	x = sp->xvec[idx];
 	if (!x->type->reject)
 		return 0;
 	return x->type->reject(x, skb, fl);
@@ -3304,6 +3305,7 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 	struct flowi fl;
 	int xerr_idx = -1;
 	const struct xfrm_if_cb *ifcb;
+	struct sec_path *sp;
 	struct xfrm_if *xi;
 	u32 if_id = 0;
 
@@ -3328,11 +3330,12 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 	nf_nat_decode_session(skb, &fl, family);
 
 	/* First, check used SA against their selectors. */
-	if (skb->sp) {
+	sp = skb_sec_path(skb);
+	if (sp) {
 		int i;
 
-		for (i = skb->sp->len-1; i >= 0; i--) {
-			struct xfrm_state *x = skb->sp->xvec[i];
+		for (i = sp->len - 1; i >= 0; i--) {
+			struct xfrm_state *x = sp->xvec[i];
 			if (!xfrm_selector_match(&x->sel, &fl, family)) {
 				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
 				return 0;
@@ -3359,7 +3362,7 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 	}
 
 	if (!pol) {
-		if (skb->sp && secpath_has_nontransport(skb->sp, 0, &xerr_idx)) {
+		if (sp && secpath_has_nontransport(sp, 0, &xerr_idx)) {
 			xfrm_secpath_reject(xerr_idx, skb, &fl);
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
 			return 0;
@@ -3388,7 +3391,6 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 #endif
 
 	if (pol->action == XFRM_POLICY_ALLOW) {
-		struct sec_path *sp;
 		static struct sec_path dummy;
 		struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
 		struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
@@ -3396,7 +3398,8 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
 		int ti = 0;
 		int i, k;
 
-		if ((sp = skb->sp) == NULL)
+		sp = skb_sec_path(skb);
+		if (!sp)
 			sp = &dummy;
 
 		for (pi = 0; pi < npols; pi++) {
diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c
index 91dc3783ed94..bd7d18bdb147 100644
--- a/security/selinux/xfrm.c
+++ b/security/selinux/xfrm.c
@@ -230,7 +230,7 @@ static int selinux_xfrm_skb_sid_ingress(struct sk_buff *skb,
 					u32 *sid, int ckall)
 {
 	u32 sid_session = SECSID_NULL;
-	struct sec_path *sp = skb->sp;
+	struct sec_path *sp = skb_sec_path(skb);
 
 	if (sp) {
 		int i;
@@ -408,7 +408,7 @@ int selinux_xfrm_sock_rcv_skb(u32 sk_sid, struct sk_buff *skb,
 			      struct common_audit_data *ad)
 {
 	int i;
-	struct sec_path *sp = skb->sp;
+	struct sec_path *sp = skb_sec_path(skb);
 	u32 peer_sid = SECINITSID_UNLABELED;
 
 	if (sp) {
-- 
2.30.2