Merge tag 'ipsec-2026-04-08' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2026-04-08

1) Clear trailing padding in build_polexpire() to prevent
   leaking unititialized memory. From Yasuaki Torimaru.

2) Fix aevent size calculation when XFRMA_IF_ID is used.
   From Keenan Dong.

3) Wait for RCU readers during policy netns exit before
   freeing the policy hash tables.

4) Fix dome too eaerly dropped references on the netdev
   when uding transport mode. From Qi Tang.

5) Fix refcount leak in xfrm_migrate_policy_find().
   From Kotlyarov Mihail.

6) Fix two fix info leaks in build_report() and
   in build_mapping(). From Greg Kroah-Hartman.

7) Zero aligned sockaddr tail in PF_KEY exports.
   From Zhengchuan Liang.

* tag 'ipsec-2026-04-08' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec:
  net: af_key: zero aligned sockaddr tail in PF_KEY exports
  xfrm_user: fix info leak in build_report()
  xfrm_user: fix info leak in build_mapping()
  xfrm: fix refcount leak in xfrm_migrate_policy_find
  xfrm: hold dev ref until after transport_finish NF_HOOK
  xfrm: Wait for RCU readers during policy netns exit
  xfrm: account XFRMA_IF_ID in aevent size calculation
  xfrm: clear trailing padding in build_polexpire()
====================

Link: https://patch.msgid.link/20260408095925.253681-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

6 files changed, 70 insertions, 29 deletions

diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index f28cfd88eaf5..c2eac844bcdb 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -50,6 +50,7 @@ int xfrm4_transport_finish(struct sk_buff *skb, int async)
 {
 	struct xfrm_offload *xo = xfrm_offload(skb);
 	struct iphdr *iph = ip_hdr(skb);
+	struct net_device *dev = skb->dev;
 
 	iph->protocol = XFRM_MODE_SKB_CB(skb)->protocol;
 
@@ -73,8 +74,10 @@ int xfrm4_transport_finish(struct sk_buff *skb, int async)
 	}
 
 	NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING,
-		dev_net(skb->dev), NULL, skb, skb->dev, NULL,
+		dev_net(dev), NULL, skb, dev, NULL,
 		xfrm4_rcv_encap_finish);
+	if (async)
+		dev_put(dev);
 	return 0;
 }
 
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 9005fc156a20..699a001ac166 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -43,6 +43,7 @@ static int xfrm6_transport_finish2(struct net *net, struct sock *sk,
 int xfrm6_transport_finish(struct sk_buff *skb, int async)
 {
 	struct xfrm_offload *xo = xfrm_offload(skb);
+	struct net_device *dev = skb->dev;
 	int nhlen = -skb_network_offset(skb);
 
 	skb_network_header(skb)[IP6CB(skb)->nhoff] =
@@ -68,8 +69,10 @@ int xfrm6_transport_finish(struct sk_buff *skb, int async)
 	}
 
 	NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
-		dev_net(skb->dev), NULL, skb, skb->dev, NULL,
+		dev_net(dev), NULL, skb, dev, NULL,
 		xfrm6_transport_finish2);
+	if (async)
+		dev_put(dev);
 	return 0;
 }
 
diff --git a/net/key/af_key.c b/net/key/af_key.c
index 72ac2ace419d..5d480ae39405 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -757,6 +757,22 @@ static unsigned int pfkey_sockaddr_fill(const xfrm_address_t *xaddr, __be16 port
 	return 0;
 }
 
+static unsigned int pfkey_sockaddr_fill_zero_tail(const xfrm_address_t *xaddr,
+						  __be16 port,
+						  struct sockaddr *sa,
+						  unsigned short family)
+{
+	unsigned int prefixlen;
+	int sockaddr_len = pfkey_sockaddr_len(family);
+	int sockaddr_size = pfkey_sockaddr_size(family);
+
+	prefixlen = pfkey_sockaddr_fill(xaddr, port, sa, family);
+	if (sockaddr_size > sockaddr_len)
+		memset((u8 *)sa + sockaddr_len, 0, sockaddr_size - sockaddr_len);
+
+	return prefixlen;
+}
+
 static struct sk_buff *__pfkey_xfrm_state2msg(const struct xfrm_state *x,
 					      int add_keys, int hsc)
 {
@@ -3206,9 +3222,9 @@ static int pfkey_send_acquire(struct xfrm_state *x, struct xfrm_tmpl *t, struct
 	addr->sadb_address_proto = 0;
 	addr->sadb_address_reserved = 0;
 	addr->sadb_address_prefixlen =
-		pfkey_sockaddr_fill(&x->props.saddr, 0,
-				    (struct sockaddr *) (addr + 1),
-				    x->props.family);
+		pfkey_sockaddr_fill_zero_tail(&x->props.saddr, 0,
+					      (struct sockaddr *)(addr + 1),
+					      x->props.family);
 	if (!addr->sadb_address_prefixlen)
 		BUG();
 
@@ -3221,9 +3237,9 @@ static int pfkey_send_acquire(struct xfrm_state *x, struct xfrm_tmpl *t, struct
 	addr->sadb_address_proto = 0;
 	addr->sadb_address_reserved = 0;
 	addr->sadb_address_prefixlen =
-		pfkey_sockaddr_fill(&x->id.daddr, 0,
-				    (struct sockaddr *) (addr + 1),
-				    x->props.family);
+		pfkey_sockaddr_fill_zero_tail(&x->id.daddr, 0,
+					      (struct sockaddr *)(addr + 1),
+					      x->props.family);
 	if (!addr->sadb_address_prefixlen)
 		BUG();
 
@@ -3421,9 +3437,9 @@ static int pfkey_send_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr,
 	addr->sadb_address_proto = 0;
 	addr->sadb_address_reserved = 0;
 	addr->sadb_address_prefixlen =
-		pfkey_sockaddr_fill(&x->props.saddr, 0,
-				    (struct sockaddr *) (addr + 1),
-				    x->props.family);
+		pfkey_sockaddr_fill_zero_tail(&x->props.saddr, 0,
+					      (struct sockaddr *)(addr + 1),
+					      x->props.family);
 	if (!addr->sadb_address_prefixlen)
 		BUG();
 
@@ -3443,9 +3459,9 @@ static int pfkey_send_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr,
 	addr->sadb_address_proto = 0;
 	addr->sadb_address_reserved = 0;
 	addr->sadb_address_prefixlen =
-		pfkey_sockaddr_fill(ipaddr, 0,
-				    (struct sockaddr *) (addr + 1),
-				    x->props.family);
+		pfkey_sockaddr_fill_zero_tail(ipaddr, 0,
+					      (struct sockaddr *)(addr + 1),
+					      x->props.family);
 	if (!addr->sadb_address_prefixlen)
 		BUG();
 
@@ -3474,15 +3490,15 @@ static int set_sadb_address(struct sk_buff *skb, int sasize, int type,
 	switch (type) {
 	case SADB_EXT_ADDRESS_SRC:
 		addr->sadb_address_prefixlen = sel->prefixlen_s;
-		pfkey_sockaddr_fill(&sel->saddr, 0,
-				    (struct sockaddr *)(addr + 1),
-				    sel->family);
+		pfkey_sockaddr_fill_zero_tail(&sel->saddr, 0,
+					      (struct sockaddr *)(addr + 1),
+					      sel->family);
 		break;
 	case SADB_EXT_ADDRESS_DST:
 		addr->sadb_address_prefixlen = sel->prefixlen_d;
-		pfkey_sockaddr_fill(&sel->daddr, 0,
-				    (struct sockaddr *)(addr + 1),
-				    sel->family);
+		pfkey_sockaddr_fill_zero_tail(&sel->daddr, 0,
+					      (struct sockaddr *)(addr + 1),
+					      sel->family);
 		break;
 	default:
 		return -EINVAL;
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index dc1312ed5a09..f65291eba1f6 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -506,7 +506,6 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 		/* An encap_type of -1 indicates async resumption. */
 		if (encap_type == -1) {
 			async = 1;
-			dev_put(skb->dev);
 			seq = XFRM_SKB_CB(skb)->seq.input.low;
 			spin_lock(&x->lock);
 			goto resume;
@@ -659,8 +658,11 @@ process:
 			dev_hold(skb->dev);
 
 			nexthdr = x->type->input(x, skb);
-			if (nexthdr == -EINPROGRESS)
+			if (nexthdr == -EINPROGRESS) {
+				if (async)
+					dev_put(skb->dev);
 				return 0;
+			}
 
 			dev_put(skb->dev);
 			spin_lock(&x->lock);
@@ -695,9 +697,11 @@ resume:
 		XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 
 		err = xfrm_inner_mode_input(x, skb);
-		if (err == -EINPROGRESS)
+		if (err == -EINPROGRESS) {
+			if (async)
+				dev_put(skb->dev);
 			return 0;
-		else if (err) {
+		} else if (err) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 			goto drop;
 		}
@@ -734,6 +738,8 @@ resume_decapped:
 			sp->olen = 0;
 		if (skb_valid_dst(skb))
 			skb_dst_drop(skb);
+		if (async)
+			dev_put(skb->dev);
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
 	} else {
@@ -753,6 +759,8 @@ resume_decapped:
 				sp->olen = 0;
 			if (skb_valid_dst(skb))
 				skb_dst_drop(skb);
+			if (async)
+				dev_put(skb->dev);
 			gro_cells_receive(&gro_cells, skb);
 			return err;
 		}
@@ -763,6 +771,8 @@ resume_decapped:
 drop_unlock:
 	spin_unlock(&x->lock);
 drop:
+	if (async)
+		dev_put(skb->dev);
 	xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
 	kfree_skb(skb);
 	return 0;
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 362939aa56cf..a872af5610dc 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -4290,6 +4290,8 @@ static void xfrm_policy_fini(struct net *net)
 #endif
 	xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
 
+	synchronize_rcu();
+
 	WARN_ON(!list_empty(&net->xfrm.policy_all));
 
 	for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
@@ -4526,9 +4528,6 @@ static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *
 	pol = xfrm_policy_lookup_bytype(net, type, &fl, sel->family, dir, if_id);
 	if (IS_ERR_OR_NULL(pol))
 		goto out_unlock;
-
-	if (!xfrm_pol_hold_rcu(pol))
-		pol = NULL;
 out_unlock:
 	rcu_read_unlock();
 	return pol;
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 1656b487f833..d56450f61669 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2677,7 +2677,8 @@ static inline unsigned int xfrm_aevent_msgsize(struct xfrm_state *x)
 	       + nla_total_size(4) /* XFRM_AE_RTHR */
 	       + nla_total_size(4) /* XFRM_AE_ETHR */
 	       + nla_total_size(sizeof(x->dir)) /* XFRMA_SA_DIR */
-	       + nla_total_size(4); /* XFRMA_SA_PCPU */
+	       + nla_total_size(4) /* XFRMA_SA_PCPU */
+	       + nla_total_size(sizeof(x->if_id)); /* XFRMA_IF_ID */
 }
 
 static int build_aevent(struct sk_buff *skb, struct xfrm_state *x, const struct km_event *c)
@@ -2789,7 +2790,12 @@ static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
 	c.portid = nlh->nlmsg_pid;
 
 	err = build_aevent(r_skb, x, &c);
-	BUG_ON(err < 0);
+	if (err < 0) {
+		spin_unlock_bh(&x->lock);
+		xfrm_state_put(x);
+		kfree_skb(r_skb);
+		return err;
+	}
 
 	err = nlmsg_unicast(xfrm_net_nlsk(net, skb), r_skb, NETLINK_CB(skb).portid);
 	spin_unlock_bh(&x->lock);
@@ -3960,6 +3966,8 @@ static int build_polexpire(struct sk_buff *skb, struct xfrm_policy *xp,
 		return err;
 	}
 	upe->hard = !!hard;
+	/* clear the padding bytes */
+	memset_after(upe, 0, hard);
 
 	nlmsg_end(skb, nlh);
 	return 0;
@@ -4117,6 +4125,7 @@ static int build_report(struct sk_buff *skb, u8 proto,
 		return -EMSGSIZE;
 
 	ur = nlmsg_data(nlh);
+	memset(ur, 0, sizeof(*ur));
 	ur->proto = proto;
 	memcpy(&ur->sel, sel, sizeof(ur->sel));
 
@@ -4164,6 +4173,7 @@ static int build_mapping(struct sk_buff *skb, struct xfrm_state *x,
 
 	um = nlmsg_data(nlh);
 
+	memset(&um->id, 0, sizeof(um->id));
 	memcpy(&um->id.daddr, &x->id.daddr, sizeof(um->id.daddr));
 	um->id.spi = x->id.spi;
 	um->id.family = x->props.family;