Add __xfrm_state_lookup_exact(); wire it into DELSA/GETSA, GETAE/NEWAE,
EXPIRE, MIGRATE_STATE.  xfrm_state_update() (UPDSA) keeps wildcard match
because ALLOCSPI's larval state may be unmarked (mark 0/0), so an
exact-match UPDSA would not find it and the ADD fallback would then
fail with -EEXIST via xfrm_state_add().

Fixes: 3d6acfa7641f ("xfrm: SA lookups with mark")
Signed-off-by: Antony Antony <antony.antony@secunet.com>
---
v2->v3: exact lookup compares the mark value only, no mask; fix typo
v1->v2: UPDSA keep the wildcard lookup
---
 include/net/xfrm.h    |  3 +++
 net/xfrm/xfrm_state.c | 56 ++++++++++++++++++++++++++++++++++++++++++---------
 net/xfrm/xfrm_user.c  | 29 +++++++++++++-------------
 3 files changed, 64 insertions(+), 24 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index a6d69aaa6cd2..9e053388aa4b 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1748,6 +1748,9 @@ struct xfrm_state *xfrm_state_lookup_byaddr(struct net *net, u32 mark,
 					    const xfrm_address_t *saddr,
 					    u8 proto,
 					    unsigned short family);
+struct xfrm_state *xfrm_state_lookup_exact(struct net *net, const struct xfrm_mark *mark,
+					   const xfrm_address_t *daddr, __be32 spi,
+					   u8 proto, unsigned short family);
 #ifdef CONFIG_XFRM_SUB_POLICY
 void xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n,
 		    unsigned short family);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 602404ffc4d4..f1e04df8d501 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1177,11 +1177,19 @@ static struct xfrm_state *__xfrm_state_lookup_all(const struct xfrm_hash_state_p
 	return NULL;
 }
 
-static struct xfrm_state *__xfrm_state_lookup(const struct xfrm_hash_state_ptrs *state_ptrs,
-					      u32 mark,
-					      const xfrm_address_t *daddr,
-					      __be32 spi, u8 proto,
-					      unsigned short family)
+static bool xfrm_state_mark_matches(const struct xfrm_state *x, u32 mark, u32 mask, bool exact)
+{
+	if (exact)
+		return x->mark.v == mark && x->mark.m == mask;
+	return (mark & x->mark.m) == x->mark.v;
+}
+
+static struct xfrm_state *
+__xfrm_state_lookup(const struct xfrm_hash_state_ptrs *state_ptrs,
+		    u32 mark, u32 mask, bool exact,
+		    const xfrm_address_t *daddr,
+		    __be32 spi, u8 proto,
+		    unsigned short family)
 {
 	unsigned int h = __xfrm_spi_hash(daddr, spi, proto, family, state_ptrs->hmask);
 	struct xfrm_state *x;
@@ -1193,7 +1201,7 @@ static struct xfrm_state *__xfrm_state_lookup(const struct xfrm_hash_state_ptrs
 		    !xfrm_addr_equal(&x->id.daddr, daddr, family))
 			continue;
 
-		if ((mark & x->mark.m) != x->mark.v)
+		if (!xfrm_state_mark_matches(x, mark, mask, exact))
 			continue;
 		if (!xfrm_state_hold_rcu(x))
 			continue;
@@ -1203,6 +1211,17 @@ static struct xfrm_state *__xfrm_state_lookup(const struct xfrm_hash_state_ptrs
 	return NULL;
 }
 
+static struct xfrm_state *
+__xfrm_state_lookup_exact(const struct xfrm_hash_state_ptrs *state_ptrs,
+			  const struct xfrm_mark *mark,
+			  const xfrm_address_t *daddr,
+			  __be32 spi, u8 proto,
+			  unsigned short family)
+{
+	return __xfrm_state_lookup(state_ptrs, mark->v, mark->m, true,
+				   daddr, spi, proto, family);
+}
+
 struct xfrm_state *xfrm_input_state_lookup(struct net *net, u32 mark,
 					   const xfrm_address_t *daddr,
 					   __be32 spi, u8 proto,
@@ -1233,7 +1252,7 @@ struct xfrm_state *xfrm_input_state_lookup(struct net *net, u32 mark,
 
 	xfrm_hash_ptrs_get(net, &state_ptrs);
 
-	x = __xfrm_state_lookup(&state_ptrs, mark, daddr, spi, proto, family);
+	x = __xfrm_state_lookup(&state_ptrs, mark, 0, false, daddr, spi, proto, family);
 	if (x) {
 		spin_lock(&net->xfrm.xfrm_state_lock);
 		if (x->km.state != XFRM_STATE_VALID) {
@@ -1283,7 +1302,7 @@ static struct xfrm_state *__xfrm_state_lookup_byaddr(const struct xfrm_hash_stat
 	return NULL;
 }
 
-static inline struct xfrm_state *
+static struct xfrm_state *
 __xfrm_state_locate(struct xfrm_state *x, int use_spi, int family)
 {
 	struct xfrm_hash_state_ptrs state_ptrs;
@@ -1293,7 +1312,7 @@ __xfrm_state_locate(struct xfrm_state *x, int use_spi, int family)
 	xfrm_hash_ptrs_get(net, &state_ptrs);
 
 	if (use_spi)
-		return __xfrm_state_lookup(&state_ptrs, mark, &x->id.daddr,
+		return __xfrm_state_lookup(&state_ptrs, mark, 0, false, &x->id.daddr,
 					   x->id.spi, x->id.proto, family);
 	else
 		return __xfrm_state_lookup_byaddr(&state_ptrs, mark,
@@ -2380,7 +2399,7 @@ xfrm_state_lookup(struct net *net, u32 mark, const xfrm_address_t *daddr, __be32
 	rcu_read_lock();
 	xfrm_hash_ptrs_get(net, &state_ptrs);
 
-	x = __xfrm_state_lookup(&state_ptrs, mark, daddr, spi, proto, family);
+	x = __xfrm_state_lookup(&state_ptrs, mark, 0, false, daddr, spi, proto, family);
 	rcu_read_unlock();
 	return x;
 }
@@ -2404,6 +2423,23 @@ xfrm_state_lookup_byaddr(struct net *net, u32 mark,
 }
 EXPORT_SYMBOL(xfrm_state_lookup_byaddr);
 
+struct xfrm_state *
+xfrm_state_lookup_exact(struct net *net, const struct xfrm_mark *mark,
+			const xfrm_address_t *daddr, __be32 spi,
+			u8 proto, unsigned short family)
+{
+	struct xfrm_hash_state_ptrs state_ptrs;
+	struct xfrm_state *x;
+
+	rcu_read_lock();
+	xfrm_hash_ptrs_get(net, &state_ptrs);
+
+	x = __xfrm_state_lookup_exact(&state_ptrs, mark, daddr, spi, proto, family);
+	rcu_read_unlock();
+	return x;
+}
+EXPORT_SYMBOL(xfrm_state_lookup_exact);
+
 struct xfrm_state *
 xfrm_find_acq(struct net *net, const struct xfrm_mark *mark, u8 mode, u32 reqid,
 	      u32 if_id, u32 pcpu_num, u8 proto, const xfrm_address_t *daddr,
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index c1571c7a2315..5a9f729b4fcb 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1109,11 +1109,12 @@ static struct xfrm_state *xfrm_user_state_lookup(struct net *net,
 	struct xfrm_state *x = NULL;
 	struct xfrm_mark m;
 	int err;
-	u32 mark = xfrm_mark_get(attrs, &m);
+
+	xfrm_mark_get(attrs, &m);
 
 	if (xfrm_id_proto_match(p->proto, IPSEC_PROTO_ANY)) {
 		err = -ESRCH;
-		x = xfrm_state_lookup(net, mark, &p->daddr, p->spi, p->proto, p->family);
+		x = xfrm_state_lookup_exact(net, &m, &p->daddr, p->spi, p->proto, p->family);
 	} else {
 		xfrm_address_t *saddr = NULL;
 
@@ -1124,7 +1125,7 @@ static struct xfrm_state *xfrm_user_state_lookup(struct net *net,
 		}
 
 		err = -ESRCH;
-		x = xfrm_state_lookup_byaddr(net, mark,
+		x = xfrm_state_lookup_byaddr(net, m.v & m.m,
 					     &p->daddr, saddr,
 					     p->proto, p->family);
 	}
@@ -2821,14 +2822,13 @@ static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct sk_buff *r_skb;
 	int err;
 	struct km_event c;
-	u32 mark;
 	struct xfrm_mark m;
 	struct xfrm_aevent_id *p = nlmsg_data(nlh);
 	struct xfrm_usersa_id *id = &p->sa_id;
 
-	mark = xfrm_mark_get(attrs, &m);
+	xfrm_mark_get(attrs, &m);
 
-	x = xfrm_state_lookup(net, mark, &id->daddr, id->spi, id->proto, id->family);
+	x = xfrm_state_lookup_exact(net, &m, &id->daddr, id->spi, id->proto, id->family);
 	if (x == NULL)
 		return -ESRCH;
 
@@ -2869,7 +2869,6 @@ static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct xfrm_state *x;
 	struct km_event c;
 	int err = -EINVAL;
-	u32 mark = 0;
 	struct xfrm_mark m;
 	struct xfrm_aevent_id *p = nlmsg_data(nlh);
 	struct nlattr *rp = attrs[XFRMA_REPLAY_VAL];
@@ -2889,9 +2888,10 @@ static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return err;
 	}
 
-	mark = xfrm_mark_get(attrs, &m);
+	xfrm_mark_get(attrs, &m);
 
-	x = xfrm_state_lookup(net, mark, &p->sa_id.daddr, p->sa_id.spi, p->sa_id.proto, p->sa_id.family);
+	x = xfrm_state_lookup_exact(net, &m, &p->sa_id.daddr, p->sa_id.spi,
+				    p->sa_id.proto, p->sa_id.family);
 	if (x == NULL)
 		return -ESRCH;
 
@@ -3025,9 +3025,10 @@ static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct xfrm_user_expire *ue = nlmsg_data(nlh);
 	struct xfrm_usersa_info *p = &ue->state;
 	struct xfrm_mark m;
-	u32 mark = xfrm_mark_get(attrs, &m);
 
-	x = xfrm_state_lookup(net, mark, &p->id.daddr, p->id.spi, p->id.proto, p->family);
+	xfrm_mark_get(attrs, &m);
+
+	x = xfrm_state_lookup_exact(net, &m, &p->id.daddr, p->id.spi, p->id.proto, p->family);
 
 	err = -ENOENT;
 	if (x == NULL)
@@ -3402,9 +3403,9 @@ static int xfrm_do_migrate_state(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	copy_from_user_migrate_state(&m, um);
 
-	x = xfrm_state_lookup(net, m.old_mark.v & m.old_mark.m,
-			      &um->id.daddr, um->id.spi,
-			      um->id.proto, um->id.family);
+	x = xfrm_state_lookup_exact(net, &m.old_mark,
+				    &um->id.daddr, um->id.spi,
+				    um->id.proto, um->id.family);
 	if (!x) {
 		NL_SET_ERR_MSG(extack, "Can not find state");
 		return -ESRCH;

-- 
2.47.3