diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst
index b882d4238581..04216564a03c 100644
--- a/Documentation/networking/ip-sysctl.rst
+++ b/Documentation/networking/ip-sysctl.rst
@@ -2474,21 +2474,16 @@ drop_unsolicited_na - BOOLEAN
 
 	By default this is turned off.
 
-accept_unsolicited_na - BOOLEAN
-	Add a new neighbour cache entry in STALE state for routers on receiving an
-	unsolicited neighbour advertisement with target link-layer address option
-	specified. This is as per router-side behavior documented in RFC9131.
-	This has lower precedence than drop_unsolicited_na.
+accept_untracked_na - BOOLEAN
+	Add a new neighbour cache entry in STALE state for routers on receiving a
+	neighbour advertisement (either solicited or unsolicited) with target
+	link-layer address option specified if no neighbour entry is already
+	present for the advertised IPv6 address. Without this knob, NAs received
+	for untracked addresses (absent in neighbour cache) are silently ignored.
 
-	 ====   ======  ======  ==============================================
-	 drop   accept  fwding                   behaviour
-	 ----   ------  ------  ----------------------------------------------
-	    1        X       X  Drop NA packet and don't pass up the stack
-	    0        0       X  Pass NA packet up the stack, don't update NC
-	    0        1       0  Pass NA packet up the stack, don't update NC
-	    0        1       1  Pass NA packet up the stack, and add a STALE
-	                        NC entry
-	 ====   ======  ======  ==============================================
+	This is as per router-side behaviour documented in RFC9131.
+
+	This has lower precedence than drop_unsolicited_na.
 
 	This will optimize the return path for the initial off-link communication
 	that is initiated by a directly connected host, by ensuring that
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 38c8203d52cb..37dfdcfcdd54 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -61,7 +61,7 @@ struct ipv6_devconf {
 	__s32		suppress_frag_ndisc;
 	__s32		accept_ra_mtu;
 	__s32		drop_unsolicited_na;
-	__s32		accept_unsolicited_na;
+	__s32		accept_untracked_na;
 	struct ipv6_stable_secret {
 		bool initialized;
 		struct in6_addr secret;
diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
index 549ddeaf788b..03cdbe798fe3 100644
--- a/include/uapi/linux/ipv6.h
+++ b/include/uapi/linux/ipv6.h
@@ -194,7 +194,7 @@ enum {
 	DEVCONF_IOAM6_ID,
 	DEVCONF_IOAM6_ID_WIDE,
 	DEVCONF_NDISC_EVICT_NOCARRIER,
-	DEVCONF_ACCEPT_UNSOLICITED_NA,
+	DEVCONF_ACCEPT_UNTRACKED_NA,
 	DEVCONF_MAX
 };
 
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index ca0aa744593e..1b1932502e9e 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5586,7 +5586,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
 	array[DEVCONF_IOAM6_ID] = cnf->ioam6_id;
 	array[DEVCONF_IOAM6_ID_WIDE] = cnf->ioam6_id_wide;
 	array[DEVCONF_NDISC_EVICT_NOCARRIER] = cnf->ndisc_evict_nocarrier;
-	array[DEVCONF_ACCEPT_UNSOLICITED_NA] = cnf->accept_unsolicited_na;
+	array[DEVCONF_ACCEPT_UNTRACKED_NA] = cnf->accept_untracked_na;
 }
 
 static inline size_t inet6_ifla6_size(void)
@@ -7038,8 +7038,8 @@ static const struct ctl_table addrconf_sysctl[] = {
 		.extra2		= (void *)SYSCTL_ONE,
 	},
 	{
-		.procname	= "accept_unsolicited_na",
-		.data		= &ipv6_devconf.accept_unsolicited_na,
+		.procname	= "accept_untracked_na",
+		.data		= &ipv6_devconf.accept_untracked_na,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 254addad0dd3..b0dfe97ea4ee 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -979,7 +979,7 @@ static void ndisc_recv_na(struct sk_buff *skb)
 	struct inet6_dev *idev = __in6_dev_get(dev);
 	struct inet6_ifaddr *ifp;
 	struct neighbour *neigh;
-	bool create_neigh;
+	u8 new_state;
 
 	if (skb->len < sizeof(struct nd_msg)) {
 		ND_PRINTK(2, warn, "NA: packet too short\n");
@@ -1000,7 +1000,7 @@ static void ndisc_recv_na(struct sk_buff *skb)
 	/* For some 802.11 wireless deployments (and possibly other networks),
 	 * there will be a NA proxy and unsolicitd packets are attacks
 	 * and thus should not be accepted.
-	 * drop_unsolicited_na takes precedence over accept_unsolicited_na
+	 * drop_unsolicited_na takes precedence over accept_untracked_na
 	 */
 	if (!msg->icmph.icmp6_solicited && idev &&
 	    idev->cnf.drop_unsolicited_na)
@@ -1041,25 +1041,33 @@ static void ndisc_recv_na(struct sk_buff *skb)
 		in6_ifa_put(ifp);
 		return;
 	}
+
+	neigh = neigh_lookup(&nd_tbl, &msg->target, dev);
+
 	/* RFC 9131 updates original Neighbour Discovery RFC 4861.
-	 * An unsolicited NA can now create a neighbour cache entry
-	 * on routers if it has Target LL Address option.
+	 * NAs with Target LL Address option without a corresponding
+	 * entry in the neighbour cache can now create a STALE neighbour
+	 * cache entry on routers.
+	 *
+	 *   entry accept  fwding  solicited        behaviour
+	 * ------- ------  ------  ---------    ----------------------
+	 * present      X       X         0     Set state to STALE
+	 * present      X       X         1     Set state to REACHABLE
+	 *  absent      0       X         X     Do nothing
+	 *  absent      1       0         X     Do nothing
+	 *  absent      1       1         X     Add a new STALE entry
 	 *
-	 * drop   accept  fwding                   behaviour
-	 * ----   ------  ------  ----------------------------------------------
-	 *    1        X       X  Drop NA packet and don't pass up the stack
-	 *    0        0       X  Pass NA packet up the stack, don't update NC
-	 *    0        1       0  Pass NA packet up the stack, don't update NC
-	 *    0        1       1  Pass NA packet up the stack, and add a STALE
-	 *                          NC entry
 	 * Note that we don't do a (daddr == all-routers-mcast) check.
 	 */
-	create_neigh = !msg->icmph.icmp6_solicited && lladdr &&
-		       idev && idev->cnf.forwarding &&
-		       idev->cnf.accept_unsolicited_na;
-	neigh = __neigh_lookup(&nd_tbl, &msg->target, dev, create_neigh);
+	new_state = msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE;
+	if (!neigh && lladdr &&
+	    idev && idev->cnf.forwarding &&
+	    idev->cnf.accept_untracked_na) {
+		neigh = neigh_create(&nd_tbl, &msg->target, dev);
+		new_state = NUD_STALE;
+	}
 
-	if (neigh) {
+	if (neigh && !IS_ERR(neigh)) {
 		u8 old_flags = neigh->flags;
 		struct net *net = dev_net(dev);
 
@@ -1079,7 +1087,7 @@ static void ndisc_recv_na(struct sk_buff *skb)
 		}
 
 		ndisc_update(dev, neigh, lladdr,
-			     msg->icmph.icmp6_solicited ? NUD_REACHABLE : NUD_STALE,
+			     new_state,
 			     NEIGH_UPDATE_F_WEAK_OVERRIDE|
 			     (msg->icmph.icmp6_override ? NEIGH_UPDATE_F_OVERRIDE : 0)|
 			     NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
diff --git a/tools/testing/selftests/net/ndisc_unsolicited_na_test.sh b/tools/testing/selftests/net/ndisc_unsolicited_na_test.sh
index f508657ee126..86e621b7b9c7 100755
--- a/tools/testing/selftests/net/ndisc_unsolicited_na_test.sh
+++ b/tools/testing/selftests/net/ndisc_unsolicited_na_test.sh
@@ -1,15 +1,14 @@
 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 
-# This test is for the accept_unsolicited_na feature to
+# This test is for the accept_untracked_na feature to
 # enable RFC9131 behaviour. The following is the test-matrix.
 # drop   accept  fwding                   behaviour
 # ----   ------  ------  ----------------------------------------------
-#    1        X       X  Drop NA packet and don't pass up the stack
-#    0        0       X  Pass NA packet up the stack, don't update NC
-#    0        1       0  Pass NA packet up the stack, don't update NC
-#    0        1       1  Pass NA packet up the stack, and add a STALE
-#                           NC entry
+#    1        X       X  Don't update NC
+#    0        0       X  Don't update NC
+#    0        1       0  Don't update NC
+#    0        1       1  Add a STALE NC entry
 
 ret=0
 # Kselftest framework requirement - SKIP code is 4.
@@ -72,7 +71,7 @@ setup()
 	set -e
 
 	local drop_unsolicited_na=$1
-	local accept_unsolicited_na=$2
+	local accept_untracked_na=$2
 	local forwarding=$3
 
 	# Setup two namespaces and a veth tunnel across them.
@@ -93,7 +92,7 @@ setup()
 	${IP_ROUTER_EXEC} sysctl -qw \
                 ${ROUTER_CONF}.drop_unsolicited_na=${drop_unsolicited_na}
 	${IP_ROUTER_EXEC} sysctl -qw \
-                ${ROUTER_CONF}.accept_unsolicited_na=${accept_unsolicited_na}
+                ${ROUTER_CONF}.accept_untracked_na=${accept_untracked_na}
 	${IP_ROUTER_EXEC} sysctl -qw ${ROUTER_CONF}.disable_ipv6=0
 	${IP_ROUTER} addr add ${ROUTER_ADDR_WITH_MASK} dev ${ROUTER_INTF}
 
@@ -144,13 +143,13 @@ link_up() {
 
 verify_ndisc() {
 	local drop_unsolicited_na=$1
-	local accept_unsolicited_na=$2
+	local accept_untracked_na=$2
 	local forwarding=$3
 
 	neigh_show_output=$(${IP_ROUTER} neigh show \
                 to ${HOST_ADDR} dev ${ROUTER_INTF} nud stale)
 	if [ ${drop_unsolicited_na} -eq 0 ] && \
-			[ ${accept_unsolicited_na} -eq 1 ] && \
+			[ ${accept_untracked_na} -eq 1 ] && \
 			[ ${forwarding} -eq 1 ]; then
 		# Neighbour entry expected to be present for 011 case
 		[[ ${neigh_show_output} ]]
@@ -179,14 +178,14 @@ test_unsolicited_na_combination() {
 	test_unsolicited_na_common $1 $2 $3
 	test_msg=("test_unsolicited_na: "
 		"drop_unsolicited_na=$1 "
-		"accept_unsolicited_na=$2 "
+		"accept_untracked_na=$2 "
 		"forwarding=$3")
 	log_test $? 0 "${test_msg[*]}"
 	cleanup
 }
 
 test_unsolicited_na_combinations() {
-	# Args: drop_unsolicited_na accept_unsolicited_na forwarding
+	# Args: drop_unsolicited_na accept_untracked_na forwarding
 
 	# Expect entry
 	test_unsolicited_na_combination 0 1 1