diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index c412dde4d67dc..83b8070d1cc93 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -485,6 +485,7 @@ int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
 		 struct fib6_config *cfg, gfp_t gfp_flags,
 		 struct netlink_ext_ack *extack);
 void fib6_nh_release(struct fib6_nh *fib6_nh);
+void fib6_nh_release_dsts(struct fib6_nh *fib6_nh);
 
 int call_fib6_entry_notifiers(struct net *net,
 			      enum fib_event_type event_type,
diff --git a/include/net/ipv6_stubs.h b/include/net/ipv6_stubs.h
index afbce90c44808..45e0339be6fa4 100644
--- a/include/net/ipv6_stubs.h
+++ b/include/net/ipv6_stubs.h
@@ -47,6 +47,7 @@ struct ipv6_stub {
 			    struct fib6_config *cfg, gfp_t gfp_flags,
 			    struct netlink_ext_ack *extack);
 	void (*fib6_nh_release)(struct fib6_nh *fib6_nh);
+	void (*fib6_nh_release_dsts)(struct fib6_nh *fib6_nh);
 	void (*fib6_update_sernum)(struct net *net, struct fib6_info *rt);
 	int (*ip6_del_rt)(struct net *net, struct fib6_info *rt, bool skip_notify);
 	void (*fib6_rt_update)(struct net *net, struct fib6_info *rt,
diff --git a/net/ipv4/nexthop.c b/net/ipv4/nexthop.c
index 9e8100728d464..a69a9e76f99fe 100644
--- a/net/ipv4/nexthop.c
+++ b/net/ipv4/nexthop.c
@@ -1899,15 +1899,36 @@ static void remove_nexthop(struct net *net, struct nexthop *nh,
 /* if any FIB entries reference this nexthop, any dst entries
  * need to be regenerated
  */
-static void nh_rt_cache_flush(struct net *net, struct nexthop *nh)
+static void nh_rt_cache_flush(struct net *net, struct nexthop *nh,
+			      struct nexthop *replaced_nh)
 {
 	struct fib6_info *f6i;
+	struct nh_group *nhg;
+	int i;
 
 	if (!list_empty(&nh->fi_list))
 		rt_cache_flush(net);
 
 	list_for_each_entry(f6i, &nh->f6i_list, nh_list)
 		ipv6_stub->fib6_update_sernum(net, f6i);
+
+	/* if an IPv6 group was replaced, we have to release all old
+	 * dsts to make sure all refcounts are released
+	 */
+	if (!replaced_nh->is_group)
+		return;
+
+	/* new dsts must use only the new nexthop group */
+	synchronize_net();
+
+	nhg = rtnl_dereference(replaced_nh->nh_grp);
+	for (i = 0; i < nhg->num_nh; i++) {
+		struct nh_grp_entry *nhge = &nhg->nh_entries[i];
+		struct nh_info *nhi = rtnl_dereference(nhge->nh->nh_info);
+
+		if (nhi->family == AF_INET6)
+			ipv6_stub->fib6_nh_release_dsts(&nhi->fib6_nh);
+	}
 }
 
 static int replace_nexthop_grp(struct net *net, struct nexthop *old,
@@ -2247,7 +2268,7 @@ static int replace_nexthop(struct net *net, struct nexthop *old,
 		err = replace_nexthop_single(net, old, new, extack);
 
 	if (!err) {
-		nh_rt_cache_flush(net, old);
+		nh_rt_cache_flush(net, old, new);
 
 		__remove_nexthop(net, new, NULL);
 		nexthop_put(new);
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 0c4da163535ad..dab4a047590b7 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -1026,6 +1026,7 @@ static const struct ipv6_stub ipv6_stub_impl = {
 	.ip6_mtu_from_fib6 = ip6_mtu_from_fib6,
 	.fib6_nh_init	   = fib6_nh_init,
 	.fib6_nh_release   = fib6_nh_release,
+	.fib6_nh_release_dsts = fib6_nh_release_dsts,
 	.fib6_update_sernum = fib6_update_sernum_stub,
 	.fib6_rt_update	   = fib6_rt_update,
 	.ip6_del_rt	   = ip6_del_rt,
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 3ae25b8ffbd6f..42d60c76d30a0 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -3680,6 +3680,25 @@ void fib6_nh_release(struct fib6_nh *fib6_nh)
 	fib_nh_common_release(&fib6_nh->nh_common);
 }
 
+void fib6_nh_release_dsts(struct fib6_nh *fib6_nh)
+{
+	int cpu;
+
+	if (!fib6_nh->rt6i_pcpu)
+		return;
+
+	for_each_possible_cpu(cpu) {
+		struct rt6_info *pcpu_rt, **ppcpu_rt;
+
+		ppcpu_rt = per_cpu_ptr(fib6_nh->rt6i_pcpu, cpu);
+		pcpu_rt = xchg(ppcpu_rt, NULL);
+		if (pcpu_rt) {
+			dst_dev_put(&pcpu_rt->dst);
+			dst_release(&pcpu_rt->dst);
+		}
+	}
+}
+
 static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
 					      gfp_t gfp_flags,
 					      struct netlink_ext_ack *extack)
diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh
index b5a69ad191b07..d444ee6aa3cb0 100755
--- a/tools/testing/selftests/net/fib_nexthops.sh
+++ b/tools/testing/selftests/net/fib_nexthops.sh
@@ -629,6 +629,66 @@ ipv6_fcnal()
 	log_test $? 0 "Nexthops removed on admin down"
 }
 
+ipv6_grp_refs()
+{
+	if [ ! -x "$(command -v mausezahn)" ]; then
+		echo "SKIP: Could not run test; need mausezahn tool"
+		return
+	fi
+
+	run_cmd "$IP link set dev veth1 up"
+	run_cmd "$IP link add veth1.10 link veth1 up type vlan id 10"
+	run_cmd "$IP link add veth1.20 link veth1 up type vlan id 20"
+	run_cmd "$IP -6 addr add 2001:db8:91::1/64 dev veth1.10"
+	run_cmd "$IP -6 addr add 2001:db8:92::1/64 dev veth1.20"
+	run_cmd "$IP -6 neigh add 2001:db8:91::2 lladdr 00:11:22:33:44:55 dev veth1.10"
+	run_cmd "$IP -6 neigh add 2001:db8:92::2 lladdr 00:11:22:33:44:55 dev veth1.20"
+	run_cmd "$IP nexthop add id 100 via 2001:db8:91::2 dev veth1.10"
+	run_cmd "$IP nexthop add id 101 via 2001:db8:92::2 dev veth1.20"
+	run_cmd "$IP nexthop add id 102 group 100"
+	run_cmd "$IP route add 2001:db8:101::1/128 nhid 102"
+
+	# create per-cpu dsts through nh 100
+	run_cmd "ip netns exec me mausezahn -6 veth1.10 -B 2001:db8:101::1 -A 2001:db8:91::1 -c 5 -t tcp "dp=1-1023, flags=syn" >/dev/null 2>&1"
+
+	# remove nh 100 from the group to delete the route potentially leaving
+	# a stale per-cpu dst which holds a reference to the nexthop's net
+	# device and to the IPv6 route
+	run_cmd "$IP nexthop replace id 102 group 101"
+	run_cmd "$IP route del 2001:db8:101::1/128"
+
+	# add both nexthops to the group so a reference is taken on them
+	run_cmd "$IP nexthop replace id 102 group 100/101"
+
+	# if the bug described in commit "net: nexthop: release IPv6 per-cpu
+	# dsts when replacing a nexthop group" exists at this point we have
+	# an unlinked IPv6 route (but not freed due to stale dst) with a
+	# reference over the group so we delete the group which will again
+	# only unlink it due to the route reference
+	run_cmd "$IP nexthop del id 102"
+
+	# delete the nexthop with stale dst, since we have an unlinked
+	# group with a ref to it and an unlinked IPv6 route with ref to the
+	# group, the nh will only be unlinked and not freed so the stale dst
+	# remains forever and we get a net device refcount imbalance
+	run_cmd "$IP nexthop del id 100"
+
+	# if a reference was lost this command will hang because the net device
+	# cannot be removed
+	timeout -s KILL 5 ip netns exec me ip link del veth1.10 >/dev/null 2>&1
+
+	# we can't cleanup if the command is hung trying to delete the netdev
+	if [ $? -eq 137 ]; then
+		return 1
+	fi
+
+	# cleanup
+	run_cmd "$IP link del veth1.20"
+	run_cmd "$IP nexthop flush"
+
+	return 0
+}
+
 ipv6_grp_fcnal()
 {
 	local rc
@@ -734,6 +794,9 @@ ipv6_grp_fcnal()
 
 	run_cmd "$IP nexthop add id 108 group 31/24"
 	log_test $? 2 "Nexthop group can not have a blackhole and another nexthop"
+
+	ipv6_grp_refs
+	log_test $? 0 "Nexthop group replace refcounts"
 }
 
 ipv6_res_grp_fcnal()