[RFC PATCH v1 28/30] sysctl: net: use sysctl_field in IPv6 devconf sysctls

[Alexey Gladkov <legion@kernel.org>]

IPv6 devconf allocates a private sysctl table for each registered
devconf only so registration can rewrite data pointers and attach the
matching inet6_dev and net namespace through extra1 and extra2.

Use sysctl_field with an IPv6 devconf registration context instead. The
table descriptors can stay static and const, while custom handlers still
see the same data, extra1 and extra2 values they used before.

This removes the per-devconf sysctl table clone and the matching
unregister side free.

Signed-off-by: Alexey Gladkov <legion@kernel.org>
---
 net/ipv6/addrconf.c | 746 +++++++++++++++-----------------------------
 1 file changed, 252 insertions(+), 494 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 5476b6536eb7..a3bac460e7bd 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -6826,516 +6826,280 @@ static int addrconf_sysctl_force_forwarding(const struct ctl_table *ctl, int wri
 }
 
 static int minus_one = -1;
-static const int two_five_five = 255;
+static int two_five_five = 255;
 static u32 ioam6_if_id_max = U16_MAX;
 
-static const struct ctl_table addrconf_sysctl[] = {
-	{
-		.procname	= "forwarding",
-		.data		= &ipv6_devconf.forwarding,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_forward,
-	},
-	{
-		.procname	= "hop_limit",
-		.data		= &ipv6_devconf.hop_limit,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= (void *)SYSCTL_ONE,
-		.extra2		= (void *)&two_five_five,
-	},
-	{
-		.procname	= "mtu",
-		.data		= &ipv6_devconf.mtu6,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_mtu,
-	},
-	{
-		.procname	= "accept_ra",
-		.data		= &ipv6_devconf.accept_ra,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "accept_redirects",
-		.data		= &ipv6_devconf.accept_redirects,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "autoconf",
-		.data		= &ipv6_devconf.autoconf,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "dad_transmits",
-		.data		= &ipv6_devconf.dad_transmits,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "router_solicitations",
-		.data		= &ipv6_devconf.rtr_solicits,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= &minus_one,
-	},
-	{
-		.procname	= "router_solicitation_interval",
-		.data		= &ipv6_devconf.rtr_solicit_interval,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_jiffies,
-	},
-	{
-		.procname	= "router_solicitation_max_interval",
-		.data		= &ipv6_devconf.rtr_solicit_max_interval,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_jiffies,
-	},
-	{
-		.procname	= "router_solicitation_delay",
-		.data		= &ipv6_devconf.rtr_solicit_delay,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_jiffies,
-	},
-	{
-		.procname	= "force_mld_version",
-		.data		= &ipv6_devconf.force_mld_version,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "mldv1_unsolicited_report_interval",
-		.data		=
-			&ipv6_devconf.mldv1_unsolicited_report_interval,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_ms_jiffies,
-	},
-	{
-		.procname	= "mldv2_unsolicited_report_interval",
-		.data		=
-			&ipv6_devconf.mldv2_unsolicited_report_interval,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_ms_jiffies,
-	},
-	{
-		.procname	= "use_tempaddr",
-		.data		= &ipv6_devconf.use_tempaddr,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "temp_valid_lft",
-		.data		= &ipv6_devconf.temp_valid_lft,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "temp_prefered_lft",
-		.data		= &ipv6_devconf.temp_prefered_lft,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname       = "regen_min_advance",
-		.data           = &ipv6_devconf.regen_min_advance,
-		.maxlen         = sizeof(int),
-		.mode           = 0644,
-		.proc_handler   = proc_dointvec,
-	},
-	{
-		.procname	= "regen_max_retry",
-		.data		= &ipv6_devconf.regen_max_retry,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "max_desync_factor",
-		.data		= &ipv6_devconf.max_desync_factor,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "max_addresses",
-		.data		= &ipv6_devconf.max_addresses,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "accept_ra_defrtr",
-		.data		= &ipv6_devconf.accept_ra_defrtr,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "ra_defrtr_metric",
-		.data		= &ipv6_devconf.ra_defrtr_metric,
-		.maxlen		= sizeof(u32),
-		.mode		= 0644,
-		.proc_handler	= proc_douintvec_minmax,
-		.extra1		= (void *)SYSCTL_ONE,
-	},
-	{
-		.procname	= "accept_ra_min_hop_limit",
-		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "accept_ra_min_lft",
-		.data		= &ipv6_devconf.accept_ra_min_lft,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "accept_ra_pinfo",
-		.data		= &ipv6_devconf.accept_ra_pinfo,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "ra_honor_pio_life",
-		.data		= &ipv6_devconf.ra_honor_pio_life,
-		.maxlen		= sizeof(u8),
-		.mode		= 0644,
-		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_ONE,
-	},
-	{
-		.procname	= "ra_honor_pio_pflag",
-		.data		= &ipv6_devconf.ra_honor_pio_pflag,
-		.maxlen		= sizeof(u8),
-		.mode		= 0644,
-		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_ONE,
-	},
+struct addrconf_ctl_context {
+	struct sysctl_context context;
+	struct ipv6_devconf *devconf;
+};
+
+#define ADDRCONF_DATA(type, field)						\
+static type *addrconf_ ## field ## _data(const struct sysctl_context *ctx)	\
+{										\
+	const struct addrconf_ctl_context *addrconf_ctx =			\
+		container_of(ctx, struct addrconf_ctl_context, context);	\
+	return &addrconf_ctx->devconf->field;					\
+}
+
+static void *addrconf_idev_data(const struct sysctl_context *ctx)
+{
+	const struct addrconf_ctl_context *addrconf_ctx =
+		container_of(ctx, struct addrconf_ctl_context, context);
+	struct ipv6_devconf *cnf = addrconf_ctx->devconf;
+	struct net *net = ctx->ns.net_ns;
+
+	if (cnf == net->ipv6.devconf_all || cnf == net->ipv6.devconf_dflt)
+		return NULL;
+
+	return container_of(cnf, struct inet6_dev, cnf);
+}
+
+static void *addrconf_net_data(const struct sysctl_context *ctx)
+{
+	return ctx->ns.net_ns;
+}
+
+#define ADDRCONF_CUSTOM_ENTRY(field, name, mval, len, proc)		\
+	{								\
+		.procname	= name,					\
+		.mode		= mval,					\
+		.type		= SYSCTL_FIELD_CUSTOM,			\
+		.ctl_custom	= {					\
+			.proc_handler	= proc,				\
+			.data		= addrconf_ ## field ## _data,	\
+			.extra1		= addrconf_idev_data,		\
+			.extra2		= addrconf_net_data,		\
+			.maxlen		= len,				\
+		},							\
+	}
+
+#define ADDRCONF_INT_ENTRY(field, name) \
+	SYSCTL_FIELD_INT(name, 0644, addrconf_ ## field ## _data)
+
+#define ADDRCONF_INT_RO_ENTRY(field, name) \
+	SYSCTL_FIELD_INT(name, 0444, addrconf_ ## field ## _data)
+
+#define ADDRCONF_INT_MINMAX_ENTRY(field, name, min, max) \
+	SYSCTL_FIELD_STATIC_INT_MINMAX(name, 0644, \
+				       addrconf_ ## field ## _data, min, max)
+
+#define ADDRCONF_UINT_ENTRY(field, name) \
+	SYSCTL_FIELD_UINT(name, 0644, addrconf_ ## field ## _data)
+
+#define ADDRCONF_UINT_MINMAX_ENTRY(field, name, min, max) \
+	SYSCTL_FIELD_STATIC_UINT_MINMAX(name, 0644, \
+				        addrconf_ ## field ## _data, min, max)
+
+#define ADDRCONF_U8_MINMAX_ENTRY(field, name, min, max) \
+	SYSCTL_FIELD_STATIC_U8_MINMAX(name, 0644, \
+				      addrconf_ ## field ## _data, min, max)
+
+ADDRCONF_DATA(void, forwarding)
+ADDRCONF_DATA(int, hop_limit)
+ADDRCONF_DATA(void, mtu6)
+ADDRCONF_DATA(int, accept_ra)
+ADDRCONF_DATA(int, accept_redirects)
+ADDRCONF_DATA(int, autoconf)
+ADDRCONF_DATA(int, dad_transmits)
+ADDRCONF_DATA(int, rtr_solicits)
+ADDRCONF_DATA(void, rtr_solicit_interval)
+ADDRCONF_DATA(void, rtr_solicit_max_interval)
+ADDRCONF_DATA(void, rtr_solicit_delay)
+ADDRCONF_DATA(int, force_mld_version)
+ADDRCONF_DATA(void, mldv1_unsolicited_report_interval)
+ADDRCONF_DATA(void, mldv2_unsolicited_report_interval)
+ADDRCONF_DATA(int, use_tempaddr)
+ADDRCONF_DATA(int, temp_valid_lft)
+ADDRCONF_DATA(int, temp_prefered_lft)
+ADDRCONF_DATA(int, regen_min_advance)
+ADDRCONF_DATA(int, regen_max_retry)
+ADDRCONF_DATA(int, max_desync_factor)
+ADDRCONF_DATA(int, max_addresses)
+ADDRCONF_DATA(int, accept_ra_defrtr)
+ADDRCONF_DATA(unsigned int, ra_defrtr_metric)
+ADDRCONF_DATA(int, accept_ra_min_hop_limit)
+ADDRCONF_DATA(int, accept_ra_min_lft)
+ADDRCONF_DATA(int, accept_ra_pinfo)
+ADDRCONF_DATA(u8, ra_honor_pio_life)
+ADDRCONF_DATA(u8, ra_honor_pio_pflag)
 #ifdef CONFIG_IPV6_ROUTER_PREF
-	{
-		.procname	= "accept_ra_rtr_pref",
-		.data		= &ipv6_devconf.accept_ra_rtr_pref,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "router_probe_interval",
-		.data		= &ipv6_devconf.rtr_probe_interval,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_jiffies,
-	},
+ADDRCONF_DATA(int, accept_ra_rtr_pref)
+ADDRCONF_DATA(void, rtr_probe_interval)
 #ifdef CONFIG_IPV6_ROUTE_INFO
-	{
-		.procname	= "accept_ra_rt_info_min_plen",
-		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "accept_ra_rt_info_max_plen",
-		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
+ADDRCONF_DATA(int, accept_ra_rt_info_min_plen)
+ADDRCONF_DATA(int, accept_ra_rt_info_max_plen)
 #endif
 #endif
-	{
-		.procname	= "proxy_ndp",
-		.data		= &ipv6_devconf.proxy_ndp,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_proxy_ndp,
-	},
-	{
-		.procname	= "accept_source_route",
-		.data		= &ipv6_devconf.accept_source_route,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
+ADDRCONF_DATA(void, proxy_ndp)
+ADDRCONF_DATA(int, accept_source_route)
 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
-	{
-		.procname	= "optimistic_dad",
-		.data		= &ipv6_devconf.optimistic_dad,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler   = proc_dointvec,
-	},
-	{
-		.procname	= "use_optimistic",
-		.data		= &ipv6_devconf.use_optimistic,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
+ADDRCONF_DATA(int, optimistic_dad)
+ADDRCONF_DATA(int, use_optimistic)
 #endif
 #ifdef CONFIG_IPV6_MROUTE
-	{
-		.procname	= "mc_forwarding",
-		.data		= &ipv6_devconf.mc_forwarding,
-		.maxlen		= sizeof(int),
-		.mode		= 0444,
-		.proc_handler	= proc_dointvec,
-	},
+ADDRCONF_DATA(void, mc_forwarding)
 #endif
-	{
-		.procname	= "disable_ipv6",
-		.data		= &ipv6_devconf.disable_ipv6,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_disable,
-	},
-	{
-		.procname	= "accept_dad",
-		.data		= &ipv6_devconf.accept_dad,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "force_tllao",
-		.data		= &ipv6_devconf.force_tllao,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
-	{
-		.procname	= "ndisc_notify",
-		.data		= &ipv6_devconf.ndisc_notify,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
-	{
-		.procname	= "suppress_frag_ndisc",
-		.data		= &ipv6_devconf.suppress_frag_ndisc,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
-	{
-		.procname	= "accept_ra_from_local",
-		.data		= &ipv6_devconf.accept_ra_from_local,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "accept_ra_mtu",
-		.data		= &ipv6_devconf.accept_ra_mtu,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "stable_secret",
-		.data		= &ipv6_devconf.stable_secret,
-		.maxlen		= IPV6_MAX_STRLEN,
-		.mode		= 0600,
-		.proc_handler	= addrconf_sysctl_stable_secret,
-	},
-	{
-		.procname	= "use_oif_addrs_only",
-		.data		= &ipv6_devconf.use_oif_addrs_only,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "ignore_routes_with_linkdown",
-		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
-	},
-	{
-		.procname	= "drop_unicast_in_l2_multicast",
-		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "drop_unsolicited_na",
-		.data		= &ipv6_devconf.drop_unsolicited_na,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-	{
-		.procname	= "keep_addr_on_down",
-		.data		= &ipv6_devconf.keep_addr_on_down,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-
-	},
-	{
-		.procname	= "seg6_enabled",
-		.data		= &ipv6_devconf.seg6_enabled,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
+ADDRCONF_DATA(void, disable_ipv6)
+ADDRCONF_DATA(int, accept_dad)
+ADDRCONF_DATA(int, force_tllao)
+ADDRCONF_DATA(int, ndisc_notify)
+ADDRCONF_DATA(int, suppress_frag_ndisc)
+ADDRCONF_DATA(int, accept_ra_from_local)
+ADDRCONF_DATA(int, accept_ra_mtu)
+ADDRCONF_DATA(void, stable_secret)
+ADDRCONF_DATA(int, use_oif_addrs_only)
+ADDRCONF_DATA(void, ignore_routes_with_linkdown)
+ADDRCONF_DATA(int, drop_unicast_in_l2_multicast)
+ADDRCONF_DATA(int, drop_unsolicited_na)
+ADDRCONF_DATA(int, keep_addr_on_down)
+ADDRCONF_DATA(int, seg6_enabled)
 #ifdef CONFIG_IPV6_SEG6_HMAC
-	{
-		.procname	= "seg6_require_hmac",
-		.data		= &ipv6_devconf.seg6_require_hmac,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
+ADDRCONF_DATA(int, seg6_require_hmac)
 #endif
-	{
-		.procname       = "enhanced_dad",
-		.data           = &ipv6_devconf.enhanced_dad,
-		.maxlen         = sizeof(int),
-		.mode           = 0644,
-		.proc_handler   = proc_dointvec,
-	},
-	{
-		.procname	= "addr_gen_mode",
-		.data		= &ipv6_devconf.addr_gen_mode,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_addr_gen_mode,
-	},
-	{
-		.procname       = "disable_policy",
-		.data           = &ipv6_devconf.disable_policy,
-		.maxlen         = sizeof(int),
-		.mode           = 0644,
-		.proc_handler   = addrconf_sysctl_disable_policy,
-	},
-	{
-		.procname	= "ndisc_tclass",
-		.data		= &ipv6_devconf.ndisc_tclass,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= (void *)SYSCTL_ZERO,
-		.extra2		= (void *)&two_five_five,
-	},
-	{
-		.procname	= "rpl_seg_enabled",
-		.data		= &ipv6_devconf.rpl_seg_enabled,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler   = proc_dointvec_minmax,
-		.extra1         = SYSCTL_ZERO,
-		.extra2         = SYSCTL_ONE,
-	},
-	{
-		.procname	= "ioam6_enabled",
-		.data		= &ipv6_devconf.ioam6_enabled,
-		.maxlen		= sizeof(u8),
-		.mode		= 0644,
-		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= (void *)SYSCTL_ZERO,
-		.extra2		= (void *)SYSCTL_ONE,
-	},
-	{
-		.procname	= "ioam6_id",
-		.data		= &ipv6_devconf.ioam6_id,
-		.maxlen		= sizeof(u32),
-		.mode		= 0644,
-		.proc_handler	= proc_douintvec_minmax,
-		.extra1		= (void *)SYSCTL_ZERO,
-		.extra2		= (void *)&ioam6_if_id_max,
-	},
-	{
-		.procname	= "ioam6_id_wide",
-		.data		= &ipv6_devconf.ioam6_id_wide,
-		.maxlen		= sizeof(u32),
-		.mode		= 0644,
-		.proc_handler	= proc_douintvec,
-	},
-	{
-		.procname	= "ndisc_evict_nocarrier",
-		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
-		.maxlen		= sizeof(u8),
-		.mode		= 0644,
-		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= (void *)SYSCTL_ZERO,
-		.extra2		= (void *)SYSCTL_ONE,
-	},
-	{
-		.procname	= "accept_untracked_na",
-		.data		= &ipv6_devconf.accept_untracked_na,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_TWO,
-	},
-	{
-		.procname	= "force_forwarding",
-		.data		= &ipv6_devconf.force_forwarding,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= addrconf_sysctl_force_forwarding,
-	},
+ADDRCONF_DATA(void, enhanced_dad)
+ADDRCONF_DATA(void, addr_gen_mode)
+ADDRCONF_DATA(void, disable_policy)
+ADDRCONF_DATA(int, ndisc_tclass)
+ADDRCONF_DATA(int, rpl_seg_enabled)
+ADDRCONF_DATA(u8, ioam6_enabled)
+ADDRCONF_DATA(unsigned int, ioam6_id)
+ADDRCONF_DATA(unsigned int, ioam6_id_wide)
+ADDRCONF_DATA(u8, ndisc_evict_nocarrier)
+ADDRCONF_DATA(int, accept_untracked_na)
+ADDRCONF_DATA(void, force_forwarding)
+
+static const struct sysctl_field addrconf_sysctl[] = {
+	ADDRCONF_CUSTOM_ENTRY(forwarding, "forwarding", 0644, sizeof(int),
+			      addrconf_sysctl_forward),
+	ADDRCONF_INT_MINMAX_ENTRY(hop_limit, "hop_limit", SYSCTL_ONE,
+				  &two_five_five),
+	ADDRCONF_CUSTOM_ENTRY(mtu6, "mtu", 0644, sizeof(int),
+			      addrconf_sysctl_mtu),
+	ADDRCONF_INT_ENTRY(accept_ra, "accept_ra"),
+	ADDRCONF_INT_ENTRY(accept_redirects, "accept_redirects"),
+	ADDRCONF_INT_ENTRY(autoconf, "autoconf"),
+	ADDRCONF_INT_ENTRY(dad_transmits, "dad_transmits"),
+	ADDRCONF_INT_MINMAX_ENTRY(rtr_solicits, "router_solicitations",
+				  &minus_one, NULL),
+	ADDRCONF_CUSTOM_ENTRY(rtr_solicit_interval,
+			      "router_solicitation_interval", 0644,
+			      sizeof(int), proc_dointvec_jiffies),
+	ADDRCONF_CUSTOM_ENTRY(rtr_solicit_max_interval,
+			      "router_solicitation_max_interval", 0644,
+			      sizeof(int), proc_dointvec_jiffies),
+	ADDRCONF_CUSTOM_ENTRY(rtr_solicit_delay,
+			      "router_solicitation_delay", 0644,
+			      sizeof(int), proc_dointvec_jiffies),
+	ADDRCONF_INT_ENTRY(force_mld_version, "force_mld_version"),
+	ADDRCONF_CUSTOM_ENTRY(mldv1_unsolicited_report_interval,
+			      "mldv1_unsolicited_report_interval", 0644,
+			      sizeof(int), proc_dointvec_ms_jiffies),
+	ADDRCONF_CUSTOM_ENTRY(mldv2_unsolicited_report_interval,
+			      "mldv2_unsolicited_report_interval", 0644,
+			      sizeof(int), proc_dointvec_ms_jiffies),
+	ADDRCONF_INT_ENTRY(use_tempaddr, "use_tempaddr"),
+	ADDRCONF_INT_ENTRY(temp_valid_lft, "temp_valid_lft"),
+	ADDRCONF_INT_ENTRY(temp_prefered_lft, "temp_prefered_lft"),
+	ADDRCONF_INT_ENTRY(regen_min_advance, "regen_min_advance"),
+	ADDRCONF_INT_ENTRY(regen_max_retry, "regen_max_retry"),
+	ADDRCONF_INT_ENTRY(max_desync_factor, "max_desync_factor"),
+	ADDRCONF_INT_ENTRY(max_addresses, "max_addresses"),
+	ADDRCONF_INT_ENTRY(accept_ra_defrtr, "accept_ra_defrtr"),
+	ADDRCONF_UINT_MINMAX_ENTRY(ra_defrtr_metric, "ra_defrtr_metric",
+				   SYSCTL_UINT_ONE, NULL),
+	ADDRCONF_INT_ENTRY(accept_ra_min_hop_limit,
+			 "accept_ra_min_hop_limit"),
+	ADDRCONF_INT_ENTRY(accept_ra_min_lft, "accept_ra_min_lft"),
+	ADDRCONF_INT_ENTRY(accept_ra_pinfo, "accept_ra_pinfo"),
+	ADDRCONF_U8_MINMAX_ENTRY(ra_honor_pio_life, "ra_honor_pio_life",
+				 SYSCTL_UINT_ZERO, SYSCTL_UINT_ONE),
+	ADDRCONF_U8_MINMAX_ENTRY(ra_honor_pio_pflag, "ra_honor_pio_pflag",
+				 SYSCTL_UINT_ZERO, SYSCTL_UINT_ONE),
+#ifdef CONFIG_IPV6_ROUTER_PREF
+	ADDRCONF_INT_ENTRY(accept_ra_rtr_pref, "accept_ra_rtr_pref"),
+	ADDRCONF_CUSTOM_ENTRY(rtr_probe_interval, "router_probe_interval",
+			      0644, sizeof(int), proc_dointvec_jiffies),
+#ifdef CONFIG_IPV6_ROUTE_INFO
+	ADDRCONF_INT_ENTRY(accept_ra_rt_info_min_plen,
+			 "accept_ra_rt_info_min_plen"),
+	ADDRCONF_INT_ENTRY(accept_ra_rt_info_max_plen,
+			 "accept_ra_rt_info_max_plen"),
+#endif
+#endif
+	ADDRCONF_CUSTOM_ENTRY(proxy_ndp, "proxy_ndp", 0644, sizeof(int),
+			      addrconf_sysctl_proxy_ndp),
+	ADDRCONF_INT_ENTRY(accept_source_route, "accept_source_route"),
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+	ADDRCONF_INT_ENTRY(optimistic_dad, "optimistic_dad"),
+	ADDRCONF_INT_ENTRY(use_optimistic, "use_optimistic"),
+#endif
+#ifdef CONFIG_IPV6_MROUTE
+	ADDRCONF_CUSTOM_ENTRY(mc_forwarding, "mc_forwarding", 0444,
+			      sizeof(int), proc_dointvec),
+#endif
+	ADDRCONF_CUSTOM_ENTRY(disable_ipv6, "disable_ipv6", 0644,
+			      sizeof(int), addrconf_sysctl_disable),
+	ADDRCONF_INT_ENTRY(accept_dad, "accept_dad"),
+	ADDRCONF_INT_ENTRY(force_tllao, "force_tllao"),
+	ADDRCONF_INT_ENTRY(ndisc_notify, "ndisc_notify"),
+	ADDRCONF_INT_ENTRY(suppress_frag_ndisc, "suppress_frag_ndisc"),
+	ADDRCONF_INT_ENTRY(accept_ra_from_local, "accept_ra_from_local"),
+	ADDRCONF_INT_ENTRY(accept_ra_mtu, "accept_ra_mtu"),
+	ADDRCONF_CUSTOM_ENTRY(stable_secret, "stable_secret", 0600,
+			      IPV6_MAX_STRLEN, addrconf_sysctl_stable_secret),
+	ADDRCONF_INT_ENTRY(use_oif_addrs_only, "use_oif_addrs_only"),
+	ADDRCONF_CUSTOM_ENTRY(ignore_routes_with_linkdown,
+			      "ignore_routes_with_linkdown", 0644, sizeof(int),
+			      addrconf_sysctl_ignore_routes_with_linkdown),
+	ADDRCONF_INT_ENTRY(drop_unicast_in_l2_multicast,
+			 "drop_unicast_in_l2_multicast"),
+	ADDRCONF_INT_ENTRY(drop_unsolicited_na, "drop_unsolicited_na"),
+	ADDRCONF_INT_ENTRY(keep_addr_on_down, "keep_addr_on_down"),
+	ADDRCONF_INT_ENTRY(seg6_enabled, "seg6_enabled"),
+#ifdef CONFIG_IPV6_SEG6_HMAC
+	ADDRCONF_INT_ENTRY(seg6_require_hmac, "seg6_require_hmac"),
+#endif
+	ADDRCONF_CUSTOM_ENTRY(enhanced_dad, "enhanced_dad", 0644,
+			      sizeof(int), proc_dointvec),
+	ADDRCONF_CUSTOM_ENTRY(addr_gen_mode, "addr_gen_mode", 0644,
+			      sizeof(int), addrconf_sysctl_addr_gen_mode),
+	ADDRCONF_CUSTOM_ENTRY(disable_policy, "disable_policy", 0644,
+			      sizeof(int), addrconf_sysctl_disable_policy),
+	ADDRCONF_INT_MINMAX_ENTRY(ndisc_tclass, "ndisc_tclass",
+				  SYSCTL_ZERO, &two_five_five),
+	ADDRCONF_INT_MINMAX_ENTRY(rpl_seg_enabled, "rpl_seg_enabled",
+				  SYSCTL_ZERO, SYSCTL_ONE),
+	ADDRCONF_U8_MINMAX_ENTRY(ioam6_enabled, "ioam6_enabled",
+				 SYSCTL_UINT_ZERO, SYSCTL_UINT_ONE),
+	ADDRCONF_UINT_MINMAX_ENTRY(ioam6_id, "ioam6_id",
+				   SYSCTL_UINT_ZERO, &ioam6_if_id_max),
+	ADDRCONF_UINT_ENTRY(ioam6_id_wide, "ioam6_id_wide"),
+	ADDRCONF_U8_MINMAX_ENTRY(ndisc_evict_nocarrier,
+				 "ndisc_evict_nocarrier", SYSCTL_UINT_ZERO,
+				 SYSCTL_UINT_ONE),
+	ADDRCONF_INT_MINMAX_ENTRY(accept_untracked_na, "accept_untracked_na",
+				  SYSCTL_ZERO, SYSCTL_TWO),
+	ADDRCONF_CUSTOM_ENTRY(force_forwarding, "force_forwarding", 0644,
+			      sizeof(int), addrconf_sysctl_force_forwarding),
 };
 
 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
 		struct inet6_dev *idev, struct ipv6_devconf *p)
 {
-	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
-	int i, ifindex;
-	struct ctl_table *table;
+	struct addrconf_ctl_context ctx = {
+		.context.ns.net_ns = net,
+		.devconf = p,
+	};
+	int ifindex;
 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
 
-	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
-	if (!table)
-		goto out;
-
-	for (i = 0; i < table_size; i++) {
-		table[i].data += (char *)p - (char *)&ipv6_devconf;
-		/* If one of these is already set, then it is not safe to
-		 * overwrite either of them: this makes proc_dointvec_minmax
-		 * usable.
-		 */
-		if (!table[i].extra1 && !table[i].extra2) {
-			table[i].extra1 = idev; /* embedded; no ref */
-			table[i].extra2 = net;
-		}
-	}
-
 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
 
-	p->sysctl_header = register_net_sysctl_sz(net, path, table,
-						  table_size);
+	p->sysctl_header = register_sysctl_fields_ctx(&net->sysctls, path,
+						      addrconf_sysctl, &ctx);
 	if (!p->sysctl_header)
-		goto free;
+		goto out;
 
 	if (!strcmp(dev_name, "all"))
 		ifindex = NETCONFA_IFINDEX_ALL;
@@ -7347,8 +7111,6 @@ static int __addrconf_sysctl_register(struct net *net, char *dev_name,
 				     ifindex, p);
 	return 0;
 
-free:
-	kfree(table);
 out:
 	return -ENOBUFS;
 }
@@ -7356,15 +7118,11 @@ static int __addrconf_sysctl_register(struct net *net, char *dev_name,
 static void __addrconf_sysctl_unregister(struct net *net,
 					 struct ipv6_devconf *p, int ifindex)
 {
-	const struct ctl_table *table;
-
 	if (!p->sysctl_header)
 		return;
 
-	table = p->sysctl_header->ctl_table_arg;
 	unregister_net_sysctl_table(p->sysctl_header);
 	p->sysctl_header = NULL;
-	kfree(table);
 
 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
 }
-- 
2.55.0