diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index b57308e76b1d3223dec0e97ae5c4496441f0f38e..eaee2c8d4c00add74b162bbcdeb555934586cf24 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1461,11 +1461,20 @@ accept_ra_pinfo - BOOLEAN
 	Functional default: enabled if accept_ra is enabled.
 			    disabled if accept_ra is disabled.
 
+accept_ra_rt_info_min_plen - INTEGER
+	Minimum prefix length of Route Information in RA.
+
+	Route Information w/ prefix smaller than this variable shall
+	be ignored.
+
+	Functional default: 0 if accept_ra_rtr_pref is enabled.
+			    -1 if accept_ra_rtr_pref is disabled.
+
 accept_ra_rt_info_max_plen - INTEGER
 	Maximum prefix length of Route Information in RA.
 
-	Route Information w/ prefix larger than or equal to this
-	variable shall be ignored.
+	Route Information w/ prefix larger than this variable shall
+	be ignored.
 
 	Functional default: 0 if accept_ra_rtr_pref is enabled.
 			    -1 if accept_ra_rtr_pref is disabled.
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index f0d79bd054cab9eed7a2d63058f25a3a6abd8bbf..e1b442996f810529a755533270b6d21c350fbd5a 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -37,6 +37,7 @@ struct ipv6_devconf {
 	__s32		accept_ra_rtr_pref;
 	__s32		rtr_probe_interval;
 #ifdef CONFIG_IPV6_ROUTE_INFO
+	__s32		accept_ra_rt_info_min_plen;
 	__s32		accept_ra_rt_info_max_plen;
 #endif
 #endif
diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
index d8f6a1ac9af49605ff67675d4639bca493da5edb..2ae59178189d7983fb9ed99ae1cd5f40197cfb04 100644
--- a/include/uapi/linux/ipv6.h
+++ b/include/uapi/linux/ipv6.h
@@ -184,6 +184,7 @@ enum {
 	DEVCONF_ENHANCED_DAD,
 	DEVCONF_ADDR_GEN_MODE,
 	DEVCONF_DISABLE_POLICY,
+	DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN,
 	DEVCONF_MAX
 };
 
diff --git a/include/uapi/linux/sysctl.h b/include/uapi/linux/sysctl.h
index d2b12152e358f14e791ef3e842cb6eac7cc8ceec..e13d48058b8d0e5cf36e458e68e257d73a9a1e8f 100644
--- a/include/uapi/linux/sysctl.h
+++ b/include/uapi/linux/sysctl.h
@@ -568,6 +568,7 @@ enum {
 	NET_IPV6_PROXY_NDP=23,
 	NET_IPV6_ACCEPT_SOURCE_ROUTE=25,
 	NET_IPV6_ACCEPT_RA_FROM_LOCAL=26,
+	NET_IPV6_ACCEPT_RA_RT_INFO_MIN_PLEN=27,
 	__NET_IPV6_MAX
 };
 
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 8c69768a5c4606548333842e86b1416a7897ebf5..dff5beb26a01df67ef69188cdbf494db41fc7942 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -224,6 +224,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
 	.accept_ra_rtr_pref	= 1,
 	.rtr_probe_interval	= 60 * HZ,
 #ifdef CONFIG_IPV6_ROUTE_INFO
+	.accept_ra_rt_info_min_plen = 0,
 	.accept_ra_rt_info_max_plen = 0,
 #endif
 #endif
@@ -277,6 +278,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
 	.accept_ra_rtr_pref	= 1,
 	.rtr_probe_interval	= 60 * HZ,
 #ifdef CONFIG_IPV6_ROUTE_INFO
+	.accept_ra_rt_info_min_plen = 0,
 	.accept_ra_rt_info_max_plen = 0,
 #endif
 #endif
@@ -4979,6 +4981,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
 	array[DEVCONF_RTR_PROBE_INTERVAL] =
 		jiffies_to_msecs(cnf->rtr_probe_interval);
 #ifdef CONFIG_IPV6_ROUTE_INFO
+	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
 #endif
 #endif
@@ -6121,6 +6124,13 @@ static const struct ctl_table addrconf_sysctl[] = {
 		.proc_handler	= proc_dointvec_jiffies,
 	},
 #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,
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 112ccbc0a8ac4f78ebf1eca19c62052bcefeaf6d..b5812b3f75399df98ec3b487dc69f07ff01bc35f 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1418,6 +1418,8 @@ static void ndisc_router_discovery(struct sk_buff *skb)
 			if (ri->prefix_len == 0 &&
 			    !in6_dev->cnf.accept_ra_defrtr)
 				continue;
+			if (ri->prefix_len < in6_dev->cnf.accept_ra_rt_info_min_plen)
+				continue;
 			if (ri->prefix_len > in6_dev->cnf.accept_ra_rt_info_max_plen)
 				continue;
 			rt6_route_rcv(skb->dev, (u8 *)p, (p->nd_opt_len) << 3,