--- zzzz-none-000/linux-2.6.39.4/kernel/sysctl_binary.c	2011-08-03 19:43:28.000000000 +0000
+++ puma6-arm-6490-729/linux-2.6.39.4/kernel/sysctl_binary.c	2021-11-10 13:23:10.000000000 +0000
@@ -523,6 +523,9 @@
 	{ CTL_INT,	NET_IPV6_ACCEPT_RA_RT_INFO_MAX_PLEN,	"accept_ra_rt_info_max_plen" },
 	{ CTL_INT,	NET_IPV6_PROXY_NDP,			"proxy_ndp" },
 	{ CTL_INT,	NET_IPV6_ACCEPT_SOURCE_ROUTE,		"accept_source_route" },
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+	{ CTL_INT,	NET_IPV6_RA_DEFRTR_TABLE,		"ra_defrtr_table" },
+#endif
 	{}
 };
 
@@ -971,7 +974,6 @@
 static ssize_t bin_intvec(struct file *file,
 	void __user *oldval, size_t oldlen, void __user *newval, size_t newlen)
 {
-	mm_segment_t old_fs = get_fs();
 	ssize_t copied = 0;
 	char *buffer;
 	ssize_t result;
@@ -984,13 +986,10 @@
 	if (oldval && oldlen) {
 		unsigned __user *vec = oldval;
 		size_t length = oldlen / sizeof(*vec);
-		loff_t pos = 0;
 		char *str, *end;
 		int i;
 
-		set_fs(KERNEL_DS);
-		result = vfs_read(file, buffer, BUFSZ - 1, &pos);
-		set_fs(old_fs);
+		result = kernel_read(file, 0, buffer, BUFSZ - 1);
 		if (result < 0)
 			goto out_kfree;
 
@@ -1017,7 +1016,6 @@
 	if (newval && newlen) {
 		unsigned __user *vec = newval;
 		size_t length = newlen / sizeof(*vec);
-		loff_t pos = 0;
 		char *str, *end;
 		int i;
 
@@ -1033,9 +1031,7 @@
 			str += snprintf(str, end - str, "%lu\t", value);
 		}
 
-		set_fs(KERNEL_DS);
-		result = vfs_write(file, buffer, str - buffer, &pos);
-		set_fs(old_fs);
+		result = kernel_write(file, buffer, str - buffer, 0);
 		if (result < 0)
 			goto out_kfree;
 	}
@@ -1049,7 +1045,6 @@
 static ssize_t bin_ulongvec(struct file *file,
 	void __user *oldval, size_t oldlen, void __user *newval, size_t newlen)
 {
-	mm_segment_t old_fs = get_fs();
 	ssize_t copied = 0;
 	char *buffer;
 	ssize_t result;
@@ -1062,13 +1057,10 @@
 	if (oldval && oldlen) {
 		unsigned long __user *vec = oldval;
 		size_t length = oldlen / sizeof(*vec);
-		loff_t pos = 0;
 		char *str, *end;
 		int i;
 
-		set_fs(KERNEL_DS);
-		result = vfs_read(file, buffer, BUFSZ - 1, &pos);
-		set_fs(old_fs);
+		result = kernel_read(file, 0, buffer, BUFSZ - 1);
 		if (result < 0)
 			goto out_kfree;
 
@@ -1095,7 +1087,6 @@
 	if (newval && newlen) {
 		unsigned long __user *vec = newval;
 		size_t length = newlen / sizeof(*vec);
-		loff_t pos = 0;
 		char *str, *end;
 		int i;
 
@@ -1111,9 +1102,7 @@
 			str += snprintf(str, end - str, "%lu\t", value);
 		}
 
-		set_fs(KERNEL_DS);
-		result = vfs_write(file, buffer, str - buffer, &pos);
-		set_fs(old_fs);
+		result = kernel_write(file, buffer, str - buffer, 0);
 		if (result < 0)
 			goto out_kfree;
 	}
@@ -1127,19 +1116,15 @@
 static ssize_t bin_uuid(struct file *file,
 	void __user *oldval, size_t oldlen, void __user *newval, size_t newlen)
 {
-	mm_segment_t old_fs = get_fs();
 	ssize_t result, copied = 0;
 
 	/* Only supports reads */
 	if (oldval && oldlen) {
-		loff_t pos = 0;
 		char buf[40], *str = buf;
 		unsigned char uuid[16];
 		int i;
 
-		set_fs(KERNEL_DS);
-		result = vfs_read(file, buf, sizeof(buf) - 1, &pos);
-		set_fs(old_fs);
+		result = kernel_read(file, 0, buf, sizeof(buf) - 1);
 		if (result < 0)
 			goto out;
 
@@ -1175,18 +1160,14 @@
 static ssize_t bin_dn_node_address(struct file *file,
 	void __user *oldval, size_t oldlen, void __user *newval, size_t newlen)
 {
-	mm_segment_t old_fs = get_fs();
 	ssize_t result, copied = 0;
 
 	if (oldval && oldlen) {
-		loff_t pos = 0;
 		char buf[15], *nodep;
 		unsigned long area, node;
 		__le16 dnaddr;
 
-		set_fs(KERNEL_DS);
-		result = vfs_read(file, buf, sizeof(buf) - 1, &pos);
-		set_fs(old_fs);
+		result = kernel_read(file, 0, buf, sizeof(buf) - 1);
 		if (result < 0)
 			goto out;
 
@@ -1215,7 +1196,6 @@
 	}
 
 	if (newval && newlen) {
-		loff_t pos = 0;
 		__le16 dnaddr;
 		char buf[15];
 		int len;
@@ -1232,9 +1212,7 @@
 				le16_to_cpu(dnaddr) >> 10,
 				le16_to_cpu(dnaddr) & 0x3ff);
 
-		set_fs(KERNEL_DS);
-		result = vfs_write(file, buf, len, &pos);
-		set_fs(old_fs);
+		result = kernel_write(file, buf, len, 0);
 		if (result < 0)
 			goto out;
 	}