diff --git a/libc/arch-arm/krait/bionic/memcpy.S b/libc/arch-arm/krait/bionic/memcpy.S
index 0cd4d44..4a21709 100644
--- a/libc/arch-arm/krait/bionic/memcpy.S
+++ b/libc/arch-arm/krait/bionic/memcpy.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 The Android Open Source Project
+ * Copyright (C) 2013 The Android Open Source Project
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -45,9 +45,8 @@
 ENTRY(memcpy)
         .save       {r0, lr}
         /* start preloading as early as possible */
-        pld         [r1, #(CACHE_LINE_SIZE*0)]
+        pld         [r1, #(CACHE_LINE_SIZE*4)]
         stmfd       sp!, {r0, lr}
-        pld         [r1, #(CACHE_LINE_SIZE*2)]
 
         /* do we have at least 16-bytes to copy (needed for alignment below) */
         cmp         r2, #16
@@ -56,7 +55,7 @@
         /* align destination to cache-line for the write-buffer */
         rsb         r3, r0, #0
         ands        r3, r3, #0xF
-        beq         0f
+        beq         2f
 
         /* copy up to 15-bytes (count in r3) */
         sub         r2, r2, r3
@@ -76,47 +75,29 @@
         // copies 8 bytes, destination 64-bits aligned
         vld1.8      {d0}, [r1]!
         vst1.8      {d0}, [r0, :64]!
-2:
 
-0:      /* preload immediately the next cache line, which we may need */
-        pld         [r1, #(CACHE_LINE_SIZE*0)]
-        pld         [r1, #(CACHE_LINE_SIZE*2)]
-
-        /* make sure we have at least 64 bytes to copy */
+2:      /* make sure we have at least 64 bytes to copy */
         subs        r2, r2, #64
         blo         2f
 
-        /* Preload all the cache lines we need.
-         * NOTE: The number of pld below depends on CACHE_LINE_SIZE,
-         * ideally we would increase the distance in the main loop to
-         * avoid the goofy code below. In practice this doesn't seem to make
-         * a big difference.
-         * NOTE: The value CACHE_LINE_SIZE * 8 was chosen through
-         * experimentation.
-         */
-        pld         [r1, #(CACHE_LINE_SIZE*4)]
-        pld         [r1, #(CACHE_LINE_SIZE*6)]
-        pld         [r1, #(CACHE_LINE_SIZE*8)]
-
 1:      /* The main loop copies 64 bytes at a time */
         vld1.8      {d0  - d3},   [r1]!
         vld1.8      {d4  - d7},   [r1]!
-        pld         [r1, #(CACHE_LINE_SIZE*8)]
+        pld         [r1, #(CACHE_LINE_SIZE*2)]
         subs        r2, r2, #64
         vst1.8      {d0  - d3},   [r0, :128]!
         vst1.8      {d4  - d7},   [r0, :128]!
         bhs         1b
 
 2:      /* fix-up the remaining count and make sure we have >= 32 bytes left */
-        add         r2, r2, #64
-        subs        r2, r2, #32
+        adds        r2, r2, #32
         blo         4f
 
-3:      /* 32 bytes at a time. These cache lines were already preloaded */
+        /* Copy 32 bytes. These cache lines were already preloaded */
         vld1.8      {d0 - d3},  [r1]!
-        subs        r2, r2, #32
+        sub         r2, r2, #32
         vst1.8      {d0 - d3},  [r0, :128]!
-        bhs         3b
+
 4:      /* less than 32 left */
         add         r2, r2, #32
         tst         r2, #0x10
diff --git a/libc/bionic/mmap.c b/libc/bionic/mmap.c
index 40a6538..36aee85 100644
--- a/libc/bionic/mmap.c
+++ b/libc/bionic/mmap.c
@@ -34,10 +34,18 @@
 #define  MMAP2_SHIFT  12
 void* mmap(void *addr, size_t size, int prot, int flags, int fd, long offset)
 {
+    void *ret;
+
     if (offset & ((1UL << MMAP2_SHIFT)-1)) {
         errno = EINVAL;
         return MAP_FAILED;
     }
 
-    return __mmap2(addr, size, prot, flags, fd, (size_t)offset >> MMAP2_SHIFT);
+    ret = __mmap2(addr, size, prot, flags, fd, (size_t)offset >> MMAP2_SHIFT);
+
+    if ((ret != MAP_FAILED) && (flags & (MAP_PRIVATE | MAP_ANONYMOUS))) {
+        madvise(ret, size, MADV_MERGEABLE);
+    }
+
+    return ret;
 }
diff --git a/libc/include/netdb.h b/libc/include/netdb.h
index 3ea512c..62a7a3c 100644
--- a/libc/include/netdb.h
+++ b/libc/include/netdb.h
@@ -207,13 +207,13 @@
 void endservent(void);
 void freehostent(struct hostent *);
 struct hostent	*gethostbyaddr(const void *, socklen_t, int);
-struct hostent	*android_gethostbyaddrforiface(const void *, socklen_t, int, const char*);
+struct hostent	*android_gethostbyaddrforiface(const void *, socklen_t, int, const char*, int);
 int gethostbyaddr_r(const void *, int, int, struct hostent *, char *, size_t, struct hostent **, int *);
 struct hostent	*gethostbyname(const char *);
 int gethostbyname_r(const char *, struct hostent *, char *, size_t, struct hostent **, int *);
 struct hostent	*gethostbyname2(const char *, int);
 int gethostbyname2_r(const char *, int, struct hostent *, char *, size_t, struct hostent **, int *);
-struct hostent	*android_gethostbynameforiface(const char *, int, const char *);
+struct hostent	*android_gethostbynameforiface(const char *, int, const char *, int);
 struct hostent	*gethostent(void);
 int gethostent_r(struct hostent *, char *, size_t, struct hostent **, int *);
 struct hostent	*getipnodebyaddr(const void *, size_t, int, int *);
@@ -241,9 +241,9 @@
 void setnetent(int);
 void setprotoent(int);
 int getaddrinfo(const char *, const char *, const struct addrinfo *, struct addrinfo **);
-int android_getaddrinfoforiface(const char *, const char *, const struct addrinfo *, const char *, struct addrinfo **);
+int android_getaddrinfoforiface(const char *, const char *, const struct addrinfo *, const char *, int, struct addrinfo **);
 int getnameinfo(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int);
-int android_getnameinfoforiface(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int, const char *);
+int android_getnameinfoforiface(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int, const char *, int);
 void freeaddrinfo(struct addrinfo *);
 const char	*gai_strerror(int);
 void setnetgrent(const char *);
diff --git a/libc/netbsd/gethnamaddr.c b/libc/netbsd/gethnamaddr.c
index ee5052e..5b2f987 100644
--- a/libc/netbsd/gethnamaddr.c
+++ b/libc/netbsd/gethnamaddr.c
@@ -126,7 +126,7 @@
 static int _dns_gethtbyaddr(void *, void *, va_list);
 static int _dns_gethtbyname(void *, void *, va_list);
 
-static struct hostent *gethostbyname_internal(const char *, int, res_state, const char *);
+static struct hostent *gethostbyname_internal(const char *, int, res_state, const char *, int);
 
 static const ns_src default_dns_files[] = {
 	{ NSSRC_FILES, 	NS_SUCCESS },
@@ -497,13 +497,13 @@
 
 	/* try IPv6 first - if that fails do IPv4 */
 	if (res->options & RES_USE_INET6) {
-		hp = gethostbyname_internal(name, AF_INET6, res, NULL);
+		hp = gethostbyname_internal(name, AF_INET6, res, NULL, 0);
 		if (hp) {
 			__res_put_state(res);
 			return hp;
 		}
 	}
-	hp = gethostbyname_internal(name, AF_INET, res, NULL);
+	hp = gethostbyname_internal(name, AF_INET, res, NULL, 0);
 	__res_put_state(res);
 	return hp;
 }
@@ -511,18 +511,18 @@
 struct hostent *
 gethostbyname2(const char *name, int af)
 {
-	return android_gethostbynameforiface(name, af, NULL);
+	return android_gethostbynameforiface(name, af, NULL, 0);
 }
 
 struct hostent *
-android_gethostbynameforiface(const char *name, int af, const char *iface)
+android_gethostbynameforiface(const char *name, int af, const char *iface, int mark)
 {
 	struct hostent *hp;
 	res_state res = __res_get_state();
 
 	if (res == NULL)
 		return NULL;
-	hp = gethostbyname_internal(name, af, res, iface);
+	hp = gethostbyname_internal(name, af, res, iface, mark);
 	__res_put_state(res);
 	return hp;
 }
@@ -741,7 +741,7 @@
 
 // very similar in proxy-ness to android_getaddrinfo_proxy
 static struct hostent *
-gethostbyname_internal(const char *name, int af, res_state res, const char *iface)
+gethostbyname_internal(const char *name, int af, res_state res, const char *iface, int mark)
 {
 	const char *cache_mode = getenv("ANDROID_DNS_MODE");
 	FILE* proxy = NULL;
@@ -749,6 +749,7 @@
 
 	if (cache_mode != NULL && strcmp(cache_mode, "local") == 0) {
 		res_setiface(res, iface);
+		res_setmark(res, mark);
 		return gethostbyname_internal_real(name, af, res);
 	}
 
@@ -780,7 +781,7 @@
 
 struct hostent *
 android_gethostbyaddrforiface_proxy(const void *addr,
-    socklen_t len, int af, const char* iface)
+    socklen_t len, int af, const char* iface, int mark)
 {
 	struct hostent *result = NULL;
 	FILE* proxy = android_open_proxy();
@@ -810,7 +811,7 @@
 
 struct hostent *
 android_gethostbyaddrforiface_real(const void *addr,
-    socklen_t len, int af, const char* iface)
+    socklen_t len, int af, const char* iface, int mark)
 {
 	const u_char *uaddr = (const u_char *)addr;
 	socklen_t size;
@@ -858,28 +859,28 @@
 	hp = NULL;
 	h_errno = NETDB_INTERNAL;
 	if (nsdispatch(&hp, dtab, NSDB_HOSTS, "gethostbyaddr",
-	    default_dns_files, uaddr, len, af, iface) != NS_SUCCESS)
+		default_dns_files, uaddr, len, af, iface, mark) != NS_SUCCESS)
 		return NULL;
 	h_errno = NETDB_SUCCESS;
 	return hp;
 }
 
 struct hostent *
-android_gethostbyaddrforiface(const void *addr, socklen_t len, int af, const char* iface)
+android_gethostbyaddrforiface(const void *addr, socklen_t len, int af, const char* iface, int mark)
 {
 	const char *cache_mode = getenv("ANDROID_DNS_MODE");
 
 	if (cache_mode == NULL || strcmp(cache_mode, "local") != 0) {
-		return android_gethostbyaddrforiface_proxy(addr, len, af, iface);
+		return android_gethostbyaddrforiface_proxy(addr, len, af, iface, mark);
 	} else {
-		return android_gethostbyaddrforiface_real(addr,len, af,iface);
+		return android_gethostbyaddrforiface_real(addr,len, af, iface, mark);
 	}
 }
 
 struct hostent *
 gethostbyaddr(const void *addr, socklen_t len, int af)
 {
-	return android_gethostbyaddrforiface(addr, len, af, NULL);
+	return android_gethostbyaddrforiface(addr, len, af, NULL, 0);
 }
 
 
@@ -1315,6 +1316,7 @@
 	int len, af, advance;
 	res_state res;
 	const char* iface;
+	int mark;
 	res_static rs = __res_get_static();
 
 	assert(rv != NULL);
@@ -1323,6 +1325,7 @@
 	len = va_arg(ap, int);
 	af = va_arg(ap, int);
 	iface = va_arg(ap, char *);
+	mark = va_arg(ap, int);
 
 	switch (af) {
 	case AF_INET:
@@ -1365,6 +1368,7 @@
 		return NS_NOTFOUND;
 	}
 	res_setiface(res, iface);
+	res_setmark(res, mark);
 	n = res_nquery(res, qbuf, C_IN, T_PTR, buf->buf, sizeof(buf->buf));
 	if (n < 0) {
 		free(buf);
diff --git a/libc/netbsd/net/getaddrinfo.c b/libc/netbsd/net/getaddrinfo.c
index 401bc6e..0a5e436 100644
--- a/libc/netbsd/net/getaddrinfo.c
+++ b/libc/netbsd/net/getaddrinfo.c
@@ -214,7 +214,7 @@
 
 static int str2number(const char *);
 static int explore_fqdn(const struct addrinfo *, const char *,
-	const char *, struct addrinfo **, const char *iface);
+	const char *, struct addrinfo **, const char *iface, int mark);
 static int explore_null(const struct addrinfo *,
 	const char *, struct addrinfo **);
 static int explore_numeric(const struct addrinfo *, const char *,
@@ -577,12 +577,12 @@
 getaddrinfo(const char *hostname, const char *servname,
     const struct addrinfo *hints, struct addrinfo **res)
 {
-	return android_getaddrinfoforiface(hostname, servname, hints, NULL, res);
+	return android_getaddrinfoforiface(hostname, servname, hints, NULL, 0, res);
 }
 
 int
 android_getaddrinfoforiface(const char *hostname, const char *servname,
-    const struct addrinfo *hints, const char *iface, struct addrinfo **res)
+    const struct addrinfo *hints, const char *iface, int mark, struct addrinfo **res)
 {
 	struct addrinfo sentinel;
 	struct addrinfo *cur;
@@ -761,7 +761,7 @@
 			pai->ai_protocol = ex->e_protocol;
 
 		error = explore_fqdn(pai, hostname, servname,
-			&cur->ai_next, iface);
+			&cur->ai_next, iface, mark);
 
 		while (cur && cur->ai_next)
 			cur = cur->ai_next;
@@ -794,7 +794,7 @@
  */
 static int
 explore_fqdn(const struct addrinfo *pai, const char *hostname,
-    const char *servname, struct addrinfo **res, const char *iface)
+    const char *servname, struct addrinfo **res, const char *iface, int mark)
 {
 	struct addrinfo *result;
 	struct addrinfo *cur;
@@ -820,7 +820,7 @@
 		return 0;
 
 	switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
-			default_dns_files, hostname, pai, iface)) {
+			default_dns_files, hostname, pai, iface, mark)) {
 	case NS_TRYAGAIN:
 		error = EAI_AGAIN;
 		goto free;
@@ -1889,10 +1889,12 @@
 	struct res_target q, q2;
 	res_state res;
 	const char* iface;
+	int mark;
 
 	name = va_arg(ap, char *);
 	pai = va_arg(ap, const struct addrinfo *);
 	iface = va_arg(ap, char *);
+	mark = va_arg(ap, int);
 	//fprintf(stderr, "_dns_getaddrinfo() name = '%s'\n", name);
 
 	memset(&q, 0, sizeof(q));
@@ -1980,6 +1982,7 @@
 	 * and have a cache hit that would be wasted, so we do the rest there on miss
 	 */
 	res_setiface(res, iface);
+	res_setmark(res, mark);
 	if (res_searchN(name, &q, res) < 0) {
 		__res_put_state(res);
 		free(buf);
diff --git a/libc/netbsd/net/getnameinfo.c b/libc/netbsd/net/getnameinfo.c
index ade5240..15d2675 100644
--- a/libc/netbsd/net/getnameinfo.c
+++ b/libc/netbsd/net/getnameinfo.c
@@ -93,7 +93,7 @@
 };
 
 static int getnameinfo_inet(const struct sockaddr *, socklen_t, char *,
-    socklen_t, char *, socklen_t, int, const char*);
+    socklen_t, char *, socklen_t, int, const char*, int);
 #ifdef INET6
 static int ip6_parsenumeric(const struct sockaddr *, const char *, char *,
 				 socklen_t, int);
@@ -108,16 +108,16 @@
  */
 int getnameinfo(const struct sockaddr* sa, socklen_t salen, char* host, size_t hostlen, char* serv, size_t servlen, int flags)
 {
-	return android_getnameinfoforiface(sa, salen, host, hostlen, serv, servlen, flags, NULL);
+	return android_getnameinfoforiface(sa, salen, host, hostlen, serv, servlen, flags, NULL, 0);
 }
 
-int android_getnameinfoforiface(const struct sockaddr* sa, socklen_t salen, char* host, size_t hostlen, char* serv, size_t servlen, int flags, const char* iface)
+int android_getnameinfoforiface(const struct sockaddr* sa, socklen_t salen, char* host, size_t hostlen, char* serv, size_t servlen, int flags, const char* iface, int mark)
 {
 	switch (sa->sa_family) {
 	case AF_INET:
 	case AF_INET6:
 		return getnameinfo_inet(sa, salen, host, hostlen,
-				serv, servlen, flags, iface);
+				serv, servlen, flags, iface, mark);
 	case AF_LOCAL:
 		return getnameinfo_local(sa, salen, host, hostlen,
 		    serv, servlen, flags);
@@ -158,10 +158,10 @@
  * the address. On failure -1 is returned in which case
  * normal execution flow shall continue. */
 static int
-android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, socklen_t addrLen, int addrFamily, const char* iface)
+android_gethostbyaddr_proxy(char* nameBuf, size_t nameBufLen, const void *addr, socklen_t addrLen, int addrFamily, const char* iface, int mark)
 {
 	struct hostent *hostResult =
-			android_gethostbyaddrforiface_proxy(addr, addrLen, addrFamily, iface);
+			android_gethostbyaddrforiface_proxy(addr, addrLen, addrFamily, iface, mark);
 
 	if (hostResult == NULL) return 0;
 
@@ -179,7 +179,7 @@
 getnameinfo_inet(const struct sockaddr* sa, socklen_t salen,
        char *host, socklen_t hostlen,
        char *serv, socklen_t servlen,
-       int flags, const char* iface)
+       int flags, const char* iface, int mark)
 {
 	const struct afd *afd;
 	struct servent *sp;
@@ -321,14 +321,15 @@
 		char android_proxy_buf[MAXDNAME];
 
 		int hostnamelen = android_gethostbyaddr_proxy(android_proxy_buf,
-				MAXDNAME, addr, afd->a_addrlen, afd->a_af, iface);
+				MAXDNAME, addr, afd->a_addrlen, afd->a_af, iface, mark);
 		if (hostnamelen > 0) {
 			hp = &android_proxy_hostent;
 			hp->h_name = android_proxy_buf;
 		} else if (!hostnamelen) {
 			hp = NULL;
 		} else {
-			hp = android_gethostbyaddrforiface(addr, afd->a_addrlen, afd->a_af, iface);
+			hp = android_gethostbyaddrforiface(addr, afd->a_addrlen, afd->a_af,
+					iface, mark);
 		}
 
 		if (hp) {
diff --git a/libc/netbsd/resolv/res_cache.c b/libc/netbsd/resolv/res_cache.c
index 829bf10..8e1bd14 100644
--- a/libc/netbsd/resolv/res_cache.c
+++ b/libc/netbsd/resolv/res_cache.c
@@ -1258,6 +1258,12 @@
     char                            ifname[IF_NAMESIZE + 1];
     struct resolv_pidiface_info*    next;
 } PidIfaceInfo;
+typedef struct resolv_uidiface_info {
+    int                             uid_start;
+    int                             uid_end;
+    char                            ifname[IF_NAMESIZE + 1];
+    struct resolv_uidiface_info*    next;
+} UidIfaceInfo;
 
 #define  HTABLE_VALID(x)  ((x) != NULL && (x) != HTABLE_DELETED)
 
@@ -1796,6 +1802,9 @@
 // List of pid iface pairs
 static struct resolv_pidiface_info _res_pidiface_list;
 
+// List of uid iface pairs
+static struct resolv_uidiface_info _res_uidiface_list;
+
 // name of the current default inteface
 static char            _res_default_ifname[IF_NAMESIZE + 1];
 
@@ -1805,6 +1814,9 @@
 // lock protecting the _res_pid_iface_list
 static pthread_mutex_t _res_pidiface_list_lock;
 
+// lock protecting the _res_uidiface_list
+static pthread_mutex_t _res_uidiface_list_lock;
+
 /* lookup the default interface name */
 static char *_get_default_iface_locked();
 /* find the first cache that has an associated interface and return the name of the interface */
@@ -1833,12 +1845,19 @@
 /* return 1 if the provided list of name servers differs from the list of name servers
  * currently attached to the provided cache_info */
 static int _resolv_is_nameservers_equal_locked(struct resolv_cache_info* cache_info,
-        char** servers, int numservers);
+        const char** servers, int numservers);
 /* remove a resolv_pidiface_info structure from _res_pidiface_list */
 static void _remove_pidiface_info_locked(int pid);
 /* get a resolv_pidiface_info structure from _res_pidiface_list with a certain pid */
 static struct resolv_pidiface_info* _get_pid_iface_info_locked(int pid);
 
+/* remove a resolv_pidiface_info structure from _res_uidiface_list */
+static int _remove_uidiface_info_locked(int uid_start, int uid_end);
+/* check if a range [low,high] overlaps with any already existing ranges in the uid=>iface map*/
+static int  _resolv_check_uid_range_overlap_locked(int uid_start, int uid_end);
+/* get a resolv_uidiface_info structure from _res_uidiface_list with a certain uid */
+static struct resolv_uidiface_info* _get_uid_iface_info_locked(int uid);
+
 static void
 _res_cache_init(void)
 {
@@ -1852,8 +1871,10 @@
     memset(&_res_default_ifname, 0, sizeof(_res_default_ifname));
     memset(&_res_cache_list, 0, sizeof(_res_cache_list));
     memset(&_res_pidiface_list, 0, sizeof(_res_pidiface_list));
+    memset(&_res_uidiface_list, 0, sizeof(_res_uidiface_list));
     pthread_mutex_init(&_res_cache_list_lock, NULL);
     pthread_mutex_init(&_res_pidiface_list_lock, NULL);
+    pthread_mutex_init(&_res_uidiface_list_lock, NULL);
 }
 
 struct resolv_cache*
@@ -2076,7 +2097,7 @@
 }
 
 void
-_resolv_set_nameservers_for_iface(const char* ifname, char** servers, int numservers,
+_resolv_set_nameservers_for_iface(const char* ifname, const char** servers, int numservers,
         const char *domains)
 {
     int i, rt, index;
@@ -2149,7 +2170,7 @@
 
 static int
 _resolv_is_nameservers_equal_locked(struct resolv_cache_info* cache_info,
-        char** servers, int numservers)
+        const char** servers, int numservers)
 {
     int i;
     char** ns;
@@ -2271,8 +2292,8 @@
         memcpy(&cache_info->ifaddr, addr, sizeof(*addr));
 
         if (DEBUG) {
-            char* addr_s = inet_ntoa(cache_info->ifaddr);
-            XLOG("address of interface %s is %s\n", ifname, addr_s);
+            XLOG("address of interface %s is %s\n",
+                    ifname, inet_ntoa(cache_info->ifaddr));
         }
     }
     pthread_mutex_unlock(&_res_cache_list_lock);
@@ -2411,26 +2432,183 @@
     return len;
 }
 
-int
-_resolv_get_default_iface(char* buff, int buffLen)
+static int
+_remove_uidiface_info_locked(int uid_start, int uid_end) {
+    struct resolv_uidiface_info* result = _res_uidiface_list.next;
+    struct resolv_uidiface_info* prev = &_res_uidiface_list;
+
+    while (result != NULL && result->uid_start != uid_start && result->uid_end != uid_end) {
+        prev = result;
+        result = result->next;
+    }
+    if (prev != NULL && result != NULL) {
+        prev->next = result->next;
+        free(result);
+        return 0;
+    }
+    errno = EINVAL;
+    return -1;
+}
+
+static struct resolv_uidiface_info*
+_get_uid_iface_info_locked(int uid)
 {
-    char* ifname;
+    struct resolv_uidiface_info* result = _res_uidiface_list.next;
+    while (result != NULL && !(result->uid_start <= uid && result->uid_end >= uid)) {
+        result = result->next;
+    }
+
+    return result;
+}
+
+static int
+_resolv_check_uid_range_overlap_locked(int uid_start, int uid_end)
+{
+    struct resolv_uidiface_info* cur = _res_uidiface_list.next;
+    while (cur != NULL) {
+        if (cur->uid_start <= uid_end && cur->uid_end >= uid_start) {
+            return -1;
+        }
+        cur = cur->next;
+    }
+    return 0;
+}
+
+void
+_resolv_clear_iface_uid_range_mapping()
+{
+    pthread_once(&_res_cache_once, _res_cache_init);
+    pthread_mutex_lock(&_res_uidiface_list_lock);
+    struct resolv_uidiface_info *current = _res_uidiface_list.next;
+    struct resolv_uidiface_info *next;
+    while (current != NULL) {
+        next = current->next;
+        free(current);
+        current = next;
+    }
+    _res_uidiface_list.next = NULL;
+    pthread_mutex_unlock(&_res_uidiface_list_lock);
+}
+
+void
+_resolv_clear_iface_pid_mapping()
+{
+    pthread_once(&_res_cache_once, _res_cache_init);
+    pthread_mutex_lock(&_res_pidiface_list_lock);
+    struct resolv_pidiface_info *current = _res_pidiface_list.next;
+    struct resolv_pidiface_info *next;
+    while (current != NULL) {
+        next = current->next;
+        free(current);
+        current = next;
+    }
+    _res_pidiface_list.next = NULL;
+    pthread_mutex_unlock(&_res_pidiface_list_lock);
+}
+
+int
+_resolv_set_iface_for_uid_range(const char* ifname, int uid_start, int uid_end)
+{
+    int rv = 0;
+    struct resolv_uidiface_info* uidiface_info;
+    // make sure the uid iface list is created
+    pthread_once(&_res_cache_once, _res_cache_init);
+    if (uid_start > uid_end) {
+        errno = EINVAL;
+        return -1;
+    }
+    pthread_mutex_lock(&_res_uidiface_list_lock);
+    //check that we aren't adding an overlapping range
+    if (!_resolv_check_uid_range_overlap_locked(uid_start, uid_end)) {
+        uidiface_info = calloc(sizeof(*uidiface_info), 1);
+        if (uidiface_info) {
+            uidiface_info->uid_start = uid_start;
+            uidiface_info->uid_end = uid_end;
+            int len = sizeof(uidiface_info->ifname);
+            strncpy(uidiface_info->ifname, ifname, len - 1);
+            uidiface_info->ifname[len - 1] = '\0';
+
+            uidiface_info->next = _res_uidiface_list.next;
+            _res_uidiface_list.next = uidiface_info;
+
+            XLOG("_resolv_set_iface_for_uid_range: [%d,%d], iface %s\n", low, high, ifname);
+        } else {
+            XLOG("_resolv_set_iface_for_uid_range failing calloc\n");
+            rv = -1;
+            errno = EINVAL;
+        }
+    } else {
+        XLOG("_resolv_set_iface_for_uid_range range [%d,%d] overlaps\n", low, high);
+        rv = -1;
+        errno = EINVAL;
+    }
+
+    pthread_mutex_unlock(&_res_uidiface_list_lock);
+    return rv;
+}
+
+int
+_resolv_clear_iface_for_uid_range(int uid_start, int uid_end)
+{
+    pthread_once(&_res_cache_once, _res_cache_init);
+    pthread_mutex_lock(&_res_uidiface_list_lock);
+
+    int rv = _remove_uidiface_info_locked(uid_start, uid_end);
+
+    XLOG("_resolv_clear_iface_for_uid_range: [%d,%d]\n", uid_start, uid_end);
+
+    pthread_mutex_unlock(&_res_uidiface_list_lock);
+
+    return rv;
+}
+
+int
+_resolv_get_uids_associated_interface(int uid, char* buff, int buffLen)
+{
     int len = 0;
 
-    if (!buff || buffLen == 0) {
+    if (!buff) {
         return -1;
     }
 
     pthread_once(&_res_cache_once, _res_cache_init);
+    pthread_mutex_lock(&_res_uidiface_list_lock);
+
+    struct resolv_uidiface_info* uidiface_info = _get_uid_iface_info_locked(uid);
+    buff[0] = '\0';
+    if (uidiface_info) {
+        len = strlen(uidiface_info->ifname);
+        if (len < buffLen) {
+            strncpy(buff, uidiface_info->ifname, len);
+            buff[len] = '\0';
+        }
+    }
+
+    XLOG("_resolv_get_uids_associated_interface buff: %s\n", buff);
+
+    pthread_mutex_unlock(&_res_uidiface_list_lock);
+
+    return len;
+}
+
+size_t
+_resolv_get_default_iface(char* buff, size_t buffLen)
+{
+    if (!buff || buffLen == 0) {
+        return 0;
+    }
+
+    pthread_once(&_res_cache_once, _res_cache_init);
     pthread_mutex_lock(&_res_cache_list_lock);
 
-    ifname = _get_default_iface_locked(); // never null, but may be empty
+    char* ifname = _get_default_iface_locked(); // never null, but may be empty
 
     // if default interface not set. Get first cache with an interface
     if (ifname[0] == '\0') {
         ifname = _find_any_iface_name_locked(); // may be null
     }
 
+    size_t len = 0;
     // if we got the default iface or if (no-default) the find_any call gave an answer
     if (ifname) {
         len = strlen(ifname);
@@ -2447,28 +2625,32 @@
     return len;
 }
 
-int
+void
 _resolv_populate_res_for_iface(res_state statp)
 {
-    int nserv;
-    struct resolv_cache_info* info = NULL;
+    if (statp == NULL) {
+        return;
+    }
 
-    if (statp) {
+    if (statp->iface[0] == '\0') { // no interface set assign default
+        size_t if_len = _resolv_get_default_iface(statp->iface, sizeof(statp->iface));
+        if (if_len + 1 > sizeof(statp->iface)) {
+            XLOG("%s: INTERNAL_ERROR: can't fit interface name into statp->iface.\n", __FUNCTION__);
+            return;
+        }
+        if (if_len == 0) {
+            XLOG("%s: INTERNAL_ERROR: can't find any suitable interfaces.\n", __FUNCTION__);
+            return;
+        }
+    }
+
+    pthread_once(&_res_cache_once, _res_cache_init);
+    pthread_mutex_lock(&_res_cache_list_lock);
+
+    struct resolv_cache_info* info = _find_cache_info_locked(statp->iface);
+    if (info != NULL) {
+        int nserv;
         struct addrinfo* ai;
-
-        if (statp->iface[0] == '\0') { // no interface set assign default
-            _resolv_get_default_iface(statp->iface, sizeof(statp->iface));
-        }
-
-        pthread_once(&_res_cache_once, _res_cache_init);
-        pthread_mutex_lock(&_res_cache_list_lock);
-        info = _find_cache_info_locked(statp->iface);
-
-        if (info == NULL) {
-            pthread_mutex_unlock(&_res_cache_list_lock);
-            return 0;
-        }
-
         XLOG("_resolv_populate_res_for_iface: %s\n", statp->iface);
         for (nserv = 0; nserv < MAXNS; nserv++) {
             ai = info->nsaddrinfo[nserv];
@@ -2502,8 +2684,6 @@
         while (pp < statp->dnsrch + MAXDNSRCH && *p != -1) {
             *pp++ = &statp->defdname + *p++;
         }
-
-        pthread_mutex_unlock(&_res_cache_list_lock);
     }
-    return nserv;
+    pthread_mutex_unlock(&_res_cache_list_lock);
 }
diff --git a/libc/netbsd/resolv/res_init.c b/libc/netbsd/resolv/res_init.c
index ff65299..ceb412b 100644
--- a/libc/netbsd/resolv/res_init.c
+++ b/libc/netbsd/resolv/res_init.c
@@ -806,4 +806,11 @@
 		}
 	}
 }
+
+void res_setmark(res_state statp, int mark)
+{
+	if (statp != NULL) {
+		statp->_mark = mark;
+	}
+}
 #endif /* ANDROID_CHANGES */
diff --git a/libc/netbsd/resolv/res_send.c b/libc/netbsd/resolv/res_send.c
index 0bb5b6b..f65b015 100644
--- a/libc/netbsd/resolv/res_send.c
+++ b/libc/netbsd/resolv/res_send.c
@@ -762,10 +762,13 @@
 	if (statp->_vcsock >= 0 && (statp->_flags & RES_F_VC) != 0) {
 		struct sockaddr_storage peer;
 		socklen_t size = sizeof peer;
-
+		int old_mark;
+		int mark_size = sizeof(old_mark);
 		if (getpeername(statp->_vcsock,
 				(struct sockaddr *)(void *)&peer, &size) < 0 ||
-		    !sock_eq((struct sockaddr *)(void *)&peer, nsap)) {
+		    !sock_eq((struct sockaddr *)(void *)&peer, nsap) ||
+			getsockopt(statp->_vcsock, SOL_SOCKET, SO_MARK, &old_mark, &mark_size) < 0 ||
+			old_mark != statp->_mark) {
 			res_nclose(statp);
 			statp->_flags &= ~RES_F_VC;
 		}
@@ -795,6 +798,14 @@
 				return (-1);
 			}
 		}
+		if (statp->_mark != 0) {
+			if (setsockopt(statp->_vcsock, SOL_SOCKET,
+				        SO_MARK, &statp->_mark, sizeof(statp->_mark)) < 0) {
+				*terrno = errno;
+				Perror(statp, stderr, "setsockopt", errno);
+				return -1;
+			}
+		}
 		errno = 0;
 		if (random_bind(statp->_vcsock,nsap->sa_family) < 0) {
 			*terrno = errno;
@@ -1070,6 +1081,14 @@
 				return (-1);
 			}
 		}
+
+		if (statp->_mark != 0) {
+			if (setsockopt(EXT(statp).nssocks[ns], SOL_SOCKET,
+					SO_MARK, &(statp->_mark), sizeof(statp->_mark)) < 0) {
+				res_nclose(statp);
+				return -1;
+			}
+		}
 #ifndef CANNOT_CONNECT_DGRAM
 		/*
 		 * On a 4.3BSD+ machine (client and server,
@@ -1097,6 +1116,7 @@
 #endif /* !CANNOT_CONNECT_DGRAM */
 		Dprint(statp->options & RES_DEBUG,
 		       (stdout, ";; new DG socket\n"))
+
 	}
 	s = EXT(statp).nssocks[ns];
 #ifndef CANNOT_CONNECT_DGRAM
diff --git a/libc/private/resolv_cache.h b/libc/private/resolv_cache.h
index d70857d..68a1180 100644
--- a/libc/private/resolv_cache.h
+++ b/libc/private/resolv_cache.h
@@ -28,6 +28,7 @@
 #ifndef _RESOLV_CACHE_H_
 #define _RESOLV_CACHE_H_
 
+#include <stddef.h>
 #include <sys/cdefs.h>
 
 struct __res_state;
@@ -77,16 +78,17 @@
 __LIBC_HIDDEN__
 extern struct in_addr* _resolv_get_addr_of_iface(const char* ifname);
 
-/* Copy the name of the default interface to provided buffer.
- * Return length of buffer on success on failure -1 is returned */
+/* Copy the name of the default interface to the provided buffer.
+ * Returns the string length of the default interface,
+ * be that less or more than the buffLen, or 0 if nothing had been written */
 __LIBC_HIDDEN__
-extern int _resolv_get_default_iface(char* buff, int buffLen);
+ extern size_t _resolv_get_default_iface(char* buff, size_t buffLen);
 
 /* sets the name server addresses to the provided res_state structure. The
  * name servers are retrieved from the cache which is associated
  * with the interface to which the res_state structure is associated */
 __LIBC_HIDDEN__
-extern int _resolv_populate_res_for_iface(struct __res_state* statp);
+extern void _resolv_populate_res_for_iface(struct __res_state* statp);
 
 typedef enum {
     RESOLV_CACHE_UNSUPPORTED,  /* the cache can't handle that kind of queries */
diff --git a/libc/private/resolv_iface.h b/libc/private/resolv_iface.h
index bf5abad..ad42793 100644
--- a/libc/private/resolv_iface.h
+++ b/libc/private/resolv_iface.h
@@ -48,7 +48,7 @@
 extern void _resolv_set_default_iface(const char* ifname);
 
 /* set name servers for an interface */
-extern void _resolv_set_nameservers_for_iface(const char* ifname, char** servers, int numservers,
+extern void _resolv_set_nameservers_for_iface(const char* ifname, const char** servers, int numservers,
         const char *domains);
 
 /* tell resolver of the address of an interface */
@@ -66,6 +66,9 @@
 /* clear pid from being associated with an interface */
 extern void _resolv_clear_iface_for_pid(int pid);
 
+/* clear the entire mapping of pids to interfaces. */
+extern void _resolv_clear_iface_pid_mapping();
+
 /** Gets the name of the interface to which the pid is attached.
  *  On error, -1 is returned.
  *  If no interface is found, 0 is returned and buff is set to empty ('\0').
@@ -75,6 +78,27 @@
  *               buffLen Length of buff. An interface is at most IF_NAMESIZE in length */
 extern int _resolv_get_pids_associated_interface(int pid, char* buff, int buffLen);
 
+
+/** set a uid range to use the name servers of the specified interface
+ *  If [low,high] overlaps with an already existing rule -1 is returned */
+extern int _resolv_set_iface_for_uid_range(const char* ifname, int uid_start, int uid_end);
+
+/* clear a uid range from being associated with an interface
+ * If the range given is not mapped -1 is returned. */
+extern int _resolv_clear_iface_for_uid_range(int uid_start, int uid_end);
+
+/* clear the entire mapping of uid ranges to interfaces. */
+extern void _resolv_clear_iface_uid_range_mapping();
+
+/** Gets the name of the interface to which the uid is attached.
+ *  On error, -1 is returned.
+ *  If no interface is found, 0 is returned and buff is set to empty ('\0').
+ *  If an interface is found, the name is copied to buff and the length of the name is returned.
+ *  Arguments:   uid The uid to find an interface for
+ *               buff A buffer to copy the result to
+ *               buffLen Length of buff. An interface is at most IF_NAMESIZE in length */
+extern int _resolv_get_uids_associated_interface(int uid, char* buff, int buffLen);
+
 #endif /* _BIONIC_RESOLV_IFACE_FUNCTIONS_DECLARED */
 
 __END_DECLS
diff --git a/libc/private/resolv_private.h b/libc/private/resolv_private.h
index 9648a8f..c7bcb89 100644
--- a/libc/private/resolv_private.h
+++ b/libc/private/resolv_private.h
@@ -175,6 +175,7 @@
 	res_send_qhook qhook;		/* query hook */
 	res_send_rhook rhook;		/* response hook */
 	int	res_h_errno;		/* last one set for this context */
+	int _mark;          /* If non-0 SET_MARK to _mark on all request sockets */
 	int	_vcsock;		/* PRIVATE: for res_send VC i/o */
 	u_int	_flags;			/* PRIVATE: see below */
 	u_int	_pad;			/* make _u 64 bit aligned */
@@ -490,6 +491,7 @@
 				    union res_sockaddr_union *, int);
 
 void res_setiface();
+void res_setmark();
 u_int  res_randomid(void);
 
 __END_DECLS
diff --git a/tests/system_properties_test.cpp b/tests/system_properties_test.cpp
index 9602607..b9256c6 100644
--- a/tests/system_properties_test.cpp
+++ b/tests/system_properties_test.cpp
@@ -198,6 +198,84 @@
     ASSERT_EQ((const prop_info *)NULL, __system_property_find_nth(247));
 }
 
+static void hierarchical_test_callback(const prop_info *pi, void *cookie) {
+    bool (*ok)[8][8] = static_cast<bool (*)[8][8]>(cookie);
+
+    char name[PROP_NAME_MAX];
+    char value[PROP_VALUE_MAX];
+
+    __system_property_read(pi, name, value);
+
+    int name_i, name_j, name_k;
+    int value_i, value_j, value_k;
+    ASSERT_EQ(3, sscanf(name, "property_%d.%d.%d", &name_i, &name_j, &name_k));
+    ASSERT_EQ(3, sscanf(value, "value_%d.%d.%d", &value_i, &value_j, &value_k));
+    ASSERT_EQ(name_i, value_i);
+    ASSERT_GE(name_i, 0);
+    ASSERT_LT(name_i, 8);
+    ASSERT_EQ(name_j, value_j);
+    ASSERT_GE(name_j, 0);
+    ASSERT_LT(name_j, 8);
+    ASSERT_EQ(name_k, value_k);
+    ASSERT_GE(name_k, 0);
+    ASSERT_LT(name_k, 8);
+
+    ok[name_i][name_j][name_k] = true;
+}
+
+TEST(properties, fill_hierarchical) {
+    LocalPropertyTestState pa;
+    ASSERT_TRUE(pa.valid);
+    char prop_name[PROP_NAME_MAX];
+    char prop_value[PROP_VALUE_MAX];
+    char prop_value_ret[PROP_VALUE_MAX];
+    int ret;
+
+    for (int i = 0; i < 8; i++) {
+        for (int j = 0; j < 8; j++) {
+            for (int k = 0; k < 8; k++) {
+                ret = snprintf(prop_name, PROP_NAME_MAX - 1, "property_%d.%d.%d", i, j, k);
+                memset(prop_name + ret, 'a', PROP_NAME_MAX - 1 - ret);
+                ret = snprintf(prop_value, PROP_VALUE_MAX - 1, "value_%d.%d.%d", i, j, k);
+                memset(prop_value + ret, 'b', PROP_VALUE_MAX - 1 - ret);
+                prop_name[PROP_NAME_MAX - 1] = 0;
+                prop_value[PROP_VALUE_MAX - 1] = 0;
+
+                ASSERT_EQ(0, __system_property_add(prop_name, PROP_NAME_MAX - 1, prop_value, PROP_VALUE_MAX - 1));
+            }
+        }
+    }
+
+    for (int i = 0; i < 8; i++) {
+        for (int j = 0; j < 8; j++) {
+            for (int k = 0; k < 8; k++) {
+                ret = snprintf(prop_name, PROP_NAME_MAX - 1, "property_%d.%d.%d", i, j, k);
+                memset(prop_name + ret, 'a', PROP_NAME_MAX - 1 - ret);
+                ret = snprintf(prop_value, PROP_VALUE_MAX - 1, "value_%d.%d.%d", i, j, k);
+                memset(prop_value + ret, 'b', PROP_VALUE_MAX - 1 - ret);
+                prop_name[PROP_NAME_MAX - 1] = 0;
+                prop_value[PROP_VALUE_MAX - 1] = 0;
+                memset(prop_value_ret, '\0', PROP_VALUE_MAX);
+
+                ASSERT_EQ(PROP_VALUE_MAX - 1, __system_property_get(prop_name, prop_value_ret));
+                ASSERT_EQ(0, memcmp(prop_value, prop_value_ret, PROP_VALUE_MAX));
+            }
+        }
+    }
+
+    bool ok[8][8][8];
+    memset(ok, 0, sizeof(ok));
+    __system_property_foreach(hierarchical_test_callback, ok);
+
+    for (int i = 0; i < 8; i++) {
+        for (int j = 0; j < 8; j++) {
+            for (int k = 0; k < 8; k++) {
+                ASSERT_TRUE(ok[i][j][k]);
+            }
+        }
+    }
+}
+
 TEST(properties, errors) {
     LocalPropertyTestState pa;
     ASSERT_TRUE(pa.valid);