Fix the gethostbyname memory leak

2 files changed, 652 insertions, 0 deletions

diff --git a/recipes-core/eglibc/eglibc_%.bbappend b/recipes-core/eglibc/eglibc_%.bbappend
new file mode 100644
index 0000000..ece3df9
--- /dev/null
+++ b/recipes-core/eglibc/eglibc_%.bbappend
@@ -0,0 +1,4 @@
+SRC_URI += " file://cvs-gethostbyname4-memory-leak.patch \
+           "
+
+FILESEXTRAPATHS_prepend := "${THISDIR}/files"
diff --git a/recipes-core/eglibc/files/cvs-gethostbyname4-memory-leak.patch b/recipes-core/eglibc/files/cvs-gethostbyname4-memory-leak.patch
new file mode 100644
index 0000000..3b66a60
--- /dev/null
+++ b/recipes-core/eglibc/files/cvs-gethostbyname4-memory-leak.patch
@@ -0,0 +1,648 @@
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/include/arpa/nameser_compat.h libc/include/arpa/nameser_compat.h
+--- libc.orig/include/arpa/nameser_compat.h	2008-05-12 11:38:35.000000000 -0400
++++ libc/include/arpa/nameser_compat.h	2017-04-06 16:34:20.413823000 -0400
+@@ -1,8 +1,8 @@
+ #ifndef _ARPA_NAMESER_COMPAT_
+ #include <resolv/arpa/nameser_compat.h>
+ 
+-/* Picksome unused number to represent lookups of IPv4 and IPv6 (i.e.,
+-   T_A and T_AAAA).  */
+-#define T_UNSPEC 62321
++/* The number is outside the 16-bit RR type range and is used
++   internally by the implementation.  */
++#define T_QUERY_A_AND_AAAA 439963904
+ 
+ #endif
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/include/resolv.h libc/include/resolv.h
+--- libc.orig/include/resolv.h	2013-09-05 18:41:05.000000000 -0400
++++ libc/include/resolv.h	2017-04-06 16:33:09.853700600 -0400
+@@ -48,11 +48,11 @@
+ libc_hidden_proto (__res_state)
+ 
+ int __libc_res_nquery (res_state, const char *, int, int, u_char *, int,
+-		       u_char **, u_char **, int *, int *);
++		       u_char **, u_char **, int *, int *, int *);
+ int __libc_res_nsearch (res_state, const char *, int, int, u_char *, int,
+-			u_char **, u_char **, int *, int *);
++			u_char **, u_char **, int *, int *, int *);
+ int __libc_res_nsend (res_state, const u_char *, int, const u_char *, int,
+-		      u_char *, int, u_char **, u_char **, int *, int *)
++		      u_char *, int, u_char **, u_char **, int *, int *, int *)
+   attribute_hidden;
+ 
+ libresolv_hidden_proto (_sethtent)
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/gethnamaddr.c libc/resolv/gethnamaddr.c
+--- libc.orig/resolv/gethnamaddr.c	2013-06-15 13:37:04.000000000 -0400
++++ libc/resolv/gethnamaddr.c	2017-04-06 16:13:44.727609300 -0400
+@@ -621,7 +621,7 @@
+ 	buf.buf = origbuf = (querybuf *) alloca (1024);
+ 
+ 	if ((n = __libc_res_nsearch(&_res, name, C_IN, type, buf.buf->buf, 1024,
+-				    &buf.ptr, NULL, NULL, NULL)) < 0) {
++				    &buf.ptr, NULL, NULL, NULL, NULL)) < 0) {
+ 		if (buf.buf != origbuf)
+ 			free (buf.buf);
+ 		Dprintf("res_nsearch failed (%d)\n", n);
+@@ -716,12 +716,12 @@
+ 	buf.buf = orig_buf = (querybuf *) alloca (1024);
+ 
+ 	n = __libc_res_nquery(&_res, qbuf, C_IN, T_PTR, buf.buf->buf, 1024,
+-			      &buf.ptr, NULL, NULL, NULL);
++			      &buf.ptr, NULL, NULL, NULL, NULL);
+ 	if (n < 0 && af == AF_INET6 && (_res.options & RES_NOIP6DOTINT) == 0) {
+ 		strcpy(qp, "ip6.int");
+ 		n = __libc_res_nquery(&_res, qbuf, C_IN, T_PTR, buf.buf->buf,
+ 				      buf.buf != orig_buf ? MAXPACKET : 1024,
+-				      &buf.ptr, NULL, NULL, NULL);
++				      &buf.ptr, NULL, NULL, NULL, NULL);
+ 	}
+ 	if (n < 0) {
+ 		if (buf.buf != orig_buf)
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/nss_dns/dns-canon.c libc/resolv/nss_dns/dns-canon.c
+--- libc.orig/resolv/nss_dns/dns-canon.c	2014-01-03 12:51:28.000000000 -0500
++++ libc/resolv/nss_dns/dns-canon.c	2017-04-06 16:11:49.654787500 -0400
+@@ -62,7 +62,7 @@
+     {
+       int r = __libc_res_nquery (&_res, name, ns_c_in, qtypes[i],
+ 				 buf, sizeof (buf), &ansp.ptr, NULL, NULL,
+-				 NULL);
++				 NULL, NULL);
+       if (r > 0)
+ 	{
+ 	  /* We need to decode the response.  Just one question record.
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/nss_dns/dns-host.c libc/resolv/nss_dns/dns-host.c
+--- libc.orig/resolv/nss_dns/dns-host.c	2017-04-06 14:03:55.000000000 -0400
++++ libc/resolv/nss_dns/dns-host.c	2017-04-06 16:12:50.319551700 -0400
+@@ -190,7 +190,7 @@
+   host_buffer.buf = orig_host_buffer = (querybuf *) alloca (1024);
+ 
+   n = __libc_res_nsearch (&_res, name, C_IN, type, host_buffer.buf->buf,
+-			  1024, &host_buffer.ptr, NULL, NULL, NULL);
++			  1024, &host_buffer.ptr, NULL, NULL, NULL, NULL);
+   if (n < 0)
+     {
+       switch (errno)
+@@ -225,7 +225,7 @@
+ 	n = __libc_res_nsearch (&_res, name, C_IN, T_A, host_buffer.buf->buf,
+ 				host_buffer.buf != orig_host_buffer
+ 				? MAXPACKET : 1024, &host_buffer.ptr,
+-				NULL, NULL, NULL);
++				NULL, NULL, NULL, NULL);
+ 
+       if (n < 0)
+ 	{
+@@ -308,12 +308,13 @@
+   u_char *ans2p = NULL;
+   int nans2p = 0;
+   int resplen2 = 0;
++  int ans2p_malloced = 0;
+ 
+   int olderr = errno;
+   enum nss_status status;
+-  int n = __libc_res_nsearch (&_res, name, C_IN, T_UNSPEC,
++  int n = __libc_res_nsearch (&_res, name, C_IN, T_QUERY_A_AND_AAAA,
+ 			      host_buffer.buf->buf, 2048, &host_buffer.ptr,
+-			      &ans2p, &nans2p, &resplen2);
++			      &ans2p, &nans2p, &resplen2, &ans2p_malloced);
+   if (n < 0)
+     {
+       switch (errno)
+@@ -352,6 +353,10 @@
+ 			  resplen2, name, pat, buffer, buflen,
+ 			  errnop, herrnop, ttlp);
+ 
++  /* Check whether ans2p was separately allocated.  */
++  if (ans2p_malloced)
++    free (ans2p);
++
+   if (host_buffer.buf != orig_host_buffer)
+     free (host_buffer.buf);
+ 
+@@ -460,7 +465,7 @@
+ 	  strcpy (qp, "].ip6.arpa");
+ 	  n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR,
+ 				 host_buffer.buf->buf, 1024, &host_buffer.ptr,
+-				 NULL, NULL, NULL);
++				 NULL, NULL, NULL, NULL);
+ 	  if (n >= 0)
+ 	    goto got_it_already;
+ 	}
+@@ -481,14 +486,14 @@
+     }
+ 
+   n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer.buf->buf,
+-			 1024, &host_buffer.ptr, NULL, NULL, NULL);
++			 1024, &host_buffer.ptr, NULL, NULL, NULL, NULL);
+   if (n < 0 && af == AF_INET6 && (_res.options & RES_NOIP6DOTINT) == 0)
+     {
+       strcpy (qp, "ip6.int");
+       n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer.buf->buf,
+ 			     host_buffer.buf != orig_host_buffer
+ 			     ? MAXPACKET : 1024, &host_buffer.ptr,
+-			     NULL, NULL, NULL);
++			     NULL, NULL, NULL, NULL);
+     }
+   if (n < 0)
+     {
+@@ -613,7 +618,8 @@
+   int have_to_map = 0;
+   uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct host_data);
+   buffer += pad;
+-  if (__builtin_expect (buflen < sizeof (struct host_data) + pad, 0))
++  buflen = buflen > pad ? buflen - pad : 0;
++  if (__glibc_unlikely (buflen < sizeof (struct host_data)))
+     {
+       /* The buffer is too small.  */
+     too_small:
+@@ -1267,8 +1273,8 @@
+      expected application behaviour.  Some of the synthesized responses
+      aren't very well thought out and sometimes appear to imply that
+      IPv4 responses are always answer 1, and IPv6 responses are always
+-     answer 2, but that's not true (see the implementation of send_dg
+-     and send_vc to see response can arrive in any order, particularly
++     answer 2, but that's not true (see the implemetnation of send_dg
++     and send_vc to see response can arrive in any order, particlarly
+      for UDP). However, we expect it holds roughly enough of the time
+      that this code works, but certainly needs to be fixed to make this
+      a more robust implementation.
+@@ -1305,12 +1311,12 @@
+      ----------------------------------------------
+ 
+      [1] If the first response is a success we return success.
+-	 This ignores the state of the second answer and in fact
+-	 incorrectly sets errno and h_errno to that of the second
++         This ignores the state of the second answer and in fact
++         incorrectly sets errno and h_errno to that of the second
+ 	 answer.  However because the response is a success we ignore
+ 	 *errnop and *h_errnop (though that means you touched errno on
+-	 success).  We are being conservative here and returning the
+-	 likely IPv4 response in the first answer as a success.
++         success).  We are being conservative here and returning the
++         likely IPv4 response in the first answer as a success.
+ 
+      [2] If the first response is a recoverable TRYAGAIN we return
+ 	 that instead of looking at the second response.  The
+@@ -1364,7 +1370,7 @@
+       if (status != NSS_STATUS_SUCCESS && status2 != NSS_STATUS_NOTFOUND)
+ 	status = status2;
+       /* Do not return a truncated second response (unless it was
+-	 unavoidable e.g. unrecoverable TRYAGAIN).  */
++         unavoidable e.g. unrecoverable TRYAGAIN).  */
+       if (status == NSS_STATUS_SUCCESS
+ 	  && (status2 == NSS_STATUS_TRYAGAIN
+ 	      && *errnop == ERANGE && *h_errnop != NO_RECOVERY))
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/nss_dns/dns-network.c libc/resolv/nss_dns/dns-network.c
+--- libc.orig/resolv/nss_dns/dns-network.c	2014-01-03 12:51:28.000000000 -0500
++++ libc/resolv/nss_dns/dns-network.c	2017-04-06 16:13:18.561373600 -0400
+@@ -118,18 +118,15 @@
+   } net_buffer;
+   querybuf *orig_net_buffer;
+   int anslen;
+-  char *qbuf;
+   enum nss_status status;
+ 
+   if (__res_maybe_init (&_res, 0) == -1)
+     return NSS_STATUS_UNAVAIL;
+ 
+-  qbuf = strdupa (name);
+-
+   net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
+ 
+-  anslen = __libc_res_nsearch (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
+-			       1024, &net_buffer.ptr, NULL, NULL, NULL);
++  anslen = __libc_res_nsearch (&_res, name, C_IN, T_PTR, net_buffer.buf->buf,
++			       1024, &net_buffer.ptr, NULL, NULL, NULL, NULL);
+   if (anslen < 0)
+     {
+       /* Nothing found.  */
+@@ -205,7 +202,7 @@
+   net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
+ 
+   anslen = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
+-			      1024, &net_buffer.ptr, NULL, NULL, NULL);
++			      1024, &net_buffer.ptr, NULL, NULL, NULL, NULL);
+   if (anslen < 0)
+     {
+       /* Nothing found.  */
+@@ -398,8 +395,8 @@
+ 
+ 	case BYNAME:
+ 	  {
+-	    char **ap = result->n_aliases++;
+-	    while (*ap != NULL)
++	    char **ap;
++	    for (ap = result->n_aliases; *ap != NULL; ++ap)
+ 	      {
+ 		/* Check each alias name for being of the forms:
+ 		   4.3.2.1.in-addr.arpa		= net 1.2.3.4
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/res_mkquery.c libc/resolv/res_mkquery.c
+--- libc.orig/resolv/res_mkquery.c	2013-09-05 18:41:05.000000000 -0400
++++ libc/resolv/res_mkquery.c	2017-04-06 16:13:56.412597600 -0400
+@@ -110,6 +110,10 @@
+ 	int n;
+ 	u_char *dnptrs[20], **dpp, **lastdnptr;
+ 
++	if (class < 0 || class > 65535
++	    || type < 0 || type > 65535)
++	  return -1;
++
+ #ifdef DEBUG
+ 	if (statp->options & RES_DEBUG)
+ 		printf(";; res_nmkquery(%s, %s, %s, %s)\n",
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/res_query.c libc/resolv/res_query.c
+--- libc.orig/resolv/res_query.c	2017-04-06 14:03:55.000000000 -0400
++++ libc/resolv/res_query.c	2017-04-06 16:15:04.137842200 -0400
+@@ -98,7 +98,7 @@
+ __libc_res_nquerydomain(res_state statp, const char *name, const char *domain,
+ 			int class, int type, u_char *answer, int anslen,
+ 			u_char **answerp, u_char **answerp2, int *nanswerp2,
+-			int *resplen2);
++			int *resplen2, int *answerp2_malloced);
+ 
+ /*
+  * Formulate a normal query, send, and await answer.
+@@ -119,14 +119,15 @@
+ 		  u_char **answerp,	/* if buffer needs to be enlarged */
+ 		  u_char **answerp2,
+ 		  int *nanswerp2,
+-		  int *resplen2)
++		  int *resplen2,
++		  int *answerp2_malloced)
+ {
+ 	HEADER *hp = (HEADER *) answer;
+ 	HEADER *hp2;
+ 	int n, use_malloc = 0;
+ 	u_int oflags = statp->_flags;
+ 
+-	size_t bufsize = (type == T_UNSPEC ? 2 : 1) * QUERYSIZE;
++	size_t bufsize = (type == T_QUERY_A_AND_AAAA ? 2 : 1) * QUERYSIZE;
+ 	u_char *buf = alloca (bufsize);
+ 	u_char *query1 = buf;
+ 	int nquery1 = -1;
+@@ -141,7 +142,7 @@
+ 		printf(";; res_query(%s, %d, %d)\n", name, class, type);
+ #endif
+ 
+-	if (type == T_UNSPEC)
++	if (type == T_QUERY_A_AND_AAAA)
+ 	  {
+ 	    n = res_nmkquery(statp, QUERY, name, class, T_A, NULL, 0, NULL,
+ 			     query1, bufsize);
+@@ -194,7 +195,7 @@
+ 	if (__builtin_expect (n <= 0, 0) && !use_malloc) {
+ 		/* Retry just in case res_nmkquery failed because of too
+ 		   short buffer.  Shouldn't happen.  */
+-		bufsize = (type == T_UNSPEC ? 2 : 1) * MAXPACKET;
++		bufsize = (type == T_QUERY_A_AND_AAAA ? 2 : 1) * MAXPACKET;
+ 		buf = malloc (bufsize);
+ 		if (buf != NULL) {
+ 			query1 = buf;
+@@ -224,7 +225,8 @@
+ 	}
+ 	assert (answerp == NULL || (void *) *answerp == (void *) answer);
+ 	n = __libc_res_nsend(statp, query1, nquery1, query2, nquery2, answer,
+-			     anslen, answerp, answerp2, nanswerp2, resplen2);
++			     anslen, answerp, answerp2, nanswerp2, resplen2,
++			     answerp2_malloced);
+ 	if (use_malloc)
+ 		free (buf);
+ 	if (n < 0) {
+@@ -316,7 +318,7 @@
+ 	   int anslen)		/* size of answer buffer */
+ {
+ 	return __libc_res_nquery(statp, name, class, type, answer, anslen,
+-				 NULL, NULL, NULL, NULL);
++				 NULL, NULL, NULL, NULL, NULL);
+ }
+ libresolv_hidden_def (res_nquery)
+ 
+@@ -335,7 +337,8 @@
+ 		   u_char **answerp,
+ 		   u_char **answerp2,
+ 		   int *nanswerp2,
+-		   int *resplen2)
++		   int *resplen2,
++		   int *answerp2_malloced)
+ {
+ 	const char *cp, * const *domain;
+ 	HEADER *hp = (HEADER *) answer;
+@@ -360,7 +363,7 @@
+ 	if (!dots && (cp = res_hostalias(statp, name, tmp, sizeof tmp))!= NULL)
+ 		return (__libc_res_nquery(statp, cp, class, type, answer,
+ 					  anslen, answerp, answerp2,
+-					  nanswerp2, resplen2));
++					  nanswerp2, resplen2, answerp2_malloced));
+ 
+ #ifdef DEBUG
+ 	if (statp->options & RES_DEBUG)
+@@ -377,8 +380,9 @@
+ 	if (dots >= statp->ndots || trailing_dot) {
+ 		ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
+ 					      answer, anslen, answerp,
+-					      answerp2, nanswerp2, resplen2);
+-		if (ret > 0 || trailing_dot)
++					      answerp2, nanswerp2, resplen2,
++					      answerp2_malloced);
++		if (ret > 0 || (ret == 0 && *resplen2 > 0) || trailing_dot)
+ 			return (ret);
+ 		saved_herrno = h_errno;
+ 		tried_as_is++;
+@@ -386,12 +390,12 @@
+ 			answer = *answerp;
+ 			anslen = MAXPACKET;
+ 		}
+-		if (answerp2
+-		    && (*answerp2 < answer || *answerp2 >= answer + anslen))
++		if (answerp2 && *answerp2_malloced)
+ 		  {
+ 		    free (*answerp2);
+ 		    *answerp2 = NULL;
+ 		    *nanswerp2 = 0;
++		    *answerp2_malloced = 0;
+ 		  }
+ 	}
+ 
+@@ -418,21 +422,20 @@
+ 						      class, type,
+ 						      answer, anslen, answerp,
+ 						      answerp2, nanswerp2,
+-						      resplen2);
+-			if (ret > 0)
++						      resplen2, answerp2_malloced);
++			if ((ret > 0) || (ret == 0 && *resplen2 > 0))
+ 				return (ret);
+ 
+ 			if (answerp && *answerp != answer) {
+ 				answer = *answerp;
+ 				anslen = MAXPACKET;
+ 			}
+-			if (answerp2
+-			    && (*answerp2 < answer
+-				|| *answerp2 >= answer + anslen))
++			if (answerp2 && *answerp2_malloced)
+ 			  {
+ 			    free (*answerp2);
+ 			    *answerp2 = NULL;
+ 			    *nanswerp2 = 0;
++			    *answerp2_malloced = 0;
+ 			  }
+ 
+ 			/*
+@@ -488,8 +491,9 @@
+ 	    && !(tried_as_is || root_on_list)) {
+ 		ret = __libc_res_nquerydomain(statp, name, NULL, class, type,
+ 					      answer, anslen, answerp,
+-					      answerp2, nanswerp2, resplen2);
+-		if (ret > 0)
++					      answerp2, nanswerp2, resplen2,
++					      answerp2_malloced);
++		if ((ret > 0) || (ret == 0 && *resplen2 > 0))
+ 			return (ret);
+ 	}
+ 
+@@ -500,11 +504,12 @@
+ 	 * else send back meaningless H_ERRNO, that being the one from
+ 	 * the last DNSRCH we did.
+ 	 */
+-	if (answerp2 && (*answerp2 < answer || *answerp2 >= answer + anslen))
++	if (answerp2 && *answerp2_malloced)
+ 	  {
+ 	    free (*answerp2);
+ 	    *answerp2 = NULL;
+ 	    *nanswerp2 = 0;
++	    *answerp2_malloced = 0;
+ 	  }
+ 	if (saved_herrno != -1)
+ 		RES_SET_H_ERRNO(statp, saved_herrno);
+@@ -524,7 +529,7 @@
+ 	    int anslen)		/* size of answer */
+ {
+ 	return __libc_res_nsearch(statp, name, class, type, answer,
+-				  anslen, NULL, NULL, NULL, NULL);
++				  anslen, NULL, NULL, NULL, NULL, NULL);
+ }
+ libresolv_hidden_def (res_nsearch)
+ 
+@@ -542,7 +547,8 @@
+ 			u_char **answerp,
+ 			u_char **answerp2,
+ 			int *nanswerp2,
+-			int *resplen2)
++			int *resplen2,
++			int *answerp2_malloced)
+ {
+ 	char nbuf[MAXDNAME];
+ 	const char *longname = nbuf;
+@@ -584,7 +590,7 @@
+ 	}
+ 	return (__libc_res_nquery(statp, longname, class, type, answer,
+ 				  anslen, answerp, answerp2, nanswerp2,
+-				  resplen2));
++				  resplen2, answerp2_malloced));
+ }
+ 
+ int
+@@ -596,7 +602,8 @@
+ 	    int anslen)		/* size of answer */
+ {
+ 	return __libc_res_nquerydomain(statp, name, domain, class, type,
+-				       answer, anslen, NULL, NULL, NULL, NULL);
++				       answer, anslen, NULL, NULL, NULL, NULL,
++				       NULL);
+ }
+ libresolv_hidden_def (res_nquerydomain)
+ 
+diff -Naur '--exclude=.git' '--exclude=*.pyc' '--exclude=*.py' '--exclude=*.*~' libc.orig/resolv/res_send.c libc/resolv/res_send.c
+--- libc.orig/resolv/res_send.c	2017-04-06 14:03:55.000000000 -0400
++++ libc/resolv/res_send.c	2017-04-06 16:16:12.448561400 -0400
+@@ -120,13 +120,13 @@
+ #define MAXPACKET       65536
+ #endif
+ 
+-
++#ifdef SOCK_NONBLOCK
+ #ifndef __ASSUME_SOCK_CLOEXEC
+ static int __have_o_nonblock;
+ #else
+ # define __have_o_nonblock 0
+ #endif
+-
++#endif
+ 
+ /* From ev_streams.c.  */
+ 
+@@ -203,12 +203,12 @@
+ static int		send_vc(res_state, const u_char *, int,
+ 				const u_char *, int,
+ 				u_char **, int *, int *, int, u_char **,
+-				u_char **, int *, int *);
++				u_char **, int *, int *, int *);
+ static int		send_dg(res_state, const u_char *, int,
+ 				const u_char *, int,
+ 				u_char **, int *, int *, int,
+ 				int *, int *, u_char **,
+-				u_char **, int *, int *);
++				u_char **, int *, int *, int *);
+ #ifdef DEBUG
+ static void		Aerror(const res_state, FILE *, const char *, int,
+ 			       const struct sockaddr *);
+@@ -360,7 +360,7 @@
+ __libc_res_nsend(res_state statp, const u_char *buf, int buflen,
+ 		 const u_char *buf2, int buflen2,
+ 		 u_char *ans, int anssiz, u_char **ansp, u_char **ansp2,
+-		 int *nansp2, int *resplen2)
++		 int *nansp2, int *resplen2, int *ansp2_malloced)
+ {
+   int gotsomewhere, terrno, try, v_circuit, resplen, ns, n;
+ 
+@@ -565,7 +565,8 @@
+ 			try = statp->retry;
+ 			n = send_vc(statp, buf, buflen, buf2, buflen2,
+ 				    &ans, &anssiz, &terrno,
+-				    ns, ansp, ansp2, nansp2, resplen2);
++				    ns, ansp, ansp2, nansp2, resplen2,
++				    ansp2_malloced);
+ 			if (n < 0)
+ 				return (-1);
+ 			if (n == 0 && (buf2 == NULL || *resplen2 == 0))
+@@ -575,7 +576,7 @@
+ 			n = send_dg(statp, buf, buflen, buf2, buflen2,
+ 				    &ans, &anssiz, &terrno,
+ 				    ns, &v_circuit, &gotsomewhere, ansp,
+-				    ansp2, nansp2, resplen2);
++				    ansp2, nansp2, resplen2, ansp2_malloced);
+ 			if (n < 0)
+ 				return (-1);
+ 			if (n == 0 && (buf2 == NULL || *resplen2 == 0))
+@@ -665,7 +666,7 @@
+ 	  const u_char *buf, int buflen, u_char *ans, int anssiz)
+ {
+   return __libc_res_nsend(statp, buf, buflen, NULL, 0, ans, anssiz,
+-			  NULL, NULL, NULL, NULL);
++			  NULL, NULL, NULL, NULL, NULL);
+ }
+ libresolv_hidden_def (res_nsend)
+ 
+@@ -709,7 +710,7 @@
+    are needed but ANSCP is NULL, then as much of the response as
+    possible is read into the buffer, but the results will be truncated.
+    When truncation happens because of a small answer buffer the DNS
+-   packets header field TC will bet set to 1, indicating a truncated
++   packets header feild TC will bet set to 1, indicating a truncated
+    message and the rest of the socket data will be read and discarded.
+ 
+    Answers to the query are stored secondly in *ANSP2 up to a max of
+@@ -747,7 +748,7 @@
+ 	const u_char *buf, int buflen, const u_char *buf2, int buflen2,
+ 	u_char **ansp, int *anssizp,
+ 	int *terrno, int ns, u_char **anscp, u_char **ansp2, int *anssizp2,
+-	int *resplen2)
++	int *resplen2, int *ansp2_malloced)
+ {
+ 	const HEADER *hp = (HEADER *) buf;
+ 	const HEADER *hp2 = (HEADER *) buf2;
+@@ -828,7 +829,7 @@
+ 	 */
+ 	int recvresp1 = 0;
+ 	/* Skip the second response if there is no second query.
+-	   To do that we mark the second response as received.  */
++           To do that we mark the second response as received.  */
+ 	int recvresp2 = buf2 == NULL;
+ 	uint16_t rlen16;
+  read_len:
+@@ -896,6 +897,8 @@
+ 			}
+ 			*thisanssizp = MAXPACKET;
+ 			*thisansp = newp;
++			if (thisansp == ansp2)
++			  *ansp2_malloced = 1;
+ 			anhp = (HEADER *) newp;
+ 			/* A uint16_t can't be larger than MAXPACKET
+ 			   thus it's safe to allocate MAXPACKET but
+@@ -993,6 +996,7 @@
+ 
+ 		/* only try IPv6 if IPv6 NS and if not failed before */
+ 		if (nsap->sa_family == AF_INET6 && !statp->ipv6_unavail) {
++#ifdef SOCK_NONBLOCK
+ 			if (__builtin_expect (__have_o_nonblock >= 0, 1)) {
+ 				EXT(statp).nssocks[ns] =
+ 				  socket(PF_INET6, SOCK_DGRAM|SOCK_NONBLOCK,
+@@ -1005,12 +1009,14 @@
+ #endif
+ 			}
+ 			if (__builtin_expect (__have_o_nonblock < 0, 0))
++#endif
+ 				EXT(statp).nssocks[ns] =
+ 				  socket(PF_INET6, SOCK_DGRAM, 0);
+ 			if (EXT(statp).nssocks[ns] < 0)
+ 			    statp->ipv6_unavail = errno == EAFNOSUPPORT;
+ 			slen = sizeof (struct sockaddr_in6);
+ 		} else if (nsap->sa_family == AF_INET) {
++#ifdef SOCK_NONBLOCK
+ 			if (__builtin_expect (__have_o_nonblock >= 0, 1)) {
+ 				EXT(statp).nssocks[ns]
+ 				  = socket(PF_INET, SOCK_DGRAM|SOCK_NONBLOCK,
+@@ -1023,6 +1029,7 @@
+ #endif
+ 			}
+ 			if (__builtin_expect (__have_o_nonblock < 0, 0))
++#endif
+ 				EXT(statp).nssocks[ns]
+ 				  = socket(PF_INET, SOCK_DGRAM, 0);
+ 			slen = sizeof (struct sockaddr_in);
+@@ -1049,7 +1056,11 @@
+ 			__res_iclose(statp, false);
+ 			return (0);
+ 		}
++#ifdef SOCK_NONBLOCK
+ 		if (__builtin_expect (__have_o_nonblock < 0, 0)) {
++#else
++                {
++#endif
+ 			/* Make socket non-blocking.  */
+ 			int fl = __fcntl (EXT(statp).nssocks[ns], F_GETFL);
+ 			if  (fl != -1)
+@@ -1083,7 +1094,7 @@
+    are needed but ANSCP is NULL, then as much of the response as
+    possible is read into the buffer, but the results will be truncated.
+    When truncation happens because of a small answer buffer the DNS
+-   packets header field TC will bet set to 1, indicating a truncated
++   packets header feild TC will bet set to 1, indicating a truncated
+    message, while the rest of the UDP packet is discarded.
+ 
+    Answers to the query are stored secondly in *ANSP2 up to a max of
+@@ -1128,7 +1139,7 @@
+ 	const u_char *buf, int buflen, const u_char *buf2, int buflen2,
+ 	u_char **ansp, int *anssizp,
+ 	int *terrno, int ns, int *v_circuit, int *gotsomewhere, u_char **anscp,
+-	u_char **ansp2, int *anssizp2, int *resplen2)
++	u_char **ansp2, int *anssizp2, int *resplen2, int *ansp2_malloced)
+ {
+ 	const HEADER *hp = (HEADER *) buf;
+ 	const HEADER *hp2 = (HEADER *) buf2;
+@@ -1165,7 +1176,7 @@
+ 	int nwritten = 0;
+ 	int recvresp1 = 0;
+ 	/* Skip the second response if there is no second query.
+-	   To do that we mark the second response as received.  */
++           To do that we mark the second response as received.  */
+ 	int recvresp2 = buf2 == NULL;
+ 	pfd[0].fd = EXT(statp).nssocks[ns];
+ 	pfd[0].events = POLLOUT;
+@@ -1359,6 +1370,8 @@
+ 			if (newp != NULL) {
+ 				*thisanssizp = MAXPACKET;
+ 				*thisansp = newp;
++				if (thisansp == ansp2)
++				  *ansp2_malloced = 1;
+ 			}
+ 		}
+ 		/* We could end up with truncation if anscp was NULL
+@@ -1542,6 +1555,7 @@
+ 					retval = reopen (statp, terrno, ns);
+ 					if (retval <= 0)
+ 						return retval;
++					pfd[0].fd = EXT(statp).nssocks[ns];
+ 				}
+ 			}
+ 			goto wait;