1 files changed, 24 insertions, 2 deletions

diff --git a/lib/libc/net/getnameinfo.c b/lib/libc/net/getnameinfo.c
index cee07f6e0fe7..9f60ae30910c 100644
--- a/lib/libc/net/getnameinfo.c
+++ b/lib/libc/net/getnameinfo.c
@@ -46,6 +46,7 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include "namespace.h"
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <net/if.h>
@@ -53,10 +54,12 @@ __FBSDID("$FreeBSD$");
 #include <arpa/inet.h>
 #include <arpa/nameser.h>
 #include <netdb.h>
+#include <pthread.h>
 #include <resolv.h>
 #include <string.h>
 #include <stddef.h>
 #include <errno.h>
+#include "un-namespace.h"
 
 static const struct afd {
 	int a_af;
@@ -85,6 +88,19 @@ static int ip6_parsenumeric(const struct sockaddr *, const char *, char *,
 static int ip6_sa2str(const struct sockaddr_in6 *, char *, size_t, int);
 #endif
 
+/*
+ * XXX: Many dependencies are not thread-safe.  So, we share lock between
+ * getaddrinfo() and getipnodeby*().  Still, we cannot use
+ * getaddrinfo() and getipnodeby*() in conjunction with other
+ * functions which call them.
+ */
+#include "libc_private.h"
+extern pthread_mutex_t __getaddrinfo_thread_lock;
+#define THREAD_LOCK() \
+	if (__isthreaded) _pthread_mutex_lock(&__getaddrinfo_thread_lock);
+#define THREAD_UNLOCK() \
+	if (__isthreaded) _pthread_mutex_unlock(&__getaddrinfo_thread_lock);
+
 int
 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 	const struct sockaddr *sa;
@@ -136,6 +152,7 @@ getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 		 * servlen == 0 means that the caller does not want the result.
 		 */
 	} else {
+		THREAD_LOCK();
 		if (flags & NI_NUMERICSERV)
 			sp = NULL;
 		else {
@@ -143,15 +160,20 @@ getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 				(flags & NI_DGRAM) ? "udp" : "tcp");
 		}
 		if (sp) {
-			if (strlen(sp->s_name) + 1 > servlen)
+			if (strlen(sp->s_name) + 1 > servlen) {
+				THREAD_UNLOCK();
 				return EAI_MEMORY;
+			}
 			strlcpy(serv, sp->s_name, servlen);
 		} else {
 			snprintf(numserv, sizeof(numserv), "%u", ntohs(port));
-			if (strlen(numserv) + 1 > servlen)
+			if (strlen(numserv) + 1 > servlen) {
+				THREAD_UNLOCK();
 				return EAI_MEMORY;
+			}
 			strlcpy(serv, numserv, servlen);
 		}
+		THREAD_UNLOCK();
 	}
 
 	switch (sa->sa_family) {