diff --git a/include/fileutils.h b/include/fileutils.h
index 479ad15cf..2766b0d43 100644
--- a/include/fileutils.h
+++ b/include/fileutils.h
@@ -74,4 +74,6 @@ static inline struct dirent *xreaddir(DIR *dp)
 
 extern void close_all_fds(const int exclude[], size_t exsz);
 
+int ul_copy_file(int from, int to);
+
 #endif /* UTIL_LINUX_FILEUTILS */
diff --git a/lib/fileutils.c b/lib/fileutils.c
index 003f890f9..9e0823d30 100644
--- a/lib/fileutils.c
+++ b/lib/fileutils.c
@@ -10,6 +10,7 @@
 #include <unistd.h>
 #include <sys/time.h>
 #include <sys/resource.h>
+#include <string.h>
 
 #include "c.h"
 #include "fileutils.h"
@@ -246,3 +247,21 @@ char *stripoff_last_component(char *path)
 	*p = '\0';
 	return p + 1;
 }
+
+/* Copies the contents of a file. Returns -1 on read error, -2 on write error. */
+int ul_copy_file(int from, int to)
+{
+	ssize_t nr, nw, off;
+	char buf[8 * 1024];
+
+	while ((nr = read(from, buf, sizeof(buf))) > 0)
+		for (off = 0; nr > 0; nr -= nw, off += nw)
+			if ((nw = write(to, buf + off, nr)) < 0)
+				return -2;
+	if (nr < 0)
+		return -1;
+#ifdef HAVE_EXPLICIT_BZERO
+	explicit_bzero(buf, sizeof(buf));
+#endif
+	return 0;
+}
diff --git a/login-utils/vipw.c b/login-utils/vipw.c
index 38953b7f5..a107259ae 100644
--- a/login-utils/vipw.c
+++ b/login-utils/vipw.c
@@ -88,23 +88,6 @@ static char *tmp_file;			/* tmp file */
 
 void pw_error (char *, int, int);
 
-static void copyfile(int from, int to)
-{
-	int nr, nw, off;
-	char buf[8 * 1024];
-
-	while ((nr = read(from, buf, sizeof(buf))) > 0)
-		for (off = 0; nr > 0; nr -= nw, off += nw)
-			if ((nw = write(to, buf + off, nr)) < 0)
-				pw_error(tmp_file, 1, 1);
-
-	if (nr < 0)
-		pw_error(orig_file, 1, 1);
-#ifdef HAVE_EXPLICIT_BZERO
-	explicit_bzero(buf, sizeof(buf));
-#endif
-}
-
 static void pw_init(void)
 {
 	struct rlimit rlim;
@@ -139,14 +122,19 @@ static FILE * pw_tmpfile(int lockfd)
 {
 	FILE *fd;
 	char *tmpname = NULL;
+	int res;
 
 	if ((fd = xfmkstemp(&tmpname, "/etc", ".vipw")) == NULL) {
 		ulckpwdf();
 		err(EXIT_FAILURE, _("can't open temporary file"));
 	}
 
-	copyfile(lockfd, fileno(fd));
 	tmp_file = tmpname;
+	res = ul_copy_file(lockfd, fileno(fd));
+	if (res == -1)
+		pw_error(orig_file, 1, 1);
+	else if (res == -2)
+		pw_error(tmp_file, 1, 1);
 	return fd;
 }