Ensure that getpwent() is used in setpwent(), getpwent(),

endpwend() sequences (ditto for getgrent(), getspent(), and
getsgent()). The only real (minor) issue was in login, which kept
the passwd file open.
* libmisc/entry.c: Remove unneeded setspent() and endspent() (only
  getspnam is called in the middle).
* libmisc/find_new_ids.c: Make sure to close the password and
  group files with endpwent() and endgrent().
* libmisc/pwdcheck.c: Remove unneeded endspent() (only getspnam()
  is called before).
* src/lastlog.c, src/passwd.c, src/groupmod.c, src/faillog.c,
  src/groups.c: Make sure to close
  the password file with endpwent().
* src/login.c: Remove unneeded setpwent() (only xgetpwnam is
  called before).
* src/login.c, src/newgrp.c: Fix typos in comments.

libmisc/entry.c

@@ -54,14 +54,11 @@ void pw_entry (const char *name, struct passwd *pwent)
 		pwent->pw_dir = xstrdup (passwd->pw_dir);
 		pwent->pw_shell = xstrdup (passwd->pw_shell);
 #if !defined(AUTOSHADOW)
-		setspent ();
 		/* local, no need for xgetspnam */
 		if ((spwd = getspnam (name))) {
 			pwent->pw_passwd = xstrdup (spwd->sp_pwdp);
-			endspent ();
 			return;
 		}
-		endspent ();
 #endif
 		pwent->pw_passwd = xstrdup (passwd->pw_passwd);
 	}

libmisc/find_new_ids.c

@@ -65,6 +65,7 @@ int find_new_uid (int sys_user, uid_t *uid, uid_t const *preferred_uid)
 			user_id = pwd->pw_uid + 1;
 		}
 	}
+	endpwent ();
 
 	/*
 	 * If a user with UID equal to UID_MAX exists, the above algorithm
@@ -146,6 +147,7 @@ int find_new_gid (int sys_group, gid_t *gid, gid_t const *preferred_gid)
 			group_id = grp->gr_gid + 1;
 		}
 	}
+	endgrent ();
 
 	/*
 	 * If a group with GID equal to GID_MAX exists, the above algorithm

libmisc/pwdcheck.c

@@ -46,7 +46,6 @@ void passwd_check (const char *user, const char *passwd, const char *progname)
 
 	if ((sp = getspnam (user))) /* !USE_PAM, no need for xgetspnam */
 		passwd = sp->sp_pwdp;
-	endspent ();
 	if (pw_auth (passwd, user, PW_LOGIN, (char *) 0) != 0) {
 		SYSLOG ((LOG_WARN, WRONGPWD2, user));
 		sleep (1);