Use setpwent()/endpwent() + all the shadow variants to make sure

we don't inadvertantly leak an fd to the child.  Apparently Linux's
shadow routines leave the fd open even if you don't call setspent().
Reported by mike@gistnet.com; different patch used.

diff --git a/getspwuid.c b/getspwuid.c
index 07286d20c1dfc942eab9cc1fa67cab24b1cd4c65..0e4fa059d396089af4ef16304597c87d5ec57680 100644 (file)
--- a/getspwuid.c
+++ b/getspwuid.c
@@ -114,72 +114,93 @@ sudo_getshell(pw)
 }
 
 /*
- * Return the encrypted password for the user described by pw.  If shadow
- * passwords are in use, look in the shadow file.
+ * Return a copy of the encrypted password for the user described by pw.
+ * If shadow passwords are in use, look in the shadow file.
  */
 char *
 sudo_getepw(pw)
     struct passwd *pw;
 {
+    char *epw;
 
     /* If there is a function to check for shadow enabled, use it... */
 #ifdef HAVE_ISCOMSEC
     if (!iscomsec())
-       return(pw->pw_passwd);
+       return(estrdup(pw->pw_passwd));
 #endif /* HAVE_ISCOMSEC */
 #ifdef HAVE_ISSECURE
     if (!issecure())
-       return(pw->pw_passwd);
+       return(estrdup(pw->pw_passwd));
 #endif /* HAVE_ISSECURE */
 
+    epw = NULL;
 #ifdef HAVE_GETPRPWNAM
     {
        struct pr_passwd *spw;
 
-       spw = getprpwnam(pw->pw_name);
-       if (spw != NULL && spw->ufld.fd_encrypt != NULL) {
+       setprpwent();
+       if ((spw = getprpwnam(pw->pw_name)) && spw->ufld.fd_encrypt) {
 # ifdef __alpha
            crypt_type = spw->ufld.fd_oldcrypt;
 # endif /* __alpha */
-           return(spw->ufld.fd_encrypt);
+           epw = estrdup(spw->ufld.fd_encrypt);
        }
+       endprpwent();
+       if (epw)
+           return(epw);
     }
 #endif /* HAVE_GETPRPWNAM */
 #ifdef HAVE_GETSPNAM
     {
        struct spwd *spw;
 
+       setspent();
        if ((spw = getspnam(pw->pw_name)) && spw->sp_pwdp)
-           return(spw->sp_pwdp);
+           epw = estrdup(spw->sp_pwdp);
+       endspent();
+       if (epw)
+           return(epw);
     }
 #endif /* HAVE_GETSPNAM */
 #ifdef HAVE_GETSPWUID
     {
        struct s_passwd *spw;
 
+       setspwent();
        if ((spw = getspwuid(pw->pw_uid)) && spw->pw_passwd)
-           return(spw->pw_passwd);
+           epw = estrdup(spw->pw_passwd);
+       endspwent();
+       if (epw)
+           return(epw);
     }
 #endif /* HAVE_GETSPWUID */
 #ifdef HAVE_GETPWANAM
     {
        struct passwd_adjunct *spw;
 
+       setpwaent();
        if ((spw = getpwanam(pw->pw_name)) && spw->pwa_passwd)
-           return(spw->pwa_passwd);
+           epw = estrdup(spw->pwa_passwd);
+       endpwaent();
+       if (epw)
+           return(epw);
     }
 #endif /* HAVE_GETPWANAM */
 #ifdef HAVE_GETAUTHUID
     {
        AUTHORIZATION *spw;
 
+       setauthent();
        if ((spw = getauthuid(pw->pw_uid)) && spw->a_password)
-           return(spw->a_password);
+           epw = estrdup(spw->a_password);
+       endauthent();
+       if (epw)
+           return(epw);
     }
 #endif /* HAVE_GETAUTHUID */
 
     /* Fall back on normal password. */
-    return(pw->pw_passwd);
+    return(estrdup(pw->pw_passwd));
 }
 
 /*
@@ -210,7 +231,7 @@ sudo_pwdup(pw)
     local_pw->pw_shell = estrdup(sudo_getshell(pw));
 
     /* pw_passwd gets a shadow password if applicable */
-    local_pw->pw_passwd = estrdup(sudo_getepw(pw));
+    local_pw->pw_passwd = sudo_getepw(pw);
 
     return(local_pw);
 }

diff --git a/logging.c b/logging.c
index 767219671766b51bd638585a455aa34190cdcdbf..dc7f215924c6ffa9e250eb2b7b28194d5420eb5e 100644 (file)
--- a/logging.c
+++ b/logging.c
@@ -490,6 +490,9 @@ send_mail(line)
                }
                argv[i] = NULL;
 
+               /* Close password file so we don't leak the fd. */
+               endpwent();
+
                /* Run mailer as root so user cannot kill it. */
                set_perms(PERM_ROOT, 0);
                execv(mpath, argv);

diff --git a/sudo.c b/sudo.c
index b6c5fdf46d84b4a52c006398b6bd2781aa84aace..d57bf0445d2ff46aa6a1c515d41ffedd89e99da2 100644 (file)
--- a/sudo.c
+++ b/sudo.c
@@ -191,6 +191,7 @@ main(argc, argv, envp)
      * Setup signal handlers, turn off core dumps, and close open files.
      */
     initial_setup();
+    setpwent();
 
     /* Parse our arguments. */
     sudo_mode = parse_args();
@@ -338,6 +339,9 @@ main(argc, argv, envp)
                "please report this error at http://courtesan.com/sudo/bugs/");
        }
 
+       /* Close the password file */
+       endpwent();
+
        /* Reset signal mask before we exec. */
 #ifdef POSIX_SIGNALS
        (void) sigprocmask(SIG_SETMASK, &oset, NULL);