Re: localcharset: fix security problem

[Bruno Haible]

Hi,

I wrote on 2009-10-18:
>       * m4/fcntl_h.m4 (gl_FCNTL_O_FLAGS): New macro, extracted from
>       gl_FCNTL_H.
>       (gl_FCNTL_H): Require it.
>       * modules/localcharset (Files): Add m4/fcntl_h.m4.

When the 'localcharset' module contains a .m4 file, GNU gettextize will
distribute this .m4 file. But with the frequent changes that we are
doing to fcntl_h.m4, there are likely to be incompatibilities in the
future. In fact, some change that occurred between October and now caused
a build failure in GNU gettext.

So it's better to let 'gettextize' only distribute the macro that it really
needs. This is done by splitting the fcntl_h.m4 file:


2009-12-25  Bruno Haible  <address@hidden>

        Move gl_FCNTL_O_FLAGS to a separate .m4 file.
        * m4/fcntl-o.m4: New file, extracted from m4/fcntl_h.m4.
        * m4/fcntl_h.m4 (gl_FCNTL_O_FLAGS): Remove macro.
        * modules/fcntl-h (Files): Add m4/fcntl-o.m4.
        * modules/localcharset (Files): Likewise. Remove m4/fcntl_h.m4.

Changing permissions from . to 100644
--- m4/fcntl-o.m4.orig  Tue Apr 14 12:31:40 2009
+++ m4/fcntl-o.m4       Fri Dec 25 13:04:33 2009
@@ -0,0 +1,81 @@
+# fcntl-o.m4 serial 1
+dnl Copyright (C) 2006, 2009 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Written by Paul Eggert.
+
+# Test whether the flags O_NOATIME and O_NOFOLLOW actually work.
+# Define HAVE_WORKING_O_NOATIME to 1 if O_NOATIME works, or to 0 otherwise.
+# Define HAVE_WORKING_O_NOFOLLOW to 1 if O_NOFOLLOW works, or to 0 otherwise.
+AC_DEFUN([gl_FCNTL_O_FLAGS],
+[
+  dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW.
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+  AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
+    [AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#include <sys/types.h>
+           #include <sys/stat.h>
+           #include <unistd.h>
+           #include <fcntl.h>
+           #ifndef O_NOATIME
+            #define O_NOATIME 0
+           #endif
+           #ifndef O_NOFOLLOW
+            #define O_NOFOLLOW 0
+           #endif
+           static int const constants[] =
+            {
+              O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
+              O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
+            };
+          ]],
+          [[
+            int status = !constants;
+            {
+              static char const sym[] = "conftest.sym";
+              if (symlink (".", sym) != 0
+                  || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0)
+                status |= 32;
+              unlink (sym);
+            }
+            {
+              static char const file[] = "confdefs.h";
+              int fd = open (file, O_RDONLY | O_NOATIME);
+              char c;
+              struct stat st0, st1;
+              if (fd < 0
+                  || fstat (fd, &st0) != 0
+                  || sleep (1) != 0
+                  || read (fd, &c, 1) != 1
+                  || close (fd) != 0
+                  || stat (file, &st1) != 0
+                  || st0.st_atime != st1.st_atime)
+                status |= 64;
+            }
+            return status;]])],
+       [gl_cv_header_working_fcntl_h=yes],
+       [case $? in #(
+        32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
+        64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
+        96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
+         *) gl_cv_header_working_fcntl_h='no';;
+        esac],
+       [gl_cv_header_working_fcntl_h=cross-compiling])])
+
+  case $gl_cv_header_working_fcntl_h in #(
+  *O_NOATIME* | no | cross-compiling) ac_val=0;; #(
+  *) ac_val=1;;
+  esac
+  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOATIME], [$ac_val],
+    [Define to 1 if O_NOATIME works.])
+
+  case $gl_cv_header_working_fcntl_h in #(
+  *O_NOFOLLOW* | no | cross-compiling) ac_val=0;; #(
+  *) ac_val=1;;
+  esac
+  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
+    [Define to 1 if O_NOFOLLOW works.])
+])
--- m4/fcntl_h.m4.orig  Fri Dec 25 13:05:39 2009
+++ m4/fcntl_h.m4       Fri Dec 25 13:04:33 2009
@@ -1,4 +1,4 @@
-# serial 8
+# serial 9
 # Configure fcntl.h.
 dnl Copyright (C) 2006, 2007, 2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
@@ -14,80 +14,6 @@
   gl_CHECK_NEXT_HEADERS([fcntl.h])
 ])
 
-# Test whether the flags O_NOATIME and O_NOFOLLOW actually work.
-# Define HAVE_WORKING_O_NOATIME to 1 if O_NOATIME works, or to 0 otherwise.
-# Define HAVE_WORKING_O_NOFOLLOW to 1 if O_NOFOLLOW works, or to 0 otherwise.
-AC_DEFUN([gl_FCNTL_O_FLAGS],
-[
-  dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW.
-  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
-  AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
-    [AC_RUN_IFELSE(
-       [AC_LANG_PROGRAM(
-          [[#include <sys/types.h>
-           #include <sys/stat.h>
-           #include <unistd.h>
-           #include <fcntl.h>
-           #ifndef O_NOATIME
-            #define O_NOATIME 0
-           #endif
-           #ifndef O_NOFOLLOW
-            #define O_NOFOLLOW 0
-           #endif
-           static int const constants[] =
-            {
-              O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
-              O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
-            };
-          ]],
-          [[
-            int status = !constants;
-            {
-              static char const sym[] = "conftest.sym";
-              if (symlink (".", sym) != 0
-                  || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0)
-                status |= 32;
-              unlink (sym);
-            }
-            {
-              static char const file[] = "confdefs.h";
-              int fd = open (file, O_RDONLY | O_NOATIME);
-              char c;
-              struct stat st0, st1;
-              if (fd < 0
-                  || fstat (fd, &st0) != 0
-                  || sleep (1) != 0
-                  || read (fd, &c, 1) != 1
-                  || close (fd) != 0
-                  || stat (file, &st1) != 0
-                  || st0.st_atime != st1.st_atime)
-                status |= 64;
-            }
-            return status;]])],
-       [gl_cv_header_working_fcntl_h=yes],
-       [case $? in #(
-        32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
-        64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
-        96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
-         *) gl_cv_header_working_fcntl_h='no';;
-        esac],
-       [gl_cv_header_working_fcntl_h=cross-compiling])])
-
-  case $gl_cv_header_working_fcntl_h in #(
-  *O_NOATIME* | no | cross-compiling) ac_val=0;; #(
-  *) ac_val=1;;
-  esac
-  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOATIME], [$ac_val],
-    [Define to 1 if O_NOATIME works.])
-
-  case $gl_cv_header_working_fcntl_h in #(
-  *O_NOFOLLOW* | no | cross-compiling) ac_val=0;; #(
-  *) ac_val=1;;
-  esac
-  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
-    [Define to 1 if O_NOFOLLOW works.])
-])
-
 AC_DEFUN([gl_FCNTL_MODULE_INDICATOR],
 [
   dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
--- modules/fcntl-h.orig        Fri Dec 25 13:05:39 2009
+++ modules/fcntl-h     Fri Dec 25 13:04:33 2009
@@ -4,6 +4,7 @@
 Files:
 lib/fcntl.in.h
 m4/fcntl_h.m4
+m4/fcntl-o.m4
 
 Depends-on:
 include_next
--- modules/localcharset.orig   Fri Dec 25 13:05:39 2009
+++ modules/localcharset        Fri Dec 25 13:04:32 2009
@@ -14,7 +14,7 @@
 lib/ref-add.sin
 lib/ref-del.sin
 m4/codeset.m4
-m4/fcntl_h.m4
+m4/fcntl-o.m4
 m4/glibc21.m4
 m4/localcharset.m4