* locale/loadarchive.c (_nl_load_locale_from_archive): Check max file

	position indicated by locrectab against file bounds before rounding to
	page size.  In mapping loop, always set TO before breaking out of
	contiguous range coalescing loop.

	* locale/loadarchive.c (_nl_load_locale_from_archive): Use MAP_PRIVATE
	(or MAP_COPY if available) instead of MAP_SHARED.

diff --git a/ChangeLog b/ChangeLog
index ac29548eac9ed9bbe51a4aa1047dfe5dd772644c..38cf4938b32833048969ca70d65f10150aaae83b 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2002-08-22  Roland McGrath  <roland@redhat.com>
 
+       * locale/loadarchive.c (_nl_load_locale_from_archive): Check max file
+       position indicated by locrectab against file bounds before rounding to
+       page size.  In mapping loop, always set TO before breaking out of
+       contiguous range coalescing loop.
+
+       * locale/loadarchive.c (_nl_load_locale_from_archive): Use MAP_PRIVATE
+       (or MAP_COPY if available) instead of MAP_SHARED.
+
        * scripts/firstversions.awk: When encountering a version newer than
        the specified earliest version, be sure to emit the specified earliest
        version first if any renaming of an older version to that has been.

diff --git a/locale/loadarchive.c b/locale/loadarchive.c
index e32e8c76481a94d26eb0446e875258f6e346df57..d25334a7fd97f37c53d54b96cc83dd42e48caa2b 100644 (file)
--- a/locale/loadarchive.c
+++ b/locale/loadarchive.c
@@ -45,6 +45,19 @@ static const char archfname[] = LOCALEDIR "/locale-archive";
    cover the header plus the initial locale.  */
 #define ARCHIVE_MAPPING_WINDOW (2 * 1024 * 1024)
 
+#ifndef MAP_COPY
+/* This is not quite as good as MAP_COPY since unexamined pages
+   can change out from under us and give us inconsistent data.
+   But we rely on the user not to diddle the system's live archive.
+   Even though we only ever use PROT_READ, using MAP_SHARED would
+   not give the system sufficient freedom to e.g. let the on disk
+   file go away because it doesn't know we won't call mprotect later.  */
+# define MAP_COPY MAP_PRIVATE
+#endif
+#ifndef MAP_FILE
+ /* Some systems do not have this flag; it is superfluous.  */
+# define MAP_FILE 0
+#endif
 
 /* Record of contiguous pages already mapped from the locale archive.  */
 struct archmapped
@@ -208,7 +221,7 @@ _nl_load_locale_from_archive (int category, const char **namep)
       mapsize = (sizeof (void *) > 4 ? archive_stat.st_size
                 : MIN (archive_stat.st_size, ARCHIVE_MAPPING_WINDOW));
 
-      result = __mmap64 (NULL, mapsize, PROT_READ, MAP_SHARED, fd, 0);
+      result = __mmap64 (NULL, mapsize, PROT_READ, MAP_FILE|MAP_COPY, fd, 0);
       if (result == MAP_FAILED)
        goto close_and_out;
 
@@ -226,7 +239,8 @@ _nl_load_locale_from_archive (int category, const char **namep)
          /* Freakishly long header.  */
          /* XXX could use mremap when available */
          mapsize = (headsize + ps - 1) & ~(ps - 1);
-         result = __mmap64 (NULL, mapsize, PROT_READ, MAP_SHARED, fd, 0);
+         result = __mmap64 (NULL, mapsize, PROT_READ, MAP_FILE|MAP_COPY,
+                            fd, 0);
          if (result == MAP_FAILED)
            goto close_and_out;
        }
@@ -357,20 +371,21 @@ _nl_load_locale_from_archive (int category, const char **namep)
          upper = cnt;
          do
            {
+             to = ranges[upper].from + ranges[upper].len;
+             if (to > archive_stat.st_size)
+               /* The archive locrectab contains bogus offsets.  */
+               return NULL;
+             to = (to + ps - 1) & ~(ps - 1);
+
              /* If a range is already mmaped in, stop.  */
              if (mapped != NULL && ranges[upper].from >= mapped->from)
                break;
-             to = ((ranges[upper].from + ranges[upper].len + ps - 1)
-                   & ~(ps - 1));
+
              ++upper;
            }
          /* Loop while still in contiguous pages. */
          while (upper < nranges && ranges[upper].from < to + ps);
 
-         if (to > archive_stat.st_size)
-           /* The archive locrectab contains bogus offsets.  */
-           return NULL;
-
          /* Open the file if it hasn't happened yet.  */
          if (fd == -1)
            {
@@ -391,7 +406,8 @@ _nl_load_locale_from_archive (int category, const char **namep)
            }
 
          /* Map the range from the archive.  */
-         addr = __mmap64 (NULL, to - from, PROT_READ, MAP_SHARED, fd, from);
+         addr = __mmap64 (NULL, to - from, PROT_READ, MAP_FILE|MAP_COPY,
+                          fd, from);
          if (addr == MAP_FAILED)
            return NULL;