glib-2.0: fix CVE-2021-28153

Backport patches to fix CVE-2021-28153.

(From OE-Core rev: 8a0aae46bc87c00fb4d32f6ce5567cc44cae6d34)

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This commit is contained in:
Chen Qi
2021-04-25 16:44:00 +08:00
committed by Richard Purdie
parent aa8618b624
commit 80c76a82ec
6 changed files with 503 additions and 0 deletions

View File

@@ -0,0 +1,32 @@
From 48dd0d030a2b5240457472d40d8691b80bf5fa78 Mon Sep 17 00:00:00 2001
From: Philip Withnall <pwithnall@endlessos.org>
Date: Wed, 24 Feb 2021 17:33:38 +0000
Subject: [PATCH 1/5] glocalfileoutputstream: Fix a typo in a comment
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
CVE: CVE-2021-28153
Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/glib/-/issues/2325]
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
gio/glocalfileoutputstream.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gio/glocalfileoutputstream.c b/gio/glocalfileoutputstream.c
index f34c3e4..e3d31d6 100644
--- a/gio/glocalfileoutputstream.c
+++ b/gio/glocalfileoutputstream.c
@@ -854,7 +854,7 @@ handle_overwrite_open (const char *filename,
mode = mode_from_flags_or_info (flags, reference_info);
/* We only need read access to the original file if we are creating a backup.
- * We also add O_CREATE to avoid a race if the file was just removed */
+ * We also add O_CREAT to avoid a race if the file was just removed */
if (create_backup || readable)
open_flags = O_RDWR | O_CREAT | O_BINARY;
else
--
2.17.1

View File

@@ -0,0 +1,47 @@
From 3d7f54ae4cfdddaf1a807879d9263e16cd12ffd3 Mon Sep 17 00:00:00 2001
From: Philip Withnall <pwithnall@endlessos.org>
Date: Wed, 24 Feb 2021 17:34:32 +0000
Subject: [PATCH 2/5] tests: Stop using g_test_bug_base() in file tests
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Since a following commit is going to add a new test which references
Gitlab, so its best to move the URI bases inside the test cases.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
CVE: CVE-2021-28153
Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/glib/-/issues/2325]
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
gio/tests/file.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/gio/tests/file.c b/gio/tests/file.c
index d876965..39d51da 100644
--- a/gio/tests/file.c
+++ b/gio/tests/file.c
@@ -686,7 +686,7 @@ test_replace_cancel (void)
guint count;
GError *error = NULL;
- g_test_bug ("629301");
+ g_test_bug ("https://bugzilla.gnome.org/629301");
path = g_dir_make_tmp ("g_file_replace_cancel_XXXXXX", &error);
g_assert_no_error (error);
@@ -1785,8 +1785,6 @@ main (int argc, char *argv[])
{
g_test_init (&argc, &argv, NULL);
- g_test_bug_base ("http://bugzilla.gnome.org/");
-
g_test_add_func ("/file/basic", test_basic);
g_test_add_func ("/file/build-filename", test_build_filename);
g_test_add_func ("/file/parent", test_parent);
--
2.17.1

View File

@@ -0,0 +1,60 @@
From 8cc84a2f8c668541aaba584cb9b73c98afeb8e2d Mon Sep 17 00:00:00 2001
From: Philip Withnall <pwithnall@endlessos.org>
Date: Wed, 10 Mar 2021 16:05:55 +0000
Subject: [PATCH 3/5] glocalfileoutputstream: Factor out a flag check
This clarifies the code a little. It introduces no functional changes.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
CVE: CVE-2021-28153
Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/glib/-/issues/2325]
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
gio/glocalfileoutputstream.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/gio/glocalfileoutputstream.c b/gio/glocalfileoutputstream.c
index e3d31d6..392d0b0 100644
--- a/gio/glocalfileoutputstream.c
+++ b/gio/glocalfileoutputstream.c
@@ -850,6 +850,7 @@ handle_overwrite_open (const char *filename,
int res;
int mode;
int errsv;
+ gboolean replace_destination_set = (flags & G_FILE_CREATE_REPLACE_DESTINATION);
mode = mode_from_flags_or_info (flags, reference_info);
@@ -960,7 +961,7 @@ handle_overwrite_open (const char *filename,
* to a backup file and rewrite the contents of the file.
*/
- if ((flags & G_FILE_CREATE_REPLACE_DESTINATION) ||
+ if (replace_destination_set ||
(!(_g_stat_nlink (&original_stat) > 1) && !is_symlink))
{
char *dirname, *tmp_filename;
@@ -979,7 +980,7 @@ handle_overwrite_open (const char *filename,
/* try to keep permissions (unless replacing) */
- if ( ! (flags & G_FILE_CREATE_REPLACE_DESTINATION) &&
+ if (!replace_destination_set &&
(
#ifdef HAVE_FCHOWN
fchown (tmpfd, _g_stat_uid (&original_stat), _g_stat_gid (&original_stat)) == -1 ||
@@ -1120,7 +1121,7 @@ handle_overwrite_open (const char *filename,
}
}
- if (flags & G_FILE_CREATE_REPLACE_DESTINATION)
+ if (replace_destination_set)
{
g_close (fd, NULL);
--
2.17.1

View File

@@ -0,0 +1,294 @@
From ed8f2235da7d2a408bfa18c1003f4a07f90b05e8 Mon Sep 17 00:00:00 2001
From: Philip Withnall <pwithnall@endlessos.org>
Date: Wed, 24 Feb 2021 17:36:07 +0000
Subject: [PATCH 4/5] glocalfileoutputstream: Fix CREATE_REPLACE_DESTINATION
with symlinks
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The `G_FILE_CREATE_REPLACE_DESTINATION` flag is equivalent to unlinking
the destination file and re-creating it from scratch. That did
previously work, but in the process the code would call `open(O_CREAT)`
on the file. If the file was a dangling symlink, this would create the
destination file (empty). Thats not an intended side-effect, and has
security implications if the symlink is controlled by a lower-privileged
process.
Fix that by not opening the destination file if its a symlink, and
adjusting the rest of the code to cope with
- the fact that `fd == -1` is not an error iff `is_symlink` is true,
- and that `original_stat` will contain the `lstat()` results for the
symlink now, rather than the `stat()` results for its target (again,
iff `is_symlink` is true).
This means that the target of the dangling symlink is no longer created,
which was the bug. The symlink itself continues to be replaced (as
before) with the new file — this is the intended behaviour of
`g_file_replace()`.
The behaviour for non-symlink cases, or cases where the symlink was not
dangling, should be unchanged.
Includes a unit test.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Fixes: #2325
CVE: CVE-2021-28153
Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/glib/-/issues/2325]
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
gio/glocalfileoutputstream.c | 77 ++++++++++++++++++-------
gio/tests/file.c | 108 +++++++++++++++++++++++++++++++++++
2 files changed, 163 insertions(+), 22 deletions(-)
diff --git a/gio/glocalfileoutputstream.c b/gio/glocalfileoutputstream.c
index 392d0b0..a2c7e3c 100644
--- a/gio/glocalfileoutputstream.c
+++ b/gio/glocalfileoutputstream.c
@@ -878,16 +878,22 @@ handle_overwrite_open (const char *filename,
/* Could be a symlink, or it could be a regular ELOOP error,
* but then the next open will fail too. */
is_symlink = TRUE;
- fd = g_open (filename, open_flags, mode);
+ if (!replace_destination_set)
+ fd = g_open (filename, open_flags, mode);
}
-#else
- fd = g_open (filename, open_flags, mode);
- errsv = errno;
+#else /* if !O_NOFOLLOW */
/* This is racy, but we do it as soon as possible to minimize the race */
is_symlink = g_file_test (filename, G_FILE_TEST_IS_SYMLINK);
+
+ if (!is_symlink || !replace_destination_set)
+ {
+ fd = g_open (filename, open_flags, mode);
+ errsv = errno;
+ }
#endif
- if (fd == -1)
+ if (fd == -1 &&
+ (!is_symlink || !replace_destination_set))
{
char *display_name = g_filename_display_name (filename);
g_set_error (error, G_IO_ERROR,
@@ -898,15 +904,30 @@ handle_overwrite_open (const char *filename,
return -1;
}
- res = g_local_file_fstat (fd,
- G_LOCAL_FILE_STAT_FIELD_TYPE |
- G_LOCAL_FILE_STAT_FIELD_MODE |
- G_LOCAL_FILE_STAT_FIELD_UID |
- G_LOCAL_FILE_STAT_FIELD_GID |
- G_LOCAL_FILE_STAT_FIELD_MTIME |
- G_LOCAL_FILE_STAT_FIELD_NLINK,
- G_LOCAL_FILE_STAT_FIELD_ALL, &original_stat);
- errsv = errno;
+ if (!is_symlink)
+ {
+ res = g_local_file_fstat (fd,
+ G_LOCAL_FILE_STAT_FIELD_TYPE |
+ G_LOCAL_FILE_STAT_FIELD_MODE |
+ G_LOCAL_FILE_STAT_FIELD_UID |
+ G_LOCAL_FILE_STAT_FIELD_GID |
+ G_LOCAL_FILE_STAT_FIELD_MTIME |
+ G_LOCAL_FILE_STAT_FIELD_NLINK,
+ G_LOCAL_FILE_STAT_FIELD_ALL, &original_stat);
+ errsv = errno;
+ }
+ else
+ {
+ res = g_local_file_lstat (filename,
+ G_LOCAL_FILE_STAT_FIELD_TYPE |
+ G_LOCAL_FILE_STAT_FIELD_MODE |
+ G_LOCAL_FILE_STAT_FIELD_UID |
+ G_LOCAL_FILE_STAT_FIELD_GID |
+ G_LOCAL_FILE_STAT_FIELD_MTIME |
+ G_LOCAL_FILE_STAT_FIELD_NLINK,
+ G_LOCAL_FILE_STAT_FIELD_ALL, &original_stat);
+ errsv = errno;
+ }
if (res != 0)
{
@@ -923,16 +944,27 @@ handle_overwrite_open (const char *filename,
if (!S_ISREG (_g_stat_mode (&original_stat)))
{
if (S_ISDIR (_g_stat_mode (&original_stat)))
- g_set_error_literal (error,
- G_IO_ERROR,
- G_IO_ERROR_IS_DIRECTORY,
- _("Target file is a directory"));
- else
- g_set_error_literal (error,
+ {
+ g_set_error_literal (error,
+ G_IO_ERROR,
+ G_IO_ERROR_IS_DIRECTORY,
+ _("Target file is a directory"));
+ goto err_out;
+ }
+ else if (!is_symlink ||
+#ifdef S_ISLNK
+ !S_ISLNK (_g_stat_mode (&original_stat))
+#else
+ FALSE
+#endif
+ )
+ {
+ g_set_error_literal (error,
G_IO_ERROR,
G_IO_ERROR_NOT_REGULAR_FILE,
_("Target file is not a regular file"));
- goto err_out;
+ goto err_out;
+ }
}
if (etag != NULL)
@@ -1015,7 +1047,8 @@ handle_overwrite_open (const char *filename,
}
}
- g_close (fd, NULL);
+ if (fd >= 0)
+ g_close (fd, NULL);
*temp_filename = tmp_filename;
return tmpfd;
}
diff --git a/gio/tests/file.c b/gio/tests/file.c
index 39d51da..ddd1ffc 100644
--- a/gio/tests/file.c
+++ b/gio/tests/file.c
@@ -805,6 +805,113 @@ test_replace_cancel (void)
g_object_unref (tmpdir);
}
+static void
+test_replace_symlink (void)
+{
+#ifdef G_OS_UNIX
+ gchar *tmpdir_path = NULL;
+ GFile *tmpdir = NULL, *source_file = NULL, *target_file = NULL;
+ GFileOutputStream *stream = NULL;
+ const gchar *new_contents = "this is a test message which should be written to source and not target";
+ gsize n_written;
+ GFileEnumerator *enumerator = NULL;
+ GFileInfo *info = NULL;
+ gchar *contents = NULL;
+ gsize length = 0;
+ GError *local_error = NULL;
+
+ g_test_bug ("https://gitlab.gnome.org/GNOME/glib/-/issues/2325");
+ g_test_summary ("Test that G_FILE_CREATE_REPLACE_DESTINATION doesnt follow symlinks");
+
+ /* Create a fresh, empty working directory. */
+ tmpdir_path = g_dir_make_tmp ("g_file_replace_symlink_XXXXXX", &local_error);
+ g_assert_no_error (local_error);
+ tmpdir = g_file_new_for_path (tmpdir_path);
+
+ g_test_message ("Using temporary directory %s", tmpdir_path);
+ g_free (tmpdir_path);
+
+ /* Create symlink `source` which points to `target`. */
+ source_file = g_file_get_child (tmpdir, "source");
+ target_file = g_file_get_child (tmpdir, "target");
+ g_file_make_symbolic_link (source_file, "target", NULL, &local_error);
+ g_assert_no_error (local_error);
+
+ /* Ensure that `target` doesnt exist */
+ g_assert_false (g_file_query_exists (target_file, NULL));
+
+ /* Replace the `source` symlink with a regular file using
+ * %G_FILE_CREATE_REPLACE_DESTINATION, which should replace it *without*
+ * following the symlink */
+ stream = g_file_replace (source_file, NULL, FALSE /* no backup */,
+ G_FILE_CREATE_REPLACE_DESTINATION, NULL, &local_error);
+ g_assert_no_error (local_error);
+
+ g_output_stream_write_all (G_OUTPUT_STREAM (stream), new_contents, strlen (new_contents),
+ &n_written, NULL, &local_error);
+ g_assert_no_error (local_error);
+ g_assert_cmpint (n_written, ==, strlen (new_contents));
+
+ g_output_stream_close (G_OUTPUT_STREAM (stream), NULL, &local_error);
+ g_assert_no_error (local_error);
+
+ g_clear_object (&stream);
+
+ /* At this point, there should still only be one file: `source`. It should
+ * now be a regular file. `target` should not exist. */
+ enumerator = g_file_enumerate_children (tmpdir,
+ G_FILE_ATTRIBUTE_STANDARD_NAME ","
+ G_FILE_ATTRIBUTE_STANDARD_TYPE,
+ G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS, NULL, &local_error);
+ g_assert_no_error (local_error);
+
+ info = g_file_enumerator_next_file (enumerator, NULL, &local_error);
+ g_assert_no_error (local_error);
+ g_assert_nonnull (info);
+
+ g_assert_cmpstr (g_file_info_get_name (info), ==, "source");
+ g_assert_cmpint (g_file_info_get_file_type (info), ==, G_FILE_TYPE_REGULAR);
+
+ g_clear_object (&info);
+
+ info = g_file_enumerator_next_file (enumerator, NULL, &local_error);
+ g_assert_no_error (local_error);
+ g_assert_null (info);
+
+ g_file_enumerator_close (enumerator, NULL, &local_error);
+ g_assert_no_error (local_error);
+ g_clear_object (&enumerator);
+
+ /* Double-check that `target` doesnt exist */
+ g_assert_false (g_file_query_exists (target_file, NULL));
+
+ /* Check the content of `source`. */
+ g_file_load_contents (source_file,
+ NULL,
+ &contents,
+ &length,
+ NULL,
+ &local_error);
+ g_assert_no_error (local_error);
+ g_assert_cmpstr (contents, ==, new_contents);
+ g_assert_cmpuint (length, ==, strlen (new_contents));
+ g_free (contents);
+
+ /* Tidy up. */
+ g_file_delete (source_file, NULL, &local_error);
+ g_assert_no_error (local_error);
+
+ g_file_delete (tmpdir, NULL, &local_error);
+ g_assert_no_error (local_error);
+
+ g_clear_object (&target_file);
+ g_clear_object (&source_file);
+ g_clear_object (&tmpdir);
+#else /* if !G_OS_UNIX */
+ g_test_skip ("Symlink replacement tests can only be run on Unix")
+#endif
+}
+
static void
on_file_deleted (GObject *object,
GAsyncResult *result,
@@ -1798,6 +1905,7 @@ main (int argc, char *argv[])
g_test_add_data_func ("/file/async-create-delete/4096", GINT_TO_POINTER (4096), test_create_delete);
g_test_add_func ("/file/replace-load", test_replace_load);
g_test_add_func ("/file/replace-cancel", test_replace_cancel);
+ g_test_add_func ("/file/replace-symlink", test_replace_symlink);
g_test_add_func ("/file/async-delete", test_async_delete);
g_test_add_func ("/file/copy-preserve-mode", test_copy_preserve_mode);
g_test_add_func ("/file/measure", test_measure);
--
2.17.1

View File

@@ -0,0 +1,60 @@
From ab4ee65fb5778964fa3cca9b3d6749711ef9ba19 Mon Sep 17 00:00:00 2001
From: Philip Withnall <pwithnall@endlessos.org>
Date: Wed, 24 Feb 2021 17:42:24 +0000
Subject: [PATCH 5/5] glocalfileoutputstream: Add a missing O_CLOEXEC flag to
replace()
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
CVE: CVE-2021-28153
Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/glib/-/issues/2325]
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
gio/glocalfileoutputstream.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/gio/glocalfileoutputstream.c b/gio/glocalfileoutputstream.c
index a2c7e3c..4c512ea 100644
--- a/gio/glocalfileoutputstream.c
+++ b/gio/glocalfileoutputstream.c
@@ -63,6 +63,12 @@
#define O_BINARY 0
#endif
+#ifndef O_CLOEXEC
+#define O_CLOEXEC 0
+#else
+#define HAVE_O_CLOEXEC 1
+#endif
+
struct _GLocalFileOutputStreamPrivate {
char *tmp_filename;
char *original_filename;
@@ -1239,7 +1245,7 @@ _g_local_file_output_stream_replace (const char *filename,
sync_on_close = FALSE;
/* If the file doesn't exist, create it */
- open_flags = O_CREAT | O_EXCL | O_BINARY;
+ open_flags = O_CREAT | O_EXCL | O_BINARY | O_CLOEXEC;
if (readable)
open_flags |= O_RDWR;
else
@@ -1269,8 +1275,11 @@ _g_local_file_output_stream_replace (const char *filename,
set_error_from_open_errno (filename, error);
return NULL;
}
-
-
+#if !defined(HAVE_O_CLOEXEC) && defined(F_SETFD)
+ else
+ fcntl (fd, F_SETFD, FD_CLOEXEC);
+#endif
+
stream = g_object_new (G_TYPE_LOCAL_FILE_OUTPUT_STREAM, NULL);
stream->priv->fd = fd;
stream->priv->sync_on_close = sync_on_close;
--
2.17.1

View File

@@ -50,6 +50,16 @@ SRC_URI += "\
file://0028-gresource-Fix-a-pointer-mismatch-with-an-atomic-load.patch \
file://0029-docs-Document-not-to-use-volatile-qualifiers.patch \
"
# Fix CVE-2021-28153
SRC_URI += "\
file://0001-glocalfileoutputstream-Fix-a-typo-in-a-comment.patch \
file://0002-tests-Stop-using-g_test_bug_base-in-file-tests.patch \
file://0003-glocalfileoutputstream-Factor-out-a-flag-check.patch \
file://0004-glocalfileoutputstream-Fix-CREATE_REPLACE_DESTINATIO.patch \
file://0005-glocalfileoutputstream-Add-a-missing-O_CLOEXEC-flag-.patch \
"
SRC_URI_append_class-native = " file://relocate-modules.patch"
SRC_URI[sha256sum] = "09f158769f6f26b31074e15b1ac80ec39b13b53102dfae66cfe826fb2cc65502"