[glib/glib-2-36] Ensure g_file_copy() does not temporarily expose private files
- From: Matthias Clasen <matthiasc src gnome org>
- To: commits-list gnome org
- Cc:
- Subject: [glib/glib-2-36] Ensure g_file_copy() does not temporarily expose private files
- Date: Sun, 9 Jun 2013 22:41:19 +0000 (UTC)
commit ffddb55ab3ef781822adfad1f64b32a2f1ef09a9
Author: Colin Walters <walters verbum org>
Date: Sun May 12 07:28:01 2013 +0100
Ensure g_file_copy() does not temporarily expose private files
Previously, g_file_copy() would (on Unix) create files with the
default mode of 644. For applications which might at user request
copy arbitrary private files such as ~/.ssh or /etc/shadow, a
world-readable copy would be temporarily exposed.
This patch is suboptimal in that it *only* fixes g_file_copy()
for the case where both source and destination are instances of
GLocalFile on Unix.
The reason for this is that the public GFile APIs for creating files
allow very limited control over the access permissions for the created
file; one can either say a file is "private" or not. Fixing
this by adding e.g. g_file_create_with_attributes() would make sense,
except this would entail 8 new API calls for all the variants of
_create(), _create_async(), _replace(), _replace_async(),
_create_readwrite(), _create_readwrite_async(), _replace_readwrite(),
_replace_readwrite_async(). That can be done as a separate patch
later.
https://bugzilla.gnome.org/show_bug.cgi?id=699959
gio/gfile.c | 24 +++++++++++++++++++++++-
gio/glocalfile.c | 23 ++++++++++++++---------
gio/glocalfile.h | 2 ++
gio/glocalfileoutputstream.c | 36 ++++++++++++++++++++++--------------
gio/glocalfileoutputstream.h | 2 ++
5 files changed, 63 insertions(+), 24 deletions(-)
---
diff --git a/gio/gfile.c b/gio/gfile.c
index 69b1bb7..88ecb34 100644
--- a/gio/gfile.c
+++ b/gio/gfile.c
@@ -60,6 +60,7 @@
#include "gfileoutputstream.h"
#include "glocalfileoutputstream.h"
#include "glocalfileiostream.h"
+#include "glocalfile.h"
#include "gcancellable.h"
#include "gasyncresult.h"
#include "gioerror.h"
@@ -3079,7 +3080,28 @@ file_copy_fallback (GFile *source,
do_set_attributes = TRUE;
}
- if (flags & G_FILE_COPY_OVERWRITE)
+ /* In the local file path, we pass down the source info which
+ * includes things like unix::mode, to ensure that the target file
+ * is not created with different permissions from the source file.
+ *
+ * If a future API like g_file_replace_with_info() is added, switch
+ * this code to use that.
+ */
+ if (G_IS_LOCAL_FILE (destination))
+ {
+ if (flags & G_FILE_COPY_OVERWRITE)
+ out = (GOutputStream*)_g_local_file_output_stream_replace (_g_local_file_get_filename (G_LOCAL_FILE
(destination)),
+ FALSE, NULL,
+ flags & G_FILE_COPY_BACKUP,
+ G_FILE_CREATE_REPLACE_DESTINATION,
+ info,
+ cancellable, error);
+ else
+ out = (GOutputStream*)_g_local_file_output_stream_create (_g_local_file_get_filename (G_LOCAL_FILE
(destination)),
+ FALSE, 0, info,
+ cancellable, error);
+ }
+ else if (flags & G_FILE_COPY_OVERWRITE)
{
out = (GOutputStream *)g_file_replace (destination,
NULL,
diff --git a/gio/glocalfile.c b/gio/glocalfile.c
index 9007faa..a4196dc 100644
--- a/gio/glocalfile.c
+++ b/gio/glocalfile.c
@@ -187,6 +187,11 @@ g_local_file_init (GLocalFile *local)
{
}
+const char *
+_g_local_file_get_filename (GLocalFile *file)
+{
+ return file->filename;
+}
static char *
canonicalize_filename (const char *filename)
@@ -1396,8 +1401,8 @@ g_local_file_create (GFile *file,
GError **error)
{
return _g_local_file_output_stream_create (G_LOCAL_FILE (file)->filename,
- FALSE,
- flags, cancellable, error);
+ FALSE, flags, NULL,
+ cancellable, error);
}
static GFileOutputStream *
@@ -1409,9 +1414,9 @@ g_local_file_replace (GFile *file,
GError **error)
{
return _g_local_file_output_stream_replace (G_LOCAL_FILE (file)->filename,
- FALSE,
- etag, make_backup, flags,
- cancellable, error);
+ FALSE,
+ etag, make_backup, flags, NULL,
+ cancellable, error);
}
static GFileIOStream *
@@ -1443,7 +1448,7 @@ g_local_file_create_readwrite (GFile *file,
GFileIOStream *res;
output = _g_local_file_output_stream_create (G_LOCAL_FILE (file)->filename,
- TRUE, flags,
+ TRUE, flags, NULL,
cancellable, error);
if (output == NULL)
return NULL;
@@ -1465,9 +1470,9 @@ g_local_file_replace_readwrite (GFile *file,
GFileIOStream *res;
output = _g_local_file_output_stream_replace (G_LOCAL_FILE (file)->filename,
- TRUE,
- etag, make_backup, flags,
- cancellable, error);
+ TRUE,
+ etag, make_backup, flags, NULL,
+ cancellable, error);
if (output == NULL)
return NULL;
diff --git a/gio/glocalfile.h b/gio/glocalfile.h
index abb36fa..4d02084 100644
--- a/gio/glocalfile.h
+++ b/gio/glocalfile.h
@@ -46,6 +46,8 @@ GType _g_local_file_get_type (void) G_GNUC_CONST;
GFile * _g_local_file_new (const char *filename);
+const char * _g_local_file_get_filename (GLocalFile *file);
+
G_END_DECLS
#endif /* __G_LOCAL_FILE_H__ */
diff --git a/gio/glocalfileoutputstream.c b/gio/glocalfileoutputstream.c
index 22fefc4..e971167 100644
--- a/gio/glocalfileoutputstream.c
+++ b/gio/glocalfileoutputstream.c
@@ -37,6 +37,7 @@
#include "gioerror.h"
#include "gcancellable.h"
#include "glocalfileoutputstream.h"
+#include "gfileinfo.h"
#include "glocalfileinfo.h"
#ifdef G_OS_UNIX
@@ -590,10 +591,23 @@ _g_local_file_output_stream_open (const char *filename,
return G_FILE_OUTPUT_STREAM (stream);
}
+static gint
+mode_from_flags_or_info (GFileCreateFlags flags,
+ GFileInfo *reference_info)
+{
+ if (flags & G_FILE_CREATE_PRIVATE)
+ return 0600;
+ else if (reference_info && g_file_info_has_attribute (reference_info, "unix::mode"))
+ return g_file_info_get_attribute_uint32 (reference_info, "unix::mode") & (~S_IFMT);
+ else
+ return 0666;
+}
+
GFileOutputStream *
_g_local_file_output_stream_create (const char *filename,
gboolean readable,
GFileCreateFlags flags,
+ GFileInfo *reference_info,
GCancellable *cancellable,
GError **error)
{
@@ -605,10 +619,7 @@ _g_local_file_output_stream_create (const char *filename,
if (g_cancellable_set_error_if_cancelled (cancellable, error))
return NULL;
- if (flags & G_FILE_CREATE_PRIVATE)
- mode = 0600;
- else
- mode = 0666;
+ mode = mode_from_flags_or_info (flags, reference_info);
open_flags = O_CREAT | O_EXCL | O_BINARY;
if (readable)
@@ -769,6 +780,7 @@ handle_overwrite_open (const char *filename,
gboolean create_backup,
char **temp_filename,
GFileCreateFlags flags,
+ GFileInfo *reference_info,
GCancellable *cancellable,
GError **error)
{
@@ -780,10 +792,7 @@ handle_overwrite_open (const char *filename,
int res;
int mode;
- if (flags & G_FILE_CREATE_PRIVATE)
- mode = 0600;
- else
- mode = 0666;
+ 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 */
@@ -1104,6 +1113,7 @@ _g_local_file_output_stream_replace (const char *filename,
const char *etag,
gboolean create_backup,
GFileCreateFlags flags,
+ GFileInfo *reference_info,
GCancellable *cancellable,
GError **error)
{
@@ -1119,10 +1129,7 @@ _g_local_file_output_stream_replace (const char *filename,
temp_file = NULL;
- if (flags & G_FILE_CREATE_PRIVATE)
- mode = 0600;
- else
- mode = 0666;
+ mode = mode_from_flags_or_info (flags, reference_info);
sync_on_close = FALSE;
/* If the file doesn't exist, create it */
@@ -1137,8 +1144,9 @@ _g_local_file_output_stream_replace (const char *filename,
{
/* The file already exists */
fd = handle_overwrite_open (filename, readable, etag,
- create_backup, &temp_file,
- flags, cancellable, error);
+ create_backup, &temp_file,
+ flags, reference_info,
+ cancellable, error);
if (fd == -1)
return NULL;
diff --git a/gio/glocalfileoutputstream.h b/gio/glocalfileoutputstream.h
index 844eacb..b8f062a 100644
--- a/gio/glocalfileoutputstream.h
+++ b/gio/glocalfileoutputstream.h
@@ -67,6 +67,7 @@ GFileOutputStream * _g_local_file_output_stream_open (const char *file
GFileOutputStream * _g_local_file_output_stream_create (const char *filename,
gboolean readable,
GFileCreateFlags flags,
+ GFileInfo *reference_info,
GCancellable *cancellable,
GError **error);
GFileOutputStream * _g_local_file_output_stream_append (const char *filename,
@@ -78,6 +79,7 @@ GFileOutputStream * _g_local_file_output_stream_replace (const char *file
const char *etag,
gboolean create_backup,
GFileCreateFlags flags,
+ GFileInfo *reference_info,
GCancellable *cancellable,
GError **error);
[
Date Prev][
Date Next] [
Thread Prev][
Thread Next]
[
Thread Index]
[
Date Index]
[
Author Index]