fixes the cgsnapshot problem with pfile permisssions

cgpconfigparser changes the permissions of all files. That's why to test whether the variable file is writable, there have to be used the variable file from the root group.

  CHANGELOG:
	* add the information why root group is used for finding which variable is writable

Signed-off-by: Ivana Hutarova Varekova<varekova@redhat.com>
Signed-off-by: Jan Safranek <jsafrane@redhat.com>

diff --git a/src/tools/cgsnapshot.c b/src/tools/cgsnapshot.c
index a593f91a747b1b3c8222ee8f8fa0c4643fc40a58..f347b39341421679ea3d4713f4d69b221967366f 100644 (file)
--- a/src/tools/cgsnapshot.c
+++ b/src/tools/cgsnapshot.c
@@ -273,7 +273,7 @@ static int display_permissions(const char *path,
 
 static int display_cgroup_data(struct cgroup *group,
                char controller[CG_CONTROLLER_MAX][FILENAME_MAX],
-               const char *group_path, int first,
+               const char *group_path, int root_path_len, int first,
                const char *program_name)
 {
        int i = 0, j;
@@ -315,8 +315,14 @@ static int display_cgroup_data(struct cgroup *group,
                for (j = 0; j < nr_var; j++) {
                        name = cgroup_get_value_name(group_controller, j);
 
-                       /* test whether the variable file is writable */
-                       strncpy(var_path, group_path, FILENAME_MAX);
+                       /* For the non-root groups cgconfigparser set
+                          permissions of variable files to 777. Thus
+                          It is necessary to test the permissions of
+                          variable files in the root group to find out
+                          whether the variable is writable.
+                        */
+                       strncpy(var_path, group_path, root_path_len);
+                       var_path[root_path_len] = '\0';
                        strncat(var_path, "/", FILENAME_MAX);
                        var_path[FILENAME_MAX-1] = '\0';
                        strncat(var_path, name, FILENAME_MAX);
@@ -450,7 +456,7 @@ static int display_controller_data(
                        }
 
                        display_cgroup_data(group, controller, info.full_path,
-                               first, program_name);
+                               prefix_len, first, program_name);
                        first = 0;
                }
        }