On 1/10/20 1:09 PM, Richard Haines wrote:
On Thu, 2020-01-09 at 12:19 -0500, Stephen Smalley wrote:
On 1/9/20 10:07 AM, Richard Haines wrote:
Test filesystem permissions and setfscreatecon(3).
From kernels 5.5 filesystem { watch } is also tested.
Signed-off-by: Richard Haines <richard_c_haines@xxxxxxxxxxxxxx>
---
diff --git a/policy/test_filesystem.te b/policy/test_filesystem.te
new file mode 100644
index 0000000..2eee1fc
--- /dev/null
+++ b/policy/test_filesystem.te
@@ -0,0 +1,324 @@
+#
+######### Test filesystem permissions policy module ##########
+#
+attribute filesystemdomain;
+
+#################### Create a test file context
######################
+type test_filesystem_filecon_t;
+unconfined_runs_test(test_filesystem_filecon_t)
+
+################# Test all functions ##########################
+type test_filesystem_t;
+domain_type(test_filesystem_t)
+unconfined_runs_test(test_filesystem_t)
+typeattribute test_filesystem_t testdomain;
+typeattribute test_filesystem_t filesystemdomain;
+
+allow test_filesystem_t self:capability { sys_admin };
+allow test_filesystem_t self:filesystem { mount remount quotamod
relabelfrom relabelto unmount quotaget };
+allow test_filesystem_t self:dir { mounton add_name write };
+allow test_filesystem_t test_file_t:dir { mounton write
remove_name rmdir };
+# Create test file
+allow test_filesystem_t self:dir { add_name write };
+allow test_filesystem_t self:file { create relabelfrom relabelto
};
+
+fs_mount_all_fs(test_filesystem_t)
+fs_remount_all_fs(test_filesystem_t)
+fs_unmount_all_fs(test_filesystem_t)
+fs_relabelfrom_all_fs(test_filesystem_t)
+fs_get_xattr_fs_quotas(test_filesystem_t)
+files_search_all(test_filesystem_t)
+# Required for mount opts
"rootcontext=system_u:object_r:test_filesystem_t:s0";
+fs_associate(test_filesystem_t)
+fs_getattr_xattr_fs(test_filesystem_t)
+
+# For running quotacheck(8)
+files_type(test_filesystem_t)
+# Update quotas
+fs_set_all_quotas(test_filesystem_t)
+allow test_filesystem_t self:file { quotaon };
+# Create test file and change context:
+fs_associate(test_filesystem_filecon_t)
+allow test_filesystem_t test_filesystem_filecon_t:file { open read
getattr relabelto write };
+dontaudit test_filesystem_t kernel_t:process { setsched };
Why do you need these dontaudit statements? It seems like a kernel
bug
if something is triggering a setsched permission check on the
kernel_t
domain? Something the kernel module is doing during initialization?
I've tracked this down to them all being called from block/ioprio.c
with: security_task_setioprio(task, ioprio) -> selinux_task_setioprio
Why the SECCLASS_PROCESS, PROCESS__SETSCHED I've no idea. The following
also use SET/GETSCHED permission:
selinux_task_getioprio, selinux_task_setnice, selinux_task_movememory
The confusing bit is that it is between test_filesystem_t and kernel_t.
If the process was setting its own ioprio, then I'd expect to see the
denial between test_filesystem_t and test_filesystem_t aka self. If the
process inserted a kernel module and the module initializer spawned a
kernel thread that set its ioprio, I would expect it to be kernel_t to
kernel_t.
