ima: check signature enforcement against cmdline param instead of CONFIG

When the user requests MODULE_CHECK policy and its kernel is compiled
with CONFIG_MODULE_SIG_FORCE not set, all modules would not load, just
those loaded in initram time. One option the user would have would be
set a kernel cmdline param (module.sig_enforce) to true, but the IMA
module check code doesn't rely on this value, it checks just
CONFIG_MODULE_SIG_FORCE.

This patch solves this problem checking for the exported value of
module.sig_enforce cmdline param intead of CONFIG_MODULE_SIG_FORCE,
which holds the effective value (CONFIG || param).

Signed-off-by: Bruno E. O. Meneguele <brdeoliv@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This commit is contained in:
Bruno E. O. Meneguele 2017-10-24 15:37:01 -02:00 committed by Mimi Zohar
parent fda784e50a
commit 7c9bc0983f
1 changed files with 3 additions and 3 deletions

View File

@ -362,12 +362,12 @@ void ima_post_path_mknod(struct dentry *dentry)
*/
int ima_read_file(struct file *file, enum kernel_read_file_id read_id)
{
bool sig_enforce = is_module_sig_enforced();
if (!file && read_id == READING_MODULE) {
#ifndef CONFIG_MODULE_SIG_FORCE
if ((ima_appraise & IMA_APPRAISE_MODULES) &&
if (!sig_enforce && (ima_appraise & IMA_APPRAISE_MODULES) &&
(ima_appraise & IMA_APPRAISE_ENFORCE))
return -EACCES; /* INTEGRITY_UNKNOWN */
#endif
return 0; /* We rely on module signature checking */
}
return 0;