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Commit fed2512a authored by Mimi Zohar's avatar Mimi Zohar Committed by James Morris
Browse files

ima: based on policy require signed firmware (sysfs fallback) 



With an IMA policy requiring signed firmware, this patch prevents
the sysfs fallback method of loading firmware.

Signed-off-by: default avatarMimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Matthew Garrett <mjg59@google.com>
Signed-off-by: default avatarJames Morris <james.morris@microsoft.com>
parent 6e852651

security/integrity/ima/ima_main.c

+9 −1
Original line number Diff line number Diff line
@@ -472,8 +472,10 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, 


	if (!file && read_id == READING_FIRMWARE) {

		if ((ima_appraise & IMA_APPRAISE_FIRMWARE) &&

		    (ima_appraise & IMA_APPRAISE_ENFORCE))

		    (ima_appraise & IMA_APPRAISE_ENFORCE)) {

			pr_err("Prevent firmware loading_store.\n");

			return -EACCES;	/* INTEGRITY_UNKNOWN */

		}

		return 0;

	}
@@ -517,6 +519,12 @@ int ima_load_data(enum kernel_load_data_id id) 
			pr_err("impossible to appraise a kernel image without a file descriptor; try using kexec_file_load syscall.\n");

			return -EACCES;	/* INTEGRITY_UNKNOWN */

		}

		break;

	case LOADING_FIRMWARE:

		if (ima_appraise & IMA_APPRAISE_FIRMWARE) {

			pr_err("Prevent firmware sysfs fallback loading.\n");

			return -EACCES;	/* INTEGRITY_UNKNOWN */

		}

	default:

		break;

	}