From fed2512a7ccc8fc4b8e1de22925d127e4caac300 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Fri, 13 Jul 2018 14:06:00 -0400 Subject: 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: Mimi Zohar Reviewed-by: Kees Cook Cc: Luis R. Rodriguez Cc: Matthew Garrett Signed-off-by: James Morris --- security/integrity/ima/ima_main.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'security/integrity') diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 71fecfef0939..e467664965e7 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -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; } -- cgit v1.2.3