From 13752fe2d7f2d41c2fd92a5d1b1c6e38c4de0c05 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 25 Feb 2014 10:28:04 -0800 Subject: security: introduce kernel_fw_from_file hook In order to validate the contents of firmware being loaded, there must be a hook to evaluate any loaded firmware that wasn't built into the kernel itself. Without this, there is a risk that a root user could load malicious firmware designed to mount an attack against kernel memory (e.g. via DMA). Signed-off-by: Kees Cook Reviewed-by: Takashi Iwai --- security/capability.c | 6 ++++++ security/security.c | 6 ++++++ 2 files changed, 12 insertions(+) (limited to 'security') diff --git a/security/capability.c b/security/capability.c index e76373de3129..a74fde6a7468 100644 --- a/security/capability.c +++ b/security/capability.c @@ -401,6 +401,11 @@ static int cap_kernel_create_files_as(struct cred *new, struct inode *inode) return 0; } +static int cap_kernel_fw_from_file(struct file *file, char *buf, size_t size) +{ + return 0; +} + static int cap_kernel_module_request(char *kmod_name) { return 0; @@ -1015,6 +1020,7 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, cred_transfer); set_to_cap_if_null(ops, kernel_act_as); set_to_cap_if_null(ops, kernel_create_files_as); + set_to_cap_if_null(ops, kernel_fw_from_file); set_to_cap_if_null(ops, kernel_module_request); set_to_cap_if_null(ops, kernel_module_from_file); set_to_cap_if_null(ops, task_fix_setuid); diff --git a/security/security.c b/security/security.c index 31614e9e96e5..35d37d0f0d49 100644 --- a/security/security.c +++ b/security/security.c @@ -845,6 +845,12 @@ int security_kernel_create_files_as(struct cred *new, struct inode *inode) return security_ops->kernel_create_files_as(new, inode); } +int security_kernel_fw_from_file(struct file *file, char *buf, size_t size) +{ + return security_ops->kernel_fw_from_file(file, buf, size); +} +EXPORT_SYMBOL_GPL(security_kernel_fw_from_file); + int security_kernel_module_request(char *kmod_name) { return security_ops->kernel_module_request(kmod_name); -- cgit v1.2.3