kexec permits the loading and execution of arbitrary code in ring 0, which permits the modification of the running kernel. Prevent this if trusted_kernel is true. Signed-off-by: Matthew Garrett <matthew.garrett@xxxxxxxxxx> --- kernel/kexec.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/kexec.c b/kernel/kexec.c index 60bafbe..281ddd0 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -32,6 +32,7 @@ #include <linux/vmalloc.h> #include <linux/swap.h> #include <linux/syscore_ops.h> +#include <linux/security.h> #include <asm/page.h> #include <asm/uaccess.h> @@ -946,6 +947,9 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) return -EPERM; + if (get_trusted_kernel()) + return -EPERM; + /* * Verify we have a legal set of flags * This leaves us room for future extensions. -- 1.8.5.3 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
