livepatch: Disallow vmlinux.ko

This is purely a theoretical issue, but if there were a module named vmlinux.ko, the livepatch relocation code wouldn't be able to distinguish between vmlinux-specific and vmlinux.o-specific KLP relocations. If CONFIG_LIVEPATCH is enabled, don't allow a module named vmlinux.ko. Suggested-by: Peter Zijlstra <[email protected]> Signed-off-by: Josh Poimboeuf <[email protected]> Acked-by: Miroslav Benes <[email protected]> Acked-by: Joe Lawrence <[email protected]> Signed-off-by: Jiri Kosina <[email protected]>
kawasaki · May 7, 2020 · dcf550e · dcf550e
1 parent a811c1f
commit dcf550e
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
@@ -1139,6 +1139,11 @@ int klp_module_coming(struct module *mod)
 	if (WARN_ON(mod->state != MODULE_STATE_COMING))
 		return -EINVAL;
 
+	if (!strcmp(mod->name, "vmlinux")) {
+		pr_err("vmlinux.ko: invalid module name");
+		return -EINVAL;
+	}
+
 	mutex_lock(&klp_mutex);
 	/*
 	 * Each module has to know that klp_module_coming()