Patches from Photon OS

kmod/patch/kpatch-patch-hook.c

@@ -24,6 +24,7 @@
 #include <linux/slab.h>
 #include <linux/kallsyms.h>
 #include "kpatch.h"
+#include <linux/livepatch.h>
 #include "kpatch-patch.h"
 
 static bool replace;

kmod/patch/kpatch-patch.h

@@ -22,6 +22,34 @@
 #ifndef _KPATCH_PATCH_H_
 #define _KPATCH_PATCH_H_
 
+#include <linux/version.h>
+
+/* Support for livepatch callbacks? */
+#ifdef RHEL_RELEASE_CODE
+# if RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(7, 5)
+#  define HAVE_CALLBACKS
+# endif
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 15, 0)
+# define HAVE_CALLBACKS
+#endif
+
+#ifdef HAVE_CALLBACKS
+/* IMPORTANT: include ordering is critical! */
+# ifdef _LINUX_LIVEPATCH_H_
+typedef struct klp_object klp_obj;
+# else
+/*
+ * Basically just a placeholder for when we can't include linux/livepatch.h.
+ * The correct type, which is what gets packed in the section, is
+ * struct klp_object.
+ */
+typedef void klp_obj;
+# endif /* _LINUX_LIVEPATCH_H_ */
+#else
+#include "kpatch.h"
+typedef struct kpatch_object klp_obj;
+#endif /* HAVE_CALLBACKS */
+
 struct kpatch_patch_func {
 	unsigned long new_addr;
 	unsigned long new_size;
@@ -43,20 +71,21 @@ struct kpatch_patch_dynrela {
 	long addend;
 };
 
+
 struct kpatch_pre_patch_callback {
-	int (*callback)(void *obj);
+	int (*callback)(klp_obj *obj);
 	char *objname;
 };
 struct kpatch_post_patch_callback {
-	void (*callback)(void *obj);
+	void (*callback)(klp_obj *obj);
 	char *objname;
 };
 struct kpatch_pre_unpatch_callback {
-	void (*callback)(void *obj);
+	void (*callback)(klp_obj *obj);
 	char *objname;
 };
 struct kpatch_post_unpatch_callback {
-	void (*callback)(void *obj);
+	void (*callback)(klp_obj *obj);
 	char *objname;
 };
 

kmod/patch/livepatch-patch-hook.c

@@ -1,6 +1,6 @@
 /*
  * Copyright (C) 2013-2014 Josh Poimboeuf <[email protected]>
- * Copyright (C) 2014 Seth Jennings <[email protected]> 
+ * Copyright (C) 2014 Seth Jennings <[email protected]>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -56,14 +56,6 @@
 # define HAVE_IMMEDIATE
 #endif
 
-#ifdef RHEL_RELEASE_CODE
-# if RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(7, 5)
-#  define HAVE_CALLBACKS
-# endif
-#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 15, 0)
-# define HAVE_CALLBACKS
-#endif
-
 #ifdef RHEL_RELEASE_CODE
 # if (RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(7, 8) && 		\
 	 RHEL_RELEASE_CODE < RHEL_RELEASE_VERSION(8, 0)) || 		\
@@ -356,8 +348,7 @@ static int add_callbacks_to_patch_objects(void)
 				object->name ? object->name : "vmlinux");
 			return -EINVAL;
 		}
-		object->callbacks.pre_patch = (int (*)(struct klp_object *))
-					       p_pre_patch_callback->callback;
+		object->callbacks.pre_patch = p_pre_patch_callback->callback;
 	}
 
 	for (p_post_patch_callback = __kpatch_callbacks_post_patch;
@@ -371,8 +362,7 @@ static int add_callbacks_to_patch_objects(void)
 				object->name ? object->name : "vmlinux");
 			return -EINVAL;
 		}
-		object->callbacks.post_patch = (void (*)(struct klp_object *))
-						p_post_patch_callback->callback;
+		object->callbacks.post_patch = p_post_patch_callback->callback;
 	}
 
 	for (p_pre_unpatch_callback = __kpatch_callbacks_pre_unpatch;
@@ -386,8 +376,7 @@ static int add_callbacks_to_patch_objects(void)
 				object->name ? object->name : "vmlinux");
 			return -EINVAL;
 		}
-		object->callbacks.pre_unpatch = (void (*)(struct klp_object *))
-						p_pre_unpatch_callback->callback;
+		object->callbacks.pre_unpatch = p_pre_unpatch_callback->callback;
 	}
 
 	for (p_post_unpatch_callback = __kpatch_callbacks_post_unpatch;
@@ -401,8 +390,7 @@ static int add_callbacks_to_patch_objects(void)
 				object->name ? object->name : "vmlinux");
 			return -EINVAL;
 		}
-		object->callbacks.post_unpatch = (void (*)(struct klp_object *))
-						p_post_unpatch_callback->callback;
+		object->callbacks.post_unpatch = p_post_unpatch_callback->callback;
 	}
 
 	return 0;

kpatch-build/create-diff-object.c

@@ -236,19 +236,19 @@ static struct rela *toc_rela(const struct rela *rela)
 static void kpatch_bundle_symbols(struct kpatch_elf *kelf)
 {
 	struct symbol *sym;
-	unsigned int expected_offset;
+	uint64_t expected_offset;
 
 	list_for_each_entry(sym, &kelf->symbols, list) {
 		if (is_bundleable(sym)) {
 			if (sym->pfx)
-				expected_offset = 16;
+				expected_offset = sym->pfx->sym.st_size;
 			else if (is_gcc6_localentry_bundled_sym(kelf, sym))
 				expected_offset = 8;
 			else
 				expected_offset = 0;
 
 			if (sym->sym.st_value != expected_offset) {
-				ERROR("symbol %s at offset %lu within section %s, expected %u",
+				ERROR("symbol %s at offset %lu within section %s, expected %lu",
 				      sym->name, sym->sym.st_value,
 				      sym->sec->name, expected_offset);
 			}

kpatch-build/kpatch-elf.c

@@ -470,7 +470,7 @@ static void kpatch_link_prefixed_functions(struct kpatch_elf *kelf)
 
 		list_for_each_entry(func, &kelf->symbols, list) {
 			if (func->type == STT_FUNC && func->sec == pfx->sec &&
-			    func->sym.st_value == pfx->sym.st_value + 16) {
+			    func->sym.st_value == pfx->sym.st_value + pfx->sym.st_size) {
 
 				/*
 				 * If a func has aliases, it's possible for