Merge tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull usercopy protection from Kees Cook:
 "Tbhis implements HARDENED_USERCOPY verification of copy_to_user and
  copy_from_user bounds checking for most architectures on SLAB and
  SLUB"

* tag 'usercopy-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  mm: SLUB hardened usercopy support
  mm: SLAB hardened usercopy support
  s390/uaccess: Enable hardened usercopy
  sparc/uaccess: Enable hardened usercopy
  powerpc/uaccess: Enable hardened usercopy
  ia64/uaccess: Enable hardened usercopy
  arm64/uaccess: Enable hardened usercopy
  ARM: uaccess: Enable hardened usercopy
  x86/uaccess: Enable hardened usercopy
  mm: Hardened usercopy
  mm: Implement stack frame object validation
  mm: Add is_migrate_cma_page

3 files changed, 38 insertions, 0 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index f2e4e90621ec..d572b78b65e1 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -68,8 +68,10 @@ extern char * const migratetype_names[MIGRATE_TYPES];
 
 #ifdef CONFIG_CMA
 #  define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
+#  define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)
 #else
 #  define is_migrate_cma(migratetype) false
+#  define is_migrate_cma_page(_page) false
 #endif
 
 #define for_each_migratetype_order(order, type) \
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 1a4ea551aae5..4293808d8cfb 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -155,6 +155,18 @@ void kfree(const void *);
 void kzfree(const void *);
 size_t ksize(const void *);
 
+#ifdef CONFIG_HAVE_HARDENED_USERCOPY_ALLOCATOR
+const char *__check_heap_object(const void *ptr, unsigned long n,
+				struct page *page);
+#else
+static inline const char *__check_heap_object(const void *ptr,
+					      unsigned long n,
+					      struct page *page)
+{
+	return NULL;
+}
+#endif
+
 /*
  * Some archs want to perform DMA into kmalloc caches and need a guaranteed
  * alignment larger than the alignment of a 64-bit integer.
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index 352b1542f5cc..cbd8990e2e77 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -105,6 +105,30 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 
 #define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED)
 
+#ifndef CONFIG_HAVE_ARCH_WITHIN_STACK_FRAMES
+static inline int arch_within_stack_frames(const void * const stack,
+					   const void * const stackend,
+					   const void *obj, unsigned long len)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_HARDENED_USERCOPY
+extern void __check_object_size(const void *ptr, unsigned long n,
+					bool to_user);
+
+static inline void check_object_size(const void *ptr, unsigned long n,
+				     bool to_user)
+{
+	__check_object_size(ptr, n, to_user);
+}
+#else
+static inline void check_object_size(const void *ptr, unsigned long n,
+				     bool to_user)
+{ }
+#endif /* CONFIG_HARDENED_USERCOPY */
+
 #endif	/* __KERNEL__ */
 
 #endif /* _LINUX_THREAD_INFO_H */