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

1 files changed, 6 insertions, 4 deletions

diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 52f230094c51..a0ae610b9280 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -761,9 +761,10 @@ copy_from_user(void *to, const void __user *from, unsigned long n)
 	 * case, and do only runtime checking for non-constant sizes.
 	 */
 
-	if (likely(sz < 0 || sz >= n))
+	if (likely(sz < 0 || sz >= n)) {
+		check_object_size(to, n, false);
 		n = _copy_from_user(to, from, n);
-	else if(__builtin_constant_p(n))
+	} else if (__builtin_constant_p(n))
 		copy_from_user_overflow();
 	else
 		__copy_from_user_overflow(sz, n);
@@ -781,9 +782,10 @@ copy_to_user(void __user *to, const void *from, unsigned long n)
 	might_fault();
 
 	/* See the comment in copy_from_user() above. */
-	if (likely(sz < 0 || sz >= n))
+	if (likely(sz < 0 || sz >= n)) {
+		check_object_size(from, n, true);
 		n = _copy_to_user(to, from, n);
-	else if(__builtin_constant_p(n))
+	} else if (__builtin_constant_p(n))
 		copy_to_user_overflow();
 	else
 		__copy_to_user_overflow(sz, n);