s390/uaccess: Enable hardened usercopy

Enables CONFIG_HARDENED_USERCOPY checks on s390.

Signed-off-by: Kees Cook <keescook@chromium.org>

2 files changed, 3 insertions, 0 deletions

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index a8c259059adf..9f694311c9ed 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -122,6 +122,7 @@ config S390
         select HAVE_ALIGNED_STRUCT_PAGE if SLUB
         select HAVE_ARCH_AUDITSYSCALL
         select HAVE_ARCH_EARLY_PFN_TO_NID
+        select HAVE_ARCH_HARDENED_USERCOPY
         select HAVE_ARCH_JUMP_LABEL
         select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
         select HAVE_ARCH_SECCOMP_FILTER
diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c
index ae4de559e3a0..6986c20166f0 100644
--- a/arch/s390/lib/uaccess.c
+++ b/arch/s390/lib/uaccess.c
@@ -104,6 +104,7 @@ static inline unsigned long copy_from_user_mvcp(void *x, const void __user *ptr,
 
 unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n)
 {
+        check_object_size(to, n, false);
         if (static_branch_likely(&have_mvcos))
                 return copy_from_user_mvcos(to, from, n);
         return copy_from_user_mvcp(to, from, n);
@@ -177,6 +178,7 @@ static inline unsigned long copy_to_user_mvcs(void __user *ptr, const void *x,
 
 unsigned long __copy_to_user(void __user *to, const void *from, unsigned long n)
 {
+        check_object_size(from, n, true);
         if (static_branch_likely(&have_mvcos))
                 return copy_to_user_mvcos(to, from, n);
         return copy_to_user_mvcs(to, from, n);