[PATCH v2 09/11] s390/uaccess: Enable hardened usercopy

Kees Cook
2016-07-13T21:58:34Z

Enables CONFIG_HARDENED_USERCOPY checks on s390.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
arch/s390/Kconfig | 1 +
arch/s390/lib/uaccess.c | 2 ++
2 files changed, 3 insertions(+)

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);
--
2.7.4