s390/uaccess: Enable hardened usercopy

Enables CONFIG_HARDENED_USERCOPY checks on s390.

Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit 97433ea4fda62349bfa42089455593cbcb57e06c)
Signed-off-by: Alex Shi <alex.shi@linaro.org>

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 3a55f493c7da72b9ee7ee7ad7c8c76d9e01bed8d..60530fd93d6d11368731fedfe145afb6826c7e59 100644 (file)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -117,6 +117,7 @@ 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 HAVE_ARCH_SECCOMP_FILTER
        select HAVE_ARCH_SOFT_DIRTY

diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c
index ae4de559e3a04288c6be111de684b3355f35109b..6986c20166f028bd859fa38af033d076a93eb3f3 100644 (file)
--- 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);