4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

Commit a1d09e074250fad24f1b993f327b18cc6812eb7a upstream.

Sanitize user pointer given to __copy_to_user, both for standard version
and memcopy version of the user accessor.

Signed-off-by: Julien Thierry <julien.thie...@arm.com>
Signed-off-by: Russell King <rmk+ker...@armlinux.org.uk>
Signed-off-by: David A. Long <dave.l...@linaro.org>
Reviewed-by: Julien Thierry <julien.thie...@arm.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 arch/arm/lib/copy_to_user.S        | 6 +++++-
 arch/arm/lib/uaccess_with_memcpy.c | 3 ++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm/lib/copy_to_user.S b/arch/arm/lib/copy_to_user.S
index caf5019d8161..970abe521197 100644
--- a/arch/arm/lib/copy_to_user.S
+++ b/arch/arm/lib/copy_to_user.S
@@ -94,6 +94,11 @@
 
 ENTRY(__copy_to_user_std)
 WEAK(arm_copy_to_user)
+#ifdef CONFIG_CPU_SPECTRE
+       get_thread_info r3
+       ldr     r3, [r3, #TI_ADDR_LIMIT]
+       uaccess_mask_range_ptr r0, r2, r3, ip
+#endif
 
 #include "copy_template.S"
 
@@ -108,4 +113,3 @@ ENDPROC(__copy_to_user_std)
        rsb     r0, r0, r2
        copy_abort_end
        .popsection
-
diff --git a/arch/arm/lib/uaccess_with_memcpy.c 
b/arch/arm/lib/uaccess_with_memcpy.c
index 6bd1089b07e0..f598d792bace 100644
--- a/arch/arm/lib/uaccess_with_memcpy.c
+++ b/arch/arm/lib/uaccess_with_memcpy.c
@@ -152,7 +152,8 @@ arm_copy_to_user(void __user *to, const void *from, 
unsigned long n)
                n = __copy_to_user_std(to, from, n);
                uaccess_restore(ua_flags);
        } else {
-               n = __copy_to_user_memcpy(to, from, n);
+               n = __copy_to_user_memcpy(uaccess_mask_range_ptr(to, n),
+                                         from, n);
        }
        return n;
 }
-- 
2.19.1



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