[PATCH] powerpc: Add barrier_nospec to raw_copy_in_user()

Suraj Jitindar Singh sjitindarsingh at gmail.com
Wed Mar 6 12:10:38 AEDT 2019

Commit ddf35cf3764b ("powerpc: Use barrier_nospec in copy_from_user()")
Added barrier_nospec before loading from user-controller pointers.
The intention was to order the load from the potentially user-controlled
pointer vs a previous branch based on an access_ok() check or similar.

In order to achieve the same result, add a barrier_nospec to the
raw_copy_in_user() function before loading from such a user-controlled

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh at gmail.com>
 arch/powerpc/include/asm/uaccess.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index e3a731793ea2..bb615592d5bb 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -306,6 +306,7 @@ extern unsigned long __copy_tofrom_user(void __user *to,
 static inline unsigned long
 raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
+	barrier_nospec();
 	return __copy_tofrom_user(to, from, n);
 #endif /* __powerpc64__ */

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