From: Suraj Jitindar Singh sjitindarsingh@gmail.com
commit 6fbcdd59094ade30db63f32316e9502425d7b256 upstream.
Commit ddf35cf3764b ("powerpc: Use barrier_nospec in copy_from_user()") Added barrier_nospec before loading from user-controlled 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 pointer.
Fixes: ddf35cf3764b ("powerpc: Use barrier_nospec in copy_from_user()") Signed-off-by: Suraj Jitindar Singh sjitindarsingh@gmail.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/powerpc/include/asm/uaccess.h | 1 + 1 file changed, 1 insertion(+)
--- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -306,6 +306,7 @@ extern unsigned long __copy_tofrom_user( 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__ */