Commit 6fbcdd59 authored Mar 06, 2019 by Suraj Jitindar Singh Committed by Michael Ellerman Jul 03, 2019

powerpc: Add barrier_nospec to raw_copy_in_user()



Commit ddf35cf3 ("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: ddf35cf3 ("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>

parent 3fefd1cd

arch/powerpc/include/asm/uaccess.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -312,6 +312,7 @@ raw_copy_in_user(void __user to, const void __user from, unsigned long n)
		{
		unsigned long ret;

		barrier_nospec();
		allow_user_access(to, from, n);
		ret = __copy_tofrom_user(to, from, n);
		prevent_user_access(to, from, n);

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