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powerpc: Add barrier_nospec to raw_copy_in_user() 

Commit ddf35cf376 ("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: ddf35cf376 ("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>
This commit is contained in:
Suraj Jitindar Singh 2019-03-06 12:10:38 +11:00 committed by Michael Ellerman
parent 3fefd1cd95
commit 6fbcdd5909
1 changed files with 1 additions and 0 deletions
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arch/powerpc/include/asm/uaccess.h
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@ -312,6 +312,7 @@ raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
{ {
unsigned long ret; unsigned long ret;
barrier_nospec();
allow_user_access(to, from, n); allow_user_access(to, from, n);
ret = __copy_tofrom_user(to, from, n); ret = __copy_tofrom_user(to, from, n);
prevent_user_access(to, from, n); prevent_user_access(to, from, n);