From: Yang Zhong yang.zhong@intel.com
commit 063452fd94d153d4eb38ad58f210f3d37a09cca4 upstream.
ARCH_REQ_XCOMP_PERM is supposed to add the requested feature to the permission bitmap of thread_group_leader()->fpu. But the code overwrites the bitmap with the requested feature bit only rather than adding it.
Fix the code to add the requested feature bit to the master bitmask.
Fixes: db8268df0983 ("x86/arch_prctl: Add controls for dynamic XSTATE components") Signed-off-by: Yang Zhong yang.zhong@intel.com Signed-off-by: Chang S. Bae chang.seok.bae@intel.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: Paolo Bonzini bonzini@gnu.org Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220129173647.27981-2-chang.seok.bae@intel.com [chang: Backport for 5.16] Signed-off-by: Chang S. Bae chang.seok.bae@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kernel/fpu/xstate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1626,7 +1626,7 @@ static int __xstate_request_perm(u64 per return ret;
/* Pairs with the READ_ONCE() in xstate_get_group_perm() */ - WRITE_ONCE(fpu->perm.__state_perm, requested); + WRITE_ONCE(fpu->perm.__state_perm, mask); /* Protected by sighand lock */ fpu->perm.__state_size = ksize; fpu->perm.__user_state_size = usize;