| From 063452fd94d153d4eb38ad58f210f3d37a09cca4 Mon Sep 17 00:00:00 2001 |
| From: Yang Zhong <yang.zhong@intel.com> |
| Date: Sat, 29 Jan 2022 09:36:46 -0800 |
| Subject: x86/fpu/xstate: Fix the ARCH_REQ_XCOMP_PERM implementation |
| |
| 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; |