From 9ba589f9cdbd8906465b108bc7ec0fc1519a06d3 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 23 Jun 2021 14:02:26 +0200 Subject: [PATCH] x86/fpu/signal: Remove the legacy alignment check Checking for the XSTATE buffer being 64-byte aligned, and if not, deciding just to restore the FXSR state is daft. If user space provides an unaligned math frame and has the extended state magic set in the FX software reserved bytes, then it really can keep the pieces. If the frame is unaligned and the FX software magic is not set, then fx_only is already set and the restore will use fxrstor. Remove it. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Reviewed-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210623121457.184149902@linutronix.de --- arch/x86/kernel/fpu/signal.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index 42e85c3..8a327c0 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -306,9 +306,6 @@ static int __fpu_restore_sig(void __user *buf, void __user *buf_fx, } } - if ((unsigned long)buf_fx % 64) - fx_only = 1; - if (!ia32_fxstate) { /* * Attempt to restore the FPU registers directly from user -- 2.7.4