From be31dfdfd75b172af3ddcfa7511cdc3bb7adb25e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 13 Oct 2021 16:55:48 +0200 Subject: [PATCH] x86/fpu: Use fpstate::size Make use of fpstate::size in various places which require the buffer size information for sanity checks or memcpy() sizing. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20211013145322.973518954@linutronix.de --- arch/x86/kernel/fpu/core.c | 13 ++++++------- arch/x86/kernel/fpu/signal.c | 7 +++---- 2 files changed, 9 insertions(+), 11 deletions(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index a8cc20e90751..cb48c80ce5e3 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -166,13 +166,12 @@ void fpu_swap_kvm_fpu(struct fpu *save, struct fpu *rstor, u64 restore_mask) fpregs_lock(); if (save) { - if (test_thread_flag(TIF_NEED_FPU_LOAD)) { - memcpy(&save->fpstate->regs, - ¤t->thread.fpu.fpstate->regs, - fpu_kernel_xstate_size); - } else { + struct fpstate *fpcur = current->thread.fpu.fpstate; + + if (test_thread_flag(TIF_NEED_FPU_LOAD)) + memcpy(&save->fpstate->regs, &fpcur->regs, fpcur->size); + else save_fpregs_to_fpstate(save); - } } if (rstor) { @@ -398,7 +397,7 @@ int fpu_clone(struct task_struct *dst) fpregs_lock(); if (test_thread_flag(TIF_NEED_FPU_LOAD)) { memcpy(&dst_fpu->fpstate->regs, &src_fpu->fpstate->regs, - fpu_kernel_xstate_size); + dst_fpu->fpstate->size); } else { save_fpregs_to_fpstate(dst_fpu); } diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index c54c2a3dda44..aa9329189864 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -313,15 +313,13 @@ retry: static bool __fpu_restore_sig(void __user *buf, void __user *buf_fx, bool ia32_fxstate) { - int state_size = fpu_kernel_xstate_size; struct task_struct *tsk = current; struct fpu *fpu = &tsk->thread.fpu; struct user_i387_ia32_struct env; + bool success, fx_only = false; union fpregs_state *fpregs; + unsigned int state_size; u64 user_xfeatures = 0; - bool fx_only = false; - bool success; - if (use_xsave()) { struct _fpx_sw_bytes fx_sw_user; @@ -334,6 +332,7 @@ static bool __fpu_restore_sig(void __user *buf, void __user *buf_fx, user_xfeatures = fx_sw_user.xfeatures; } else { user_xfeatures = XFEATURE_MASK_FPSSE; + state_size = fpu->fpstate->size; } if (likely(!ia32_fxstate)) {