From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC5FCC10F11 for ; Sat, 13 Apr 2019 21:01:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 870162084E for ; Sat, 13 Apr 2019 21:01:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727250AbfDMVBx (ORCPT ); Sat, 13 Apr 2019 17:01:53 -0400 Received: from terminus.zytor.com ([198.137.202.136]:34953 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726964AbfDMVBx (ORCPT ); Sat, 13 Apr 2019 17:01:53 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x3DL1UME2267456 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Sat, 13 Apr 2019 14:01:30 -0700 Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x3DL1Uev2267453; Sat, 13 Apr 2019 14:01:30 -0700 Date: Sat, 13 Apr 2019 14:01:30 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Sebastian Andrzej Siewior Message-ID: Cc: rkrcmar@redhat.com, hpa@zytor.com, mingo@redhat.com, bigeasy@linutronix.de, tglx@linutronix.de, dave.hansen@intel.com, bp@suse.de, pbonzini@redhat.com, luto@kernel.org, jannh@google.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, riel@surriel.com, Jason@zx2c4.com, mingo@kernel.org Reply-To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, x86@kernel.org, riel@surriel.com, Jason@zx2c4.com, mingo@kernel.org, rkrcmar@redhat.com, hpa@zytor.com, mingo@redhat.com, bigeasy@linutronix.de, tglx@linutronix.de, dave.hansen@intel.com, bp@suse.de, luto@kernel.org, pbonzini@redhat.com, jannh@google.com In-Reply-To: <20190403164156.19645-23-bigeasy@linutronix.de> References: <20190403164156.19645-23-bigeasy@linutronix.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/fpu] x86/fpu: Merge the two code paths in __fpu__restore_sig() Git-Commit-ID: c2ff9e9a3d9d6c019394a22989a228d02970a8b1 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: c2ff9e9a3d9d6c019394a22989a228d02970a8b1 Gitweb: https://git.kernel.org/tip/c2ff9e9a3d9d6c019394a22989a228d02970a8b1 Author: Sebastian Andrzej Siewior AuthorDate: Wed, 3 Apr 2019 18:41:51 +0200 Committer: Borislav Petkov CommitDate: Fri, 12 Apr 2019 15:41:25 +0200 x86/fpu: Merge the two code paths in __fpu__restore_sig() The ia32_fxstate case (32bit with fxsr) and the other (64bit frames or 32bit frames without fxsr) restore both from kernel memory and sanitize the content. The !ia32_fxstate version restores missing xstates from "init state" while the ia32_fxstate doesn't and skips it. Merge the two code paths and keep the !ia32_fxstate one. Copy only the user_i387_ia32_struct data structure in the ia32_fxstate. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Borislav Petkov Reviewed-by: Dave Hansen Reviewed-by: Thomas Gleixner Cc: Andy Lutomirski Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Jann Horn Cc: "Jason A. Donenfeld" Cc: kvm ML Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Rik van Riel Cc: x86-ml Link: https://lkml.kernel.org/r/20190403164156.19645-23-bigeasy@linutronix.de --- arch/x86/kernel/fpu/signal.c | 139 +++++++++++++++++-------------------------- 1 file changed, 54 insertions(+), 85 deletions(-) diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c index 9ea1eaa4c9b1..b13e86b29426 100644 --- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -263,12 +263,17 @@ static inline int copy_user_to_fpregs_zeroing(void __user *buf, u64 xbv, int fx_ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) { + struct user_i387_ia32_struct *envp = NULL; + int state_size = fpu_kernel_xstate_size; int ia32_fxstate = (buf != buf_fx); struct task_struct *tsk = current; struct fpu *fpu = &tsk->thread.fpu; - int state_size = fpu_kernel_xstate_size; + struct user_i387_ia32_struct env; + union fpregs_state *state; u64 xfeatures = 0; int fx_only = 0; + int ret = 0; + void *tmp; ia32_fxstate &= (IS_ENABLED(CONFIG_X86_32) || IS_ENABLED(CONFIG_IA32_EMULATION)); @@ -303,105 +308,69 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size) } } + tmp = kzalloc(sizeof(*state) + fpu_kernel_xstate_size + 64, GFP_KERNEL); + if (!tmp) + return -ENOMEM; + state = PTR_ALIGN(tmp, 64); + + if ((unsigned long)buf_fx % 64) + fx_only = 1; + + /* + * For 32-bit frames with fxstate, copy the fxstate so it can be + * reconstructed later. + */ if (ia32_fxstate) { - /* - * For 32-bit frames with fxstate, copy the user state to the - * thread's fpu state, reconstruct fxstate from the fsave - * header. Validate and sanitize the copied state. - */ - struct user_i387_ia32_struct env; - union fpregs_state *state; - int err = 0; - void *tmp; + ret = __copy_from_user(&env, buf, sizeof(env)); + if (ret) + goto err_out; + envp = &env; + } - tmp = kzalloc(sizeof(*state) + fpu_kernel_xstate_size + 64, GFP_KERNEL); - if (!tmp) - return -ENOMEM; - state = PTR_ALIGN(tmp, 64); + if (use_xsave() && !fx_only) { + u64 init_bv = xfeatures_mask & ~xfeatures; if (using_compacted_format()) { - err = copy_user_to_xstate(&state->xsave, buf_fx); + ret = copy_user_to_xstate(&state->xsave, buf_fx); } else { - err = __copy_from_user(&state->xsave, buf_fx, state_size); + ret = __copy_from_user(&state->xsave, buf_fx, state_size); - if (!err && state_size > offsetof(struct xregs_state, header)) - err = validate_xstate_header(&state->xsave.header); + if (!ret && state_size > offsetof(struct xregs_state, header)) + ret = validate_xstate_header(&state->xsave.header); } + if (ret) + goto err_out; - if (err || __copy_from_user(&env, buf, sizeof(env))) { - err = -1; - } else { - sanitize_restored_xstate(state, &env, xfeatures, fx_only); - copy_kernel_to_fpregs(state); - } - - kfree(tmp); - return err; - } else { - union fpregs_state *state; - void *tmp; - int ret; - - tmp = kzalloc(sizeof(*state) + fpu_kernel_xstate_size + 64, GFP_KERNEL); - if (!tmp) - return -ENOMEM; - state = PTR_ALIGN(tmp, 64); - - /* - * For 64-bit frames and 32-bit fsave frames, restore the user - * state to the registers directly (with exceptions handled). - */ - if ((unsigned long)buf_fx % 64) - fx_only = 1; - - if (use_xsave() && !fx_only) { - u64 init_bv = xfeatures_mask & ~xfeatures; - - if (using_compacted_format()) { - ret = copy_user_to_xstate(&state->xsave, buf_fx); - } else { - ret = __copy_from_user(&state->xsave, buf_fx, state_size); - - if (!ret && state_size > offsetof(struct xregs_state, header)) - ret = validate_xstate_header(&state->xsave.header); - } - if (ret) - goto err_out; - - sanitize_restored_xstate(state, NULL, xfeatures, fx_only); - - if (unlikely(init_bv)) - copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); - ret = copy_kernel_to_xregs_err(&state->xsave, xfeatures); + sanitize_restored_xstate(state, envp, xfeatures, fx_only); - } else if (use_fxsr()) { - ret = __copy_from_user(&state->fxsave, buf_fx, state_size); - if (ret) - goto err_out; + if (unlikely(init_bv)) + copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); + ret = copy_kernel_to_xregs_err(&state->xsave, xfeatures); - if (use_xsave()) { - u64 init_bv = xfeatures_mask & ~XFEATURE_MASK_FPSSE; - copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); - } - state->fxsave.mxcsr &= mxcsr_feature_mask; + } else if (use_fxsr()) { + ret = __copy_from_user(&state->fxsave, buf_fx, state_size); + if (ret) + goto err_out; - ret = copy_kernel_to_fxregs_err(&state->fxsave); - } else { - ret = __copy_from_user(&state->fsave, buf_fx, state_size); - if (ret) - goto err_out; - ret = copy_kernel_to_fregs_err(&state->fsave); + sanitize_restored_xstate(state, envp, xfeatures, fx_only); + if (use_xsave()) { + u64 init_bv = xfeatures_mask & ~XFEATURE_MASK_FPSSE; + copy_kernel_to_xregs(&init_fpstate.xsave, init_bv); } -err_out: - kfree(tmp); - if (ret) { - fpu__clear(fpu); - return -1; - } + ret = copy_kernel_to_fxregs_err(&state->fxsave); + } else { + ret = __copy_from_user(&state->fsave, buf_fx, state_size); + if (ret) + goto err_out; + ret = copy_kernel_to_fregs_err(&state->fsave); } - return 0; +err_out: + kfree(tmp); + if (ret) + fpu__clear(fpu); + return ret; } static inline int xstate_sigframe_size(void)