From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yu-cheng Yu Subject: [PATCH 07/10] mm: Prevent mprotect from changing shadow stack Date: Thu, 7 Jun 2018 07:38:04 -0700 Message-ID: <20180607143807.3611-8-yu-cheng.yu@intel.com> References: <20180607143807.3611-1-yu-cheng.yu@intel.com> Return-path: In-Reply-To: <20180607143807.3611-1-yu-cheng.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , "H.J. Lu" , Vedvyas Shanbhogue , "Ravi V. Shankar" , Dave Hansen , Andy Lutomirski , Jonathan Corbet , Oleg Nesterov , Arnd Bergmann , Mike Kravetz Cc: Yu-cheng Yu List-Id: linux-arch.vger.kernel.org Signed-off-by: Yu-cheng Yu --- mm/mprotect.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/mprotect.c b/mm/mprotect.c index 625608bc8962..128dcb880c12 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -446,6 +446,15 @@ static int do_mprotect_pkey(unsigned long start, size_t len, error = -ENOMEM; if (!vma) goto out; + + /* + * Do not allow changing shadow stack memory. + */ + if (vma->vm_flags & VM_SHSTK) { + error = -EINVAL; + goto out; + } + prev = vma->vm_prev; if (unlikely(grows & PROT_GROWSDOWN)) { if (vma->vm_start >= end) -- 2.15.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga09.intel.com ([134.134.136.24]:36346 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934602AbeFGOlf (ORCPT ); Thu, 7 Jun 2018 10:41:35 -0400 From: Yu-cheng Yu Subject: [PATCH 07/10] mm: Prevent mprotect from changing shadow stack Date: Thu, 7 Jun 2018 07:38:04 -0700 Message-ID: <20180607143807.3611-8-yu-cheng.yu@intel.com> In-Reply-To: <20180607143807.3611-1-yu-cheng.yu@intel.com> References: <20180607143807.3611-1-yu-cheng.yu@intel.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , "H.J. Lu" , Vedvyas Shanbhogue , "Ravi V. Shankar" , Dave Hansen , Andy Lutomirski , Jonathan Corbet , Oleg Nesterov , Arnd Bergmann , Mike Kravetz Cc: Yu-cheng Yu Message-ID: <20180607143804.gYTaNTTmHlUnBRxCcwBZfGnm-zVVl3z4UbywFzCNrdQ@z> Signed-off-by: Yu-cheng Yu --- mm/mprotect.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/mprotect.c b/mm/mprotect.c index 625608bc8962..128dcb880c12 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -446,6 +446,15 @@ static int do_mprotect_pkey(unsigned long start, size_t len, error = -ENOMEM; if (!vma) goto out; + + /* + * Do not allow changing shadow stack memory. + */ + if (vma->vm_flags & VM_SHSTK) { + error = -EINVAL; + goto out; + } + prev = vma->vm_prev; if (unlikely(grows & PROT_GROWSDOWN)) { if (vma->vm_start >= end) -- 2.15.1