From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id A9DBB6B0269 for ; Fri, 29 Jun 2018 18:41:42 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id u130-v6so4478136pgc.0 for ; Fri, 29 Jun 2018 15:41:42 -0700 (PDT) Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com. [115.124.30.131]) by mx.google.com with ESMTPS id v12-v6si10721204plo.264.2018.06.29.15.41.40 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 29 Jun 2018 15:41:41 -0700 (PDT) From: Yang Shi Subject: [RFC v3 PATCH 5/5] x86: check VM_DEAD flag in page fault Date: Sat, 30 Jun 2018 06:39:45 +0800 Message-Id: <1530311985-31251-6-git-send-email-yang.shi@linux.alibaba.com> In-Reply-To: <1530311985-31251-1-git-send-email-yang.shi@linux.alibaba.com> References: <1530311985-31251-1-git-send-email-yang.shi@linux.alibaba.com> Sender: owner-linux-mm@kvack.org List-ID: To: mhocko@kernel.org, willy@infradead.org, ldufour@linux.vnet.ibm.com, akpm@linux-foundation.org, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, alexander.shishkin@linux.intel.com, jolsa@redhat.com, namhyung@kernel.org, tglx@linutronix.de, hpa@zytor.com Cc: yang.shi@linux.alibaba.com, linux-mm@kvack.org, x86@kernel.org, linux-kernel@vger.kernel.org Check VM_DEAD flag of vma in page fault handler, if it is set, trigger SIGSEGV. Cc: Michal Hocko Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Signed-off-by: Yang Shi --- arch/x86/mm/fault.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 9a84a0d..3fd2da5 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1357,6 +1357,10 @@ static inline bool smap_violation(int error_code, struct pt_regs *regs) bad_area(regs, error_code, address); return; } + if (unlikely(vma->vm_flags & VM_DEAD)) { + bad_area(regs, error_code, address); + return; + } if (error_code & X86_PF_USER) { /* * Accessing the stack below %sp is always a bug. -- 1.8.3.1