From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 8D7EF7D08C for ; Thu, 7 Jun 2018 15:42:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934995AbeFGPmF (ORCPT ); Thu, 7 Jun 2018 11:42:05 -0400 Received: from mga09.intel.com ([134.134.136.24]:36348 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934016AbeFGOlh (ORCPT ); Thu, 7 Jun 2018 10:41:37 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Jun 2018 07:41:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.49,486,1520924400"; d="scan'208";a="62632655" Received: from 2b52.sc.intel.com ([143.183.136.51]) by orsmga001.jf.intel.com with ESMTP; 07 Jun 2018 07:41:34 -0700 From: Yu-cheng Yu 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 Subject: [PATCH 09/10] mm: Prevent madvise from changing shadow stack Date: Thu, 7 Jun 2018 07:38:06 -0700 Message-Id: <20180607143807.3611-10-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180607143807.3611-1-yu-cheng.yu@intel.com> References: <20180607143807.3611-1-yu-cheng.yu@intel.com> Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Signed-off-by: Yu-cheng Yu --- mm/madvise.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/madvise.c b/mm/madvise.c index 4d3c922ea1a1..2a6988badd6b 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -839,6 +839,14 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) if (vma && start > vma->vm_start) prev = vma; + /* + * Don't do anything on shadow stack. + */ + if (vma->vm_flags & VM_SHSTK) { + error = -EINVAL; + goto out_no_plug; + } + blk_start_plug(&plug); for (;;) { /* Still start < end. */ @@ -876,6 +884,7 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) } out: blk_finish_plug(&plug); +out_no_plug: if (write) up_write(¤t->mm->mmap_sem); else -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html