From patchwork Mon Apr 23 12:54:55 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Igor Stoppa X-Patchwork-Id: 10356973 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id F4201601D3 for ; Mon, 23 Apr 2018 12:56:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DBE0E28ABE for ; Mon, 23 Apr 2018 12:56:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D0D8C28AC5; Mon, 23 Apr 2018 12:56:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id DDC0228ABF for ; Mon, 23 Apr 2018 12:56:48 +0000 (UTC) Received: (qmail 23977 invoked by uid 550); 23 Apr 2018 12:56:00 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 23899 invoked from network); 23 Apr 2018 12:55:58 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=jwZ+2itaJiX1jytcWxO0WvnASxd1yHLN4hfAbTqc4CE=; b=lhN+OcL1F2Dgh23zsQVHXiSS7iOC4CipkT3Y4GezELpb9LU3iH0mYtB1QKB/vUHyNh Ww0eyj1bBJvX/ioc4UjXW9tEDeCeySy7XADVfcw8ohIulvB7zYo31Fv2q9JO0uim8kbm +wvIXmn8e7JR0CDthmcHRpV5qDZ8dnaC29tnIbYKebnTpFGTgKclSqqkXWnfE+Qaxol9 B3Sw2z4YiZ1y4ATKbmkFe30h5jq6AzYzjfSiUR+L8WZuRjRUt+77papgUOTCG+xJNaeb QpOx6XkWPiDvD8zH91U4qYA/RFm+Ls3iRC+8gtLWcdoLXSWYdOiW+wqViWaoil7kZnsQ c9zA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=jwZ+2itaJiX1jytcWxO0WvnASxd1yHLN4hfAbTqc4CE=; b=G4f49Ufm8PYXqTdHANMcWVbpSmvHGszty9hXlWnkKHMmUmZOXFQVzTEph2H7O6F8ol 9MHnasxGOldExVXm3Etv5W09w5zaHo19i043DMr+rffWN2Q4sHbPPWPAc1RLebZCgJzM dUM6+qF9l8Kt26yQJPikgnYL88TAJXl6PlBbXerwX8kxOQeK3A0t21G4MIVd02yGeb+P A+kNPULo1NyjrKYoC20LnyxyOWnapHhquGEswhxnFLdpRa0WojaCU6JqBkxn6SFA4L/A ea7fnESW3B2H7kVozzcAzVHTasyoN0xJsefU4QIPwwMWU1K9DDzpWT6MVnHUyUchTsDC BKuw== X-Gm-Message-State: ALQs6tCzWmd5JJIKzQeG+OGo9xuuwHtURUPXA87k0MDBF+2SF2RFzynT NtpIh3jX5WkdBQySocn3DeIbfm/F X-Google-Smtp-Source: AIpwx4+2O5R/ceOPJjqO/bDQnXLhCSL+RLlRV25SgIy+zGqexCfE/SOiRTWjz46mXbWxUhlsC4ka2Q== X-Received: by 2002:a6b:c002:: with SMTP id q2-v6mr20988824iof.53.1524488147155; Mon, 23 Apr 2018 05:55:47 -0700 (PDT) From: Igor Stoppa X-Google-Original-From: Igor Stoppa To: willy@infradead.org, keescook@chromium.org, paul@paul-moore.com, sds@tycho.nsa.gov, mhocko@kernel.org, corbet@lwn.net Cc: labbott@redhat.com, linux-cc=david@fromorbit.com, --cc=rppt@linux.vnet.ibm.com, --security-module@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com, igor.stoppa@gmail.com, Igor Stoppa Subject: [PATCH 6/9] lkdtm: crash on overwriting protected pmalloc var Date: Mon, 23 Apr 2018 16:54:55 +0400 Message-Id: <20180423125458.5338-7-igor.stoppa@huawei.com> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20180423125458.5338-1-igor.stoppa@huawei.com> References: <20180423125458.5338-1-igor.stoppa@huawei.com> X-Virus-Scanned: ClamAV using ClamSMTP Verify that pmalloc read-only protection is in place: trying to overwrite a protected variable will crash the kernel. Signed-off-by: Igor Stoppa --- drivers/misc/lkdtm/core.c | 3 +++ drivers/misc/lkdtm/lkdtm.h | 1 + drivers/misc/lkdtm/perms.c | 25 +++++++++++++++++++++++++ 3 files changed, 29 insertions(+) diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c index 2154d1bfd18b..c9fd42bda6ee 100644 --- a/drivers/misc/lkdtm/core.c +++ b/drivers/misc/lkdtm/core.c @@ -155,6 +155,9 @@ static const struct crashtype crashtypes[] = { CRASHTYPE(ACCESS_USERSPACE), CRASHTYPE(WRITE_RO), CRASHTYPE(WRITE_RO_AFTER_INIT), +#ifdef CONFIG_PROTECTABLE_MEMORY + CRASHTYPE(WRITE_RO_PMALLOC), +#endif CRASHTYPE(WRITE_KERN), CRASHTYPE(REFCOUNT_INC_OVERFLOW), CRASHTYPE(REFCOUNT_ADD_OVERFLOW), diff --git a/drivers/misc/lkdtm/lkdtm.h b/drivers/misc/lkdtm/lkdtm.h index 9e513dcfd809..dcda3ae76ceb 100644 --- a/drivers/misc/lkdtm/lkdtm.h +++ b/drivers/misc/lkdtm/lkdtm.h @@ -38,6 +38,7 @@ void lkdtm_READ_BUDDY_AFTER_FREE(void); void __init lkdtm_perms_init(void); void lkdtm_WRITE_RO(void); void lkdtm_WRITE_RO_AFTER_INIT(void); +void lkdtm_WRITE_RO_PMALLOC(void); void lkdtm_WRITE_KERN(void); void lkdtm_EXEC_DATA(void); void lkdtm_EXEC_STACK(void); diff --git a/drivers/misc/lkdtm/perms.c b/drivers/misc/lkdtm/perms.c index 53b85c9d16b8..3c81e59f9d9d 100644 --- a/drivers/misc/lkdtm/perms.c +++ b/drivers/misc/lkdtm/perms.c @@ -9,6 +9,7 @@ #include #include #include +#include #include /* Whether or not to fill the target memory area with do_nothing(). */ @@ -104,6 +105,30 @@ void lkdtm_WRITE_RO_AFTER_INIT(void) *ptr ^= 0xabcd1234; } +#ifdef CONFIG_PROTECTABLE_MEMORY +void lkdtm_WRITE_RO_PMALLOC(void) +{ + struct pmalloc_pool *pool; + int *i; + + pool = pmalloc_create_pool(); + if (WARN(!pool, "Failed preparing pool for pmalloc test.")) + return; + + i = pmalloc(pool, sizeof(int)); + if (WARN(!i, "Failed allocating memory for pmalloc test.")) { + pmalloc_destroy_pool(pool); + return; + } + + *i = INT_MAX; + pmalloc_protect_pool(pool); + + pr_info("attempting bad pmalloc write at %p\n", i); + *i = 0; +} +#endif + void lkdtm_WRITE_KERN(void) { size_t size;