From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx48stXTcUa+Q0vZVP1KpEfykNgIJg1HwRTyMpWTvy3z7bguU7uL1WKScWAqDzodnhWNAw29C ARC-Seal: i=1; a=rsa-sha256; t=1524488215; cv=none; d=google.com; s=arc-20160816; b=yvEP7IcV09dL4dQhMbpVmZF8jeM6X722LnLl1x2KEDIR8BTZdbnpsFFtNJn4y+vhiz qKYX52+afdTs6q2slFw0bOFe9jspbO5Ert4+29av0yDpu1wtC0ytFu6ogc0zRXzHXitv 7dEFuml1oj1/5k/51yo1wAPJVG7qnIxqItxiMXJ0IA9F7HkMiLBmhjfiNcnkpxx6zGnX eJ96ftX7frJY0OKTgQZ3sHLCKnI6ZLN4FdzYsTl1r/aRVxxCPHbb//GgCuzsHgD355RX WL4ed2YehPjexbAU2c2MQsnuOTDBOG8yhyCRosvzojFAyd13AtmeU4fCHYLNxE43X7Vz ZRZw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:delivered-to:list-id:list-subscribe:list-unsubscribe :list-help:list-post:precedence:mailing-list :arc-authentication-results; bh=jwZ+2itaJiX1jytcWxO0WvnASxd1yHLN4hfAbTqc4CE=; b=cezQ2VVtK6eGIjrgfY6H/PxMdhLhapUs+QK904D29r8zD3YoIbfHZAtOzEC+V2TazY RqZxNFeJzBbgwbA6LYhdvR5UFl+B7lj+EQMIm7ipbfYlBiIepa7Jf7QMGxH76cFjDZEu 3/H1bHZcfx+s6BC8k9R9TV8ML6osSphAbij/X2JE4wYDI3zMlCSLMKBKB+TZRDcoGzuo EREoplWiz4inc9ULg5aavmeXIyzBDzSDJA7qdwqHnZPA+qtYt/URBrlbGik0otkxmIxL O4b5skVJsXosv8Gb+ggFWy/AB8buv+POJ4If2qUo81nOyrlFIVr1AACnHKjkd2hgvcuS NKWA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=lhN+OcL1; spf=pass (google.com: domain of kernel-hardening-return-13094-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-13094-gregkh=linuxfoundation.org@lists.openwall.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=lhN+OcL1; spf=pass (google.com: domain of kernel-hardening-return-13094-gregkh=linuxfoundation.org@lists.openwall.com designates 195.42.179.200 as permitted sender) smtp.mailfrom=kernel-hardening-return-13094-gregkh=linuxfoundation.org@lists.openwall.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm List-Post: List-Help: List-Unsubscribe: List-Subscribe: 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-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1598541754692196067?= X-GMAIL-MSGID: =?utf-8?q?1598541754692196067?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 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; -- 2.14.1