From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA6C9C282C8 for ; Mon, 28 Jan 2019 17:38:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A5BDA2147A for ; Mon, 28 Jan 2019 17:38:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548697121; bh=/vRaWQKw3q55s8Tz0v2d2naK21I5seaKk7U91gRvlNw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=E49V/EaLJVDCXIy1GUrDs7tvtkcD/jkplvIdIk1f6tJviBq7pJLgKswV9CwI8AM/k Hs4f0NSInC1XYKY98hH/z7eSJntgJO5yVfzcyS1PsBz4A3kuNLJcM8u8C/e8j0D+ec pUhnjD1WAGk6lj4rKFlF+mqB47wIv9WVGGSgf11Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729605AbfA1PyB (ORCPT ); Mon, 28 Jan 2019 10:54:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:40234 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729578AbfA1Px4 (ORCPT ); Mon, 28 Jan 2019 10:53:56 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 29E8E20989; Mon, 28 Jan 2019 15:53:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548690836; bh=/vRaWQKw3q55s8Tz0v2d2naK21I5seaKk7U91gRvlNw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZI7aeIVaE/1+QR/I7E5bxEPbDCpW0Nqary3R+ZFd6X1QvPWAldS/A8KW1l6Pt8c8b CZBeNVccPMJUHsjHwa3flhNd+PF/OgMAPfx73imJJ/omp3NyDRx4wBTAnLBiP0KjKA dtXGcleGSHj8pJZjvDEgLXhfZy5QGhrqLWh98bI0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nicholas Mc Guire , Jiri Kosina , Sasha Levin , live-patching@vger.kernel.org Subject: [PATCH AUTOSEL 4.20 208/304] livepatch: check kzalloc return values Date: Mon, 28 Jan 2019 10:42:05 -0500 Message-Id: <20190128154341.47195-208-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190128154341.47195-1-sashal@kernel.org> References: <20190128154341.47195-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nicholas Mc Guire [ Upstream commit 5f30b2e823484ce6a79f2b59901b6351c15effa6 ] kzalloc() return should always be checked - notably in example code where this may be seen as reference. On failure of allocation in livepatch_fix1_dummy_alloc() respectively dummy_alloc() previous allocation is freed (thanks to Petr Mladek for catching this) and NULL returned. Signed-off-by: Nicholas Mc Guire Fixes: 439e7271dc2b ("livepatch: introduce shadow variable API") Acked-by: Joe Lawrence Reviewed-by: Petr Mladek Acked-by: Miroslav Benes Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- samples/livepatch/livepatch-shadow-fix1.c | 5 +++++ samples/livepatch/livepatch-shadow-mod.c | 4 ++++ 2 files changed, 9 insertions(+) diff --git a/samples/livepatch/livepatch-shadow-fix1.c b/samples/livepatch/livepatch-shadow-fix1.c index 49b13553eaae..e8f1bd6b29b1 100644 --- a/samples/livepatch/livepatch-shadow-fix1.c +++ b/samples/livepatch/livepatch-shadow-fix1.c @@ -89,6 +89,11 @@ struct dummy *livepatch_fix1_dummy_alloc(void) * pointer to handle resource release. */ leak = kzalloc(sizeof(int), GFP_KERNEL); + if (!leak) { + kfree(d); + return NULL; + } + klp_shadow_alloc(d, SV_LEAK, sizeof(leak), GFP_KERNEL, shadow_leak_ctor, leak); diff --git a/samples/livepatch/livepatch-shadow-mod.c b/samples/livepatch/livepatch-shadow-mod.c index 4c54b250332d..4aa8a88d3cd6 100644 --- a/samples/livepatch/livepatch-shadow-mod.c +++ b/samples/livepatch/livepatch-shadow-mod.c @@ -118,6 +118,10 @@ noinline struct dummy *dummy_alloc(void) /* Oops, forgot to save leak! */ leak = kzalloc(sizeof(int), GFP_KERNEL); + if (!leak) { + kfree(d); + return NULL; + } pr_info("%s: dummy @ %p, expires @ %lx\n", __func__, d, d->jiffies_expire); -- 2.19.1