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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 B90F3C282CE for ; Mon, 11 Feb 2019 16:02:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 836C9218D8 for ; Mon, 11 Feb 2019 16:02:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549900950; bh=yIvTbwd3Xq8HveIJYZX05QBb+Dn6UDUr6nK6r5UEa8Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ouYQlVjkKCSb8+48Oy+KOmau0ifbu7IoPeiE0ZyAy/Bh0hGhdwWEqfHRwRuohquFs ofk8uhejd/q9DJYCnljbSeq0NvsWJzo3iIH4QplKIrHoyUS9XmTJBzVDxvatS682dX vlgCWoUjNWTibZGiPYxC4KvBca+dpCS5sKyMYR48= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730830AbfBKQC3 (ORCPT ); Mon, 11 Feb 2019 11:02:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:36624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729606AbfBKOaP (ORCPT ); Mon, 11 Feb 2019 09:30:15 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9063720675; Mon, 11 Feb 2019 14:30:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895415; bh=yIvTbwd3Xq8HveIJYZX05QBb+Dn6UDUr6nK6r5UEa8Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f6gT0XXY5kn3ouB5o/fYi4fDjoYUhZHhIQnWzdm27zi8yIWFilAOh5EOhbXzwL5Bn KIkXEYdE4dtWBo9+2/H3qHWNm6LoiVI4J1dJY5jqQjN+6jkuujZpuDt7uj5SfWKMbd zHviTK51O9+s2aYFVSLZqx/8xlUDV1dkpbUX+pqc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Mc Guire , Joe Lawrence , Petr Mladek , Miroslav Benes , Jiri Kosina , Sasha Levin Subject: [PATCH 4.20 197/352] livepatch: check kzalloc return values Date: Mon, 11 Feb 2019 15:17:04 +0100 Message-Id: <20190211141859.673024218@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141846.543045703@linuxfoundation.org> References: <20190211141846.543045703@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ 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