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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 747D8C04E87 for ; Mon, 20 May 2019 12:45:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4046120645 for ; Mon, 20 May 2019 12:45:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558356336; bh=8wo6OfwoxBhKFRN2XsFLYEb1OgS1BAfDkVDQKopJ80A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=HaGcgT5hZhE2aqLkLGeVzI5gCFgPBvEZRgsUPX3i9glcv5aE78vB21u48FNvWf2sT 9naFS+ZAagKlbS4cdomW4g6LN29IeqxgpkLFWMLyFcX6McSxdpQMC188ZLFYmkqo9r l2jVxagkf2vV2Ga4fLHiYSDDC3tWbnUPmLcn0UFc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388942AbfETM0k (ORCPT ); Mon, 20 May 2019 08:26:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:42022 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388017AbfETM0h (ORCPT ); Mon, 20 May 2019 08:26:37 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 254C121479; Mon, 20 May 2019 12:26:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558355196; bh=8wo6OfwoxBhKFRN2XsFLYEb1OgS1BAfDkVDQKopJ80A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j6YY194Q9axogROGSaVpEvkdMOR3WDtbhpN91u1iI+4y9uc5dZZ2YDQF11fFu2NVM pOzP/IN/UOwZSDNTkM/ZK1emdYKD3+s88GSv6R4SycTUJX2FfC2ciOBaK0i5j7HsaD PVdXh9MCgUkRxc/RofTe9JGjFAITI5LmfcW6IKsg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ondrej Mosnacek , Eric Biggers , Herbert Xu Subject: [PATCH 5.0 028/123] crypto: lrw - dont access already-freed walk.iv Date: Mon, 20 May 2019 14:13:28 +0200 Message-Id: <20190520115246.657720313@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190520115245.439864225@linuxfoundation.org> References: <20190520115245.439864225@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Biggers commit aec286cd36eacfd797e3d5dab8d5d23c15d1bb5e upstream. If the user-provided IV needs to be aligned to the algorithm's alignmask, then skcipher_walk_virt() copies the IV into a new aligned buffer walk.iv. But skcipher_walk_virt() can fail afterwards, and then if the caller unconditionally accesses walk.iv, it's a use-after-free. Fix this in the LRW template by checking the return value of skcipher_walk_virt(). This bug was detected by my patches that improve testmgr to fuzz algorithms against their generic implementation. When the extra self-tests were run on a KASAN-enabled kernel, a KASAN use-after-free splat occured during lrw(aes) testing. Fixes: c778f96bf347 ("crypto: lrw - Optimize tweak computation") Cc: # v4.20+ Cc: Ondrej Mosnacek Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/lrw.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/crypto/lrw.c +++ b/crypto/lrw.c @@ -162,8 +162,10 @@ static int xor_tweak(struct skcipher_req } err = skcipher_walk_virt(&w, req, false); - iv = (__be32 *)w.iv; + if (err) + return err; + iv = (__be32 *)w.iv; counter[0] = be32_to_cpu(iv[3]); counter[1] = be32_to_cpu(iv[2]); counter[2] = be32_to_cpu(iv[1]);