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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D5F0C433EF for ; Mon, 18 Apr 2022 13:22:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241339AbiDRNYq (ORCPT ); Mon, 18 Apr 2022 09:24:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241822AbiDRNDa (ORCPT ); Mon, 18 Apr 2022 09:03:30 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9515333EA7; Mon, 18 Apr 2022 05:44:36 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 294966124B; Mon, 18 Apr 2022 12:44:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B743C385A1; Mon, 18 Apr 2022 12:44:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1650285875; bh=qnqwhrdpHXehWZti7jwWW0CXMprTUZWAfoCcm83XbaA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WoW3qAIfljgVWwhwvXcmGfg2U5fxUPbJ1CGbcM08HQAOYVA07ItW8DQhT1xkzu1SC NHdIpJ5ePWa0XVTe6Q7moEKiQMDPCHkrfflNnLOoVh4VXE+OS5D5i8W1kgZ12g4Rhw f8jmXy53jp9Hw4x/228IIU9i0reXtfQWldrV0lUM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Mike Snitzer Subject: [PATCH 5.4 52/63] dm integrity: fix memory corruption when tag_size is less than digest size Date: Mon, 18 Apr 2022 14:13:49 +0200 Message-Id: <20220418121137.673942608@linuxfoundation.org> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20220418121134.149115109@linuxfoundation.org> References: <20220418121134.149115109@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikulas Patocka commit 08c1af8f1c13bbf210f1760132f4df24d0ed46d6 upstream. It is possible to set up dm-integrity in such a way that the "tag_size" parameter is less than the actual digest size. In this situation, a part of the digest beyond tag_size is ignored. In this case, dm-integrity would write beyond the end of the ic->recalc_tags array and corrupt memory. The corruption happened in integrity_recalc->integrity_sector_checksum->crypto_shash_final. Fix this corruption by increasing the tags array so that it has enough padding at the end to accomodate the loop in integrity_recalc() being able to write a full digest size for the last member of the tags array. Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-integrity.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -4054,6 +4054,7 @@ try_smaller_buffer: } if (ic->internal_hash) { + size_t recalc_tags_size; ic->recalc_wq = alloc_workqueue("dm-integrity-recalc", WQ_MEM_RECLAIM, 1); if (!ic->recalc_wq ) { ti->error = "Cannot allocate workqueue"; @@ -4067,8 +4068,10 @@ try_smaller_buffer: r = -ENOMEM; goto bad; } - ic->recalc_tags = kvmalloc_array(RECALC_SECTORS >> ic->sb->log2_sectors_per_block, - ic->tag_size, GFP_KERNEL); + recalc_tags_size = (RECALC_SECTORS >> ic->sb->log2_sectors_per_block) * ic->tag_size; + if (crypto_shash_digestsize(ic->internal_hash) > ic->tag_size) + recalc_tags_size += crypto_shash_digestsize(ic->internal_hash) - ic->tag_size; + ic->recalc_tags = kvmalloc(recalc_tags_size, GFP_KERNEL); if (!ic->recalc_tags) { ti->error = "Cannot allocate tags for recalculating"; r = -ENOMEM;