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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 92D87C606BD for ; Mon, 8 Jul 2019 15:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B05320665 for ; Mon, 8 Jul 2019 15:39:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562600380; bh=XQyksg6BQprAUNPQBRwXdMzPOwjy+Jls0OH6AIq2J9M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=L5ClzFeweF/jJWj3JkG4lN7vdmNY1IYA75HS8lN+dW0OCgxo2qhKcOOdgXzbrzXHW ZeOiVA10VgIlFhGwjtP9e1AkxqRVXdn3+ffy/Pm9BWzjOSN73kYL0WWL0X7OujXSBN X17Qa0kzmcHTSXvXVNmugThgfOB/CSiE1wwZRwAA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389458AbfGHP3V (ORCPT ); Mon, 8 Jul 2019 11:29:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:58132 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725840AbfGHP3V (ORCPT ); Mon, 8 Jul 2019 11:29:21 -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 CFC8821537; Mon, 8 Jul 2019 15:29:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562599760; bh=XQyksg6BQprAUNPQBRwXdMzPOwjy+Jls0OH6AIq2J9M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pDjlcSIlSYkXNURtwjQBjupaufezEQD8XIJVMY1/qH94r8TW6vavaOnxO9ngDHvWj JYlhZn+Mb4w/nWYTjd8kkaQ8rGCuMADDTNAfOnlTixoFh678uxyvNhV423Ru3ao9AT JjhzaGwVCInS5zgOAeKkNlHn+4qaNoatIMs8lKy8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michal Suchanek , Steffen Klassert , Eric Biggers , Herbert Xu Subject: [PATCH 4.19 42/90] crypto: user - prevent operating on larval algorithms Date: Mon, 8 Jul 2019 17:13:09 +0200 Message-Id: <20190708150524.687220407@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190708150521.829733162@linuxfoundation.org> References: <20190708150521.829733162@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 21d4120ec6f5b5992b01b96ac484701163917b63 upstream. Michal Suchanek reported [1] that running the pcrypt_aead01 test from LTP [2] in a loop and holding Ctrl-C causes a NULL dereference of alg->cra_users.next in crypto_remove_spawns(), via crypto_del_alg(). The test repeatedly uses CRYPTO_MSG_NEWALG and CRYPTO_MSG_DELALG. The crash occurs when the instance that CRYPTO_MSG_DELALG is trying to unregister isn't a real registered algorithm, but rather is a "test larval", which is a special "algorithm" added to the algorithms list while the real algorithm is still being tested. Larvals don't have initialized cra_users, so that causes the crash. Normally pcrypt_aead01 doesn't trigger this because CRYPTO_MSG_NEWALG waits for the algorithm to be tested; however, CRYPTO_MSG_NEWALG returns early when interrupted. Everything else in the "crypto user configuration" API has this same bug too, i.e. it inappropriately allows operating on larval algorithms (though it doesn't look like the other cases can cause a crash). Fix this by making crypto_alg_match() exclude larval algorithms. [1] https://lkml.kernel.org/r/20190625071624.27039-1-msuchanek@suse.de [2] https://github.com/linux-test-project/ltp/blob/20190517/testcases/kernel/crypto/pcrypt_aead01.c Reported-by: Michal Suchanek Fixes: a38f7907b926 ("crypto: Add userspace configuration API") Cc: # v3.2+ Cc: Steffen Klassert Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/crypto_user.c | 3 +++ 1 file changed, 3 insertions(+) --- a/crypto/crypto_user.c +++ b/crypto/crypto_user.c @@ -55,6 +55,9 @@ static struct crypto_alg *crypto_alg_mat list_for_each_entry(q, &crypto_alg_list, cra_list) { int match = 0; + if (crypto_is_larval(q)) + continue; + if ((q->cra_flags ^ p->cru_type) & p->cru_mask) continue;