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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 6AD68C2B9F6 for ; Mon, 10 May 2021 11:41:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 38C9E613EE for ; Mon, 10 May 2021 11:41:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240761AbhEJLgf (ORCPT ); Mon, 10 May 2021 07:36:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:41914 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231167AbhEJKwX (ORCPT ); Mon, 10 May 2021 06:52:23 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8C03461A33; Mon, 10 May 2021 10:41:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620643271; bh=syKh//1zBxW2bsse+MyJ23bGnmI1eRoX+g3ccSSI15E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aUPy/bzBoSQ8Kr4glNUXakkYeF2fO5Ne/uhF93zWkDD+k5Q8hJFtJYOwfYmliR1f5 giXISy3RfPKhQtUbsU5G1DWecwnUcOD2Xaf63sVOqAwgPx5TAraZRwtJFHUR/7KcrH +08N1X7Bb2Y6KNgFvAbz/qVgZbzclhnkMv050hAY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , Herbert Xu Subject: [PATCH 5.10 248/299] crypto: rng - fix crypto_rng_reset() refcounting when !CRYPTO_STATS Date: Mon, 10 May 2021 12:20:45 +0200 Message-Id: <20210510102013.149821787@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102004.821838356@linuxfoundation.org> References: <20210510102004.821838356@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: Eric Biggers commit 30d0f6a956fc74bb2e948398daf3278c6b08c7e9 upstream. crypto_stats_get() is a no-op when the kernel is compiled without CONFIG_CRYPTO_STATS, so pairing it with crypto_alg_put() unconditionally (as crypto_rng_reset() does) is wrong. Fix this by moving the call to crypto_stats_get() to just before the actual algorithm operation which might need it. This makes it always paired with crypto_stats_rng_seed(). Fixes: eed74b3eba9e ("crypto: rng - Fix a refcounting bug in crypto_rng_reset()") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/rng.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) --- a/crypto/rng.c +++ b/crypto/rng.c @@ -34,22 +34,18 @@ int crypto_rng_reset(struct crypto_rng * u8 *buf = NULL; int err; - crypto_stats_get(alg); if (!seed && slen) { buf = kmalloc(slen, GFP_KERNEL); - if (!buf) { - crypto_alg_put(alg); + if (!buf) return -ENOMEM; - } err = get_random_bytes_wait(buf, slen); - if (err) { - crypto_alg_put(alg); + if (err) goto out; - } seed = buf; } + crypto_stats_get(alg); err = crypto_rng_alg(tfm)->seed(tfm, seed, slen); crypto_stats_rng_seed(alg, err); out: