From patchwork Tue Jun 6 00:50:59 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 9767787 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 3ED786034B for ; Tue, 6 Jun 2017 00:53:52 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 33FF427968 for ; Tue, 6 Jun 2017 00:53:52 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 28C0228435; Tue, 6 Jun 2017 00:53:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B614D27968 for ; Tue, 6 Jun 2017 00:53:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751369AbdFFAvj (ORCPT ); Mon, 5 Jun 2017 20:51:39 -0400 Received: from frisell.zx2c4.com ([192.95.5.64]:57707 "EHLO frisell.zx2c4.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751194AbdFFAvh (ORCPT ); Mon, 5 Jun 2017 20:51:37 -0400 Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTP id bd03bb62; Tue, 6 Jun 2017 00:51:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=zx2c4.com; h=from:to:cc :subject:date:message-id:in-reply-to:references; s=mail; bh=+iG8 fh1akOdU0hy7JPc3a3o9Lqs=; b=C88X9Ses5MoAhEvexGfzeEECYfA+HzmBqt7m zh7T7k0RkPsy9kReChkuiMkgAXBaljPEXutxkeSsqMm0Z8x3COMSA1JCYmXajKCz bh9ZBQId/rejhuZ6VMul8Z/y6+s24XNlRtAVHMuZCa3WMikAk27vJ2kG0xmngrIE sKOg1jEY29hk7FC1dnNQrqLMZLhLSFmC998VQns9FDe+ylRFVG/1qxcPzl5BsPTa TuvA2f0HCXd5XvqWxVTex4kIullTQgzMIWZ4oNsKkrvkVSSx2KkGokABDWrYTAq8 lwo1nLbV7goXSJuTiQ8Hi8t4vZopcH/MalnNVYXwYTaGxuN67Q== Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 8cf05835 (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Tue, 6 Jun 2017 00:51:20 +0000 (UTC) From: "Jason A. Donenfeld" To: Theodore Ts'o , Linux Crypto Mailing List , LKML , kernel-hardening@lists.openwall.com, Greg Kroah-Hartman , David Miller Cc: "Jason A. Donenfeld" , Herbert Xu Subject: [PATCH v3 04/13] crypto/rng: ensure that the RNG is ready before using Date: Tue, 6 Jun 2017 02:50:59 +0200 Message-Id: <20170606005108.5646-5-Jason@zx2c4.com> X-Mailer: git-send-email 2.13.0 In-Reply-To: <20170606005108.5646-1-Jason@zx2c4.com> References: <20170606005108.5646-1-Jason@zx2c4.com> Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Otherwise, we might be seeding the RNG using bad randomness, which is dangerous. Cc: Herbert Xu Signed-off-by: Jason A. Donenfeld --- crypto/rng.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/crypto/rng.c b/crypto/rng.c index f46dac5288b9..e042437e64b4 100644 --- a/crypto/rng.c +++ b/crypto/rng.c @@ -48,12 +48,14 @@ int crypto_rng_reset(struct crypto_rng *tfm, const u8 *seed, unsigned int slen) if (!buf) return -ENOMEM; - get_random_bytes(buf, slen); + err = get_random_bytes_wait(buf, slen); + if (err) + goto out; seed = buf; } err = crypto_rng_alg(tfm)->seed(tfm, seed, slen); - +out: kzfree(buf); return err; }