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 C66C3C433F5 for ; Mon, 4 Apr 2022 15:07:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378433AbiDDPJ2 (ORCPT ); Mon, 4 Apr 2022 11:09:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378221AbiDDPJZ (ORCPT ); Mon, 4 Apr 2022 11:09:25 -0400 Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99F3F38BE7 for ; Mon, 4 Apr 2022 08:07:28 -0700 (PDT) Received: by mail-lf1-x12d.google.com with SMTP id p10so17812501lfa.12 for ; Mon, 04 Apr 2022 08:07:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=l4K0SPmrnpSn+fuUk7g4we7BJ74/J43n2XWdTPtmJBY=; b=Ad07ZzvunE3vZQtLzo5oDTRUrzKUmJcuBL0FbcbaEl0KGYWarSn0QKuZZQYbwuSSuZ wtcBtSCHTQCgVtySsb2f4cNXXgfmVXK9iMYOf7MZ8y2nj2EgEjxwxeNHht4iVplfXfs/ nUa+TtF0GebuFRkL+TKr16ROoQMr5Yz3by+75gob+fzrIq9suL3OQa6U983SQWsxerHL bVKih6bEwFv0tyn/gswydnIFA9qXCvebjlDigAgglaUW4OGpSYAjXGPZrj5u3ErtP7AF P7gtJ6ROBlM1en4GGhJ2seEKlMov16qqLwWSW0E22p+H8rehyhyy8EXaywJ9Xd5E5+i5 CZSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=l4K0SPmrnpSn+fuUk7g4we7BJ74/J43n2XWdTPtmJBY=; b=I6XUGr5xX0CJpNYCDrnQxRE2T0mjAXqmEtVm7tD+MJY5wjcq/QaT8rdWIJumGs4WCH qmKuerdpKoYog4pDW7yc5gXYtHs7MZL+2YdG3zs3D8sjy/ZjytXAA43T6fOWb2c9K273 jdLmoxK+WSpBaq0sOx+vmQJHpPAl7yELBydDD3Y48RFcxuW4Zl3o4bM6ibhrmIhmk4e3 OTfYldZzpOpD3C7lvcxnc9fRwzcgO1DBT+tNVlOX6t3qtvCOBhFJK2CoqCA31Earho1z 1DcFWiBKNtGaWIR7w2Lh8bl51gixt674JZsu7s4Oi4Rjm/IaF1i9We4fr8h2VQIxqXNT D3tw== X-Gm-Message-State: AOAM530eT6KVK+LZT37OOuM27hEn/gfRk6zIFLMLdVzaiHccnXxwj48i fl5rMaNSFWOZngK5Mr6xohE= X-Google-Smtp-Source: ABdhPJwRKTX9sNlZWMzdB6xUQCUTu18lQdxp4IePtSAY9nUucUvvosWFtS7ZPo9Md4LR3rZGocfQTg== X-Received: by 2002:a05:6512:280d:b0:44f:5af8:1958 with SMTP id cf13-20020a056512280d00b0044f5af81958mr76653lfb.533.1649084846725; Mon, 04 Apr 2022 08:07:26 -0700 (PDT) Received: from freyja.wlan (dzx1kfyjwg96s--vr8cxy-3.rev.dnainternet.fi. [2001:14ba:a4ea:8200:f22f:74ff:fe2e:e0a6]) by smtp.gmail.com with ESMTPSA id bi2-20020a0565120e8200b0044826a117bcsm1163279lfb.44.2022.04.04.08.07.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 Apr 2022 08:07:26 -0700 (PDT) From: Jan Varho To: "Jason A. Donenfeld" , "Theodore Ts'o" Cc: linux-kernel@vger.kernel.org, Jan Varho Subject: [PATCH] random: fix add_hwgenerator_randomness entropy accounting Date: Mon, 4 Apr 2022 18:04:42 +0300 Message-Id: <20220404150442.934496-1-jan.varho@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org add_hwgenerator_randomness tries to only use the required amound of input for fast init, but credits all the entropy if even a byte was left over. Fix by not crediting entropy if any input was consumed for fast init. Signed-off-by: Jan Varho --- drivers/char/random.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 1d8242969751..fb20178f1044 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1141,12 +1141,10 @@ void add_hwgenerator_randomness(const void *buffer, size_t count, size_t entropy) { if (unlikely(crng_init == 0 && entropy < POOL_MIN_BITS)) { - size_t ret = crng_pre_init_inject(buffer, count, true); - mix_pool_bytes(buffer, ret); - count -= ret; - buffer += ret; - if (!count || crng_init == 0) + if (crng_pre_init_inject(buffer, count, true) > 0) { + mix_pool_bytes(buffer, count); return; + } } /* -- 2.25.1