From nobody Fri Dec 19 04:23:33 2025 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 45E99C38A2D for ; Mon, 24 Oct 2022 22:49:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230337AbiJXWt3 (ORCPT ); Mon, 24 Oct 2022 18:49:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40312 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231490AbiJXWsl (ORCPT ); Mon, 24 Oct 2022 18:48:41 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EEC52CF4A7; Mon, 24 Oct 2022 14:10:51 -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 sin.source.kernel.org (Postfix) with ESMTPS id 61AD7CE1318; Mon, 24 Oct 2022 11:39:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 54791C433C1; Mon, 24 Oct 2022 11:39:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666611574; bh=7d0m2Z6BIjDkYt6daIwwF++izl41uVIUnp2ibyflk6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PQOl9iOX1nyMMdTkqlnUOGy+zJo4rwFZrxjLlMSfp2LoYeAZ45xncW5QYJMIocoGV fuxc9X6yt0vC4cWJFirkCcwj/aLDv6/8xlck+d2zl5JxydpwRuvTf+A/cOO0vclN4s hfkyiQi9DLFe2/SwEufbbfoCBE0AraVp5skKVth8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Jason A. Donenfeld" Subject: [PATCH 4.9 031/159] random: clamp credited irq bits to maximum mixed Date: Mon, 24 Oct 2022 13:29:45 +0200 Message-Id: <20221024112950.545644221@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112949.358278806@linuxfoundation.org> References: <20221024112949.358278806@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Jason A. Donenfeld commit e78a802a7b4febf53f2a92842f494b01062d85a8 upstream. Since the most that's mixed into the pool is sizeof(long)*2, don't credit more than that many bytes of entropy. Fixes: e3e33fc2ea7f ("random: do not use input pool from hard IRQs") Cc: stable@vger.kernel.org Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman --- drivers/char/random.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -977,7 +977,7 @@ static void mix_interrupt_randomness(str local_irq_enable(); =20 mix_pool_bytes(pool, sizeof(pool)); - credit_init_bits(max(1u, (count & U16_MAX) / 64)); + credit_init_bits(clamp_t(unsigned int, (count & U16_MAX) / 64, 1, sizeof(= pool) * 8)); =20 memzero_explicit(pool, sizeof(pool)); }