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 E294EECAAA1 for ; Mon, 24 Oct 2022 12:23:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233341AbiJXMW6 (ORCPT ); Mon, 24 Oct 2022 08:22:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233339AbiJXMUx (ORCPT ); Mon, 24 Oct 2022 08:20:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2250C7B5AF; Mon, 24 Oct 2022 04:59:08 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 44567612F4; Mon, 24 Oct 2022 11:56:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57A0DC433C1; Mon, 24 Oct 2022 11:56:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666612611; bh=Sf4p/I5+I0rasfxMUpNRv3gda7JlSUROFiBRNveWqCk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lL7JG+AadCkavVvKX5AoANZP4mRPuBxUOaE/3UUoV46dwNGfVkZQeZLfgQaipgxhQ owgQPHBx5qLocySI/ug5q/nPBqhJrpg+9bhpCCPJZv6dL+P00zCvlLLBwhC3opuV1t nze3fg1tjoXm5QgwNvcjxUa4iX9IoEwf8tMeeCkI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Jason A. Donenfeld" Subject: [PATCH 4.19 022/229] random: clamp credited irq bits to maximum mixed Date: Mon, 24 Oct 2022 13:29:01 +0200 Message-Id: <20221024112959.856505864@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112959.085534368@linuxfoundation.org> References: <20221024112959.085534368@linuxfoundation.org> User-Agent: quilt/0.67 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: 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 @@ -976,7 +976,7 @@ static void mix_interrupt_randomness(str local_irq_enable(); 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)); memzero_explicit(pool, sizeof(pool)); }