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 5BAECC4332F for ; Thu, 13 Oct 2022 18:02:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230423AbiJMSCr (ORCPT ); Thu, 13 Oct 2022 14:02:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230453AbiJMSC3 (ORCPT ); Thu, 13 Oct 2022 14:02:29 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 780C611465; Thu, 13 Oct 2022 11:02:26 -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 ams.source.kernel.org (Postfix) with ESMTPS id 98879B82050; Thu, 13 Oct 2022 17:58:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9A31C433D6; Thu, 13 Oct 2022 17:58:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1665683919; bh=SzjUWlrxdx6dSBn+CgiQOoaJon3rIv0huAMKubMWhmc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LS2mzlz/b5Kdya9N8IqyEurfMDytA4edDfDeSbIDYL3REvu4ea7HDWrPj8vFLd6Sn TdOXRbLBTAF1LUTA/HjeeiuBSMt2+4of6iUHoPJRV6dIZVdMLa2FfYkkd7p2JzbDMS bsC1whr5v7gOQELPhVJfCWdhmlmAMs0XB2H/xyfk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Jason A. Donenfeld" Subject: [PATCH 5.15 07/27] random: clamp credited irq bits to maximum mixed Date: Thu, 13 Oct 2022 19:52:36 +0200 Message-Id: <20221013175143.791866092@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221013175143.518476113@linuxfoundation.org> References: <20221013175143.518476113@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: stable@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 @@ -980,7 +980,7 @@ 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)); }