From patchwork Wed May 12 14:46:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 436717 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04202C2B9F7 for ; Wed, 12 May 2021 16:12:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA56C61D4B for ; Wed, 12 May 2021 16:12:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237802AbhELQNY (ORCPT ); Wed, 12 May 2021 12:13:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:33626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239282AbhELQHm (ORCPT ); Wed, 12 May 2021 12:07:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A129761C59; Wed, 12 May 2021 15:37:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620833830; bh=Uxz7oMteSxfFHU48bBX/AmUX+Xv2sHNP8sQl4iLm4c0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iJVfUGpYomt7T0Vx099b156X35IGuiVZ5paTP2DURE+v1rlcUDxjkjV4NLj7y/865 UBTPf9I/LwZP3W4L7L+VYd81Qx4OeplzPEC+8lO1eMDSwSaFT/5bJ+pEkSzkQOzpdm yq/oxRA6qjiZofs0C1n9AQc2Yl1BRbVREQEplVxk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Joel Stanley , Patrick Venture , Arnd Bergmann , Sasha Levin Subject: [PATCH 5.11 306/601] soc: aspeed: fix a ternary sign expansion bug Date: Wed, 12 May 2021 16:46:23 +0200 Message-Id: <20210512144837.896496347@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144827.811958675@linuxfoundation.org> References: <20210512144827.811958675@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dan Carpenter [ Upstream commit 5ffa828534036348fa90fb3079ccc0972d202c4a ] The intent here was to return negative error codes but it actually returns positive values. The problem is that type promotion with ternary operations is quite complicated. "ret" is an int. "copied" is a u32. And the snoop_file_read() function returns long. What happens is that "ret" is cast to u32 and becomes positive then it's cast to long and it's still positive. Fix this by removing the ternary so that "ret" is type promoted directly to long. Fixes: 3772e5da4454 ("drivers/misc: Aspeed LPC snoop output using misc chardev") Signed-off-by: Dan Carpenter Signed-off-by: Joel Stanley Reviewed-by: Patrick Venture Link: https://lore.kernel.org/r/YIE90PSXsMTa2Y8n@mwanda Link: https://lore.kernel.org/r/20210423000919.1249474-1-joel@jms.id.au' Signed-off-by: Arnd Bergmann Signed-off-by: Sasha Levin --- drivers/soc/aspeed/aspeed-lpc-snoop.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/aspeed-lpc-snoop.c index 20acac6342ef..5828f94b8a7d 100644 --- a/drivers/soc/aspeed/aspeed-lpc-snoop.c +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c @@ -95,8 +95,10 @@ static ssize_t snoop_file_read(struct file *file, char __user *buffer, return -EINTR; } ret = kfifo_to_user(&chan->fifo, buffer, count, &copied); + if (ret) + return ret; - return ret ? ret : copied; + return copied; } static __poll_t snoop_file_poll(struct file *file,