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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 166CAC76186 for ; Mon, 29 Jul 2019 20:15:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D57E32070B for ; Mon, 29 Jul 2019 20:15:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564431354; bh=Tu2SmrOsQqUe9ACAyBEFF/lSAeSN+5gPhxezGHmRkwY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cJjnYJlxWnbmHxESeJi0gvHnQLlHRNe3p/hW3YE2fPBH5wLaLAYRjpr4jZK+mRoZ3 xWuueYU9WV+LLDs3lyo3Epk/0JK9P3TaYOAlMTSrE0UgTGAx/2zlxCg7on4nKTFK8k 0WLBTFbYoQNX5bqtKWchPkSBMIwU4Eq9z0+F8P/M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388284AbfG2TZW (ORCPT ); Mon, 29 Jul 2019 15:25:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:37636 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388281AbfG2TZV (ORCPT ); Mon, 29 Jul 2019 15:25:21 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0B1B920C01; Mon, 29 Jul 2019 19:25:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564428320; bh=Tu2SmrOsQqUe9ACAyBEFF/lSAeSN+5gPhxezGHmRkwY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AlyfkWeStX+XCQuHAenWfRWAXcKIc9lltneRO5Ai8XGaWSD6byFIfarKqGGmYXkwH P9wWTJ5n0gJwYqSp5mXpc7pc7cU4LhXXjfn4/44kwXxzxGpcNHw7BLQU8cpETtciV6 ufpiesH9HBj9PT8Whi/4zAngSG7chTganyeYIbUM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Borislav Petkov , Tony Luck , linux-edac , Sasha Levin Subject: [PATCH 4.14 038/293] RAS/CEC: Fix pfn insertion Date: Mon, 29 Jul 2019 21:18:49 +0200 Message-Id: <20190729190825.269610232@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190729190820.321094988@linuxfoundation.org> References: <20190729190820.321094988@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org [ Upstream commit 6d8e294bf5f0e85c34e8b14b064e2965f53f38b0 ] When inserting random PFNs for debugging the CEC through (debugfs)/ras/cec/pfn, depending on the return value of pfn_set(), multiple values get inserted per a single write. That is because simple_attr_write() interprets a retval of 0 as success and claims the whole input. However, pfn_set() returns the cec_add_elem() value, which, if > 0 and smaller than the whole input length, makes glibc continue issuing the write syscall until there's input left: pfn_set simple_attr_write debugfs_attr_write full_proxy_write vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe leading to those repeated calls. Return 0 to fix that. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac Signed-off-by: Sasha Levin --- drivers/ras/cec.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/ras/cec.c b/drivers/ras/cec.c index c7205cdcc11a..97cf40a522be 100644 --- a/drivers/ras/cec.c +++ b/drivers/ras/cec.c @@ -373,7 +373,9 @@ static int pfn_set(void *data, u64 val) { *(u64 *)data = val; - return cec_add_elem(val); + cec_add_elem(val); + + return 0; } DEFINE_DEBUGFS_ATTRIBUTE(pfn_ops, u64_get, pfn_set, "0x%llx\n"); -- 2.20.1