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 17B76C46467 for ; Wed, 28 Dec 2022 16:14:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234540AbiL1QOg (ORCPT ); Wed, 28 Dec 2022 11:14:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234488AbiL1QOK (ORCPT ); Wed, 28 Dec 2022 11:14:10 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C40B4183B7 for ; Wed, 28 Dec 2022 08:12:08 -0800 (PST) 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 60A4B61576 for ; Wed, 28 Dec 2022 16:12:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70E53C433EF; Wed, 28 Dec 2022 16:12:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672243927; bh=4fwTmJSony6tMREeZYaqH9q0yVlRdm4LJSLAbp406no=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pbZabZzxomQNKUjLQbYaXnGO87d8edcnNUcN/lb7hyg5xcyB2Ve3q5Vd8g/H9J11J +kxiCGURKv6quwtskfU27D0P6rkTH3mlXsCgXxDikRUWil6WNzw35U/TKELgC4b8si IKia+lSrB8mg+xaHruX84ZpbqOf2N7X9w8qwvQZg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daniel Jordan , Herbert Xu , Sasha Levin Subject: [PATCH 6.0 0617/1073] padata: Fix list iterator in padata_do_serial() Date: Wed, 28 Dec 2022 15:36:45 +0100 Message-Id: <20221228144344.801669372@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144328.162723588@linuxfoundation.org> References: <20221228144328.162723588@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: Daniel Jordan [ Upstream commit 57ddfecc72a6c9941d159543e1c0c0a74fe9afdd ] list_for_each_entry_reverse() assumes that the iterated list is nonempty and that every list_head is embedded in the same type, but its use in padata_do_serial() breaks both rules. This doesn't cause any issues now because padata_priv and padata_list happen to have their list fields at the same offset, but we really shouldn't be relying on that. Fixes: bfde23ce200e ("padata: unbind parallel jobs from specific CPUs") Signed-off-by: Daniel Jordan Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- kernel/padata.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/kernel/padata.c b/kernel/padata.c index 97f51e0c1776..de90af5fcbe6 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -390,13 +390,16 @@ void padata_do_serial(struct padata_priv *padata) int hashed_cpu = padata_cpu_hash(pd, padata->seq_nr); struct padata_list *reorder = per_cpu_ptr(pd->reorder_list, hashed_cpu); struct padata_priv *cur; + struct list_head *pos; spin_lock(&reorder->lock); /* Sort in ascending order of sequence number. */ - list_for_each_entry_reverse(cur, &reorder->list, list) + list_for_each_prev(pos, &reorder->list) { + cur = list_entry(pos, struct padata_priv, list); if (cur->seq_nr < padata->seq_nr) break; - list_add(&padata->list, &cur->list); + } + list_add(&padata->list, pos); spin_unlock(&reorder->lock); /* -- 2.35.1