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 0E24CC76188 for ; Mon, 3 Apr 2023 14:20:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233176AbjDCOUd (ORCPT ); Mon, 3 Apr 2023 10:20:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40694 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233132AbjDCOUK (ORCPT ); Mon, 3 Apr 2023 10:20:10 -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 3F48F312B1 for ; Mon, 3 Apr 2023 07:19:55 -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 8E5B461D16 for ; Mon, 3 Apr 2023 14:19:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4C63C433EF; Mon, 3 Apr 2023 14:19:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680531594; bh=75h4lD0mk5zmLz+UDOKXhH8iMe3itMJ/s4s7lr3PM7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UIG8EPpKOetaDltcyOqaxA9+ly2QugSHXBprHkTpTWS9ldrX5tiFeMvC0E2vzfwam umQej31+wx5n4xmLCfj7D2TeR5fPE88Imhhw5uLh+UM2jjExm3/VR99H2I/bEVSzfc uBc4zBpkdhoKudcVb2hy+ho6Lr0vhAiSx3Of/Udc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jakob Koschel , Justin Tee , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 5.4 038/104] scsi: lpfc: Avoid usage of list iterator variable after loop Date: Mon, 3 Apr 2023 16:08:30 +0200 Message-Id: <20230403140405.860636053@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403140403.549815164@linuxfoundation.org> References: <20230403140403.549815164@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: Jakob Koschel [ Upstream commit 2850b23e9f9ae3696e472d2883ea1b43aafa884e ] If the &epd_pool->list is empty when executing lpfc_get_io_buf_from_expedite_pool() the function would return an invalid pointer. Even in the case if the list is guaranteed to be populated, the iterator variable should not be used after the loop to be more robust for future changes. Linus proposed to avoid any use of the list iterator variable after the loop, in the attempt to move the list iterator variable declaration into the macro to avoid any potential misuse after the loop [1]. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1] Signed-off-by: Jakob Koschel Link: https://lore.kernel.org/r/20230301-scsi-lpfc-avoid-list-iterator-after-loop-v1-1-325578ae7561@gmail.com Reviewed-by: Justin Tee Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/lpfc/lpfc_sli.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c index bd908dd273078..e489c68cfb631 100644 --- a/drivers/scsi/lpfc/lpfc_sli.c +++ b/drivers/scsi/lpfc/lpfc_sli.c @@ -20407,20 +20407,20 @@ lpfc_get_io_buf_from_private_pool(struct lpfc_hba *phba, static struct lpfc_io_buf * lpfc_get_io_buf_from_expedite_pool(struct lpfc_hba *phba) { - struct lpfc_io_buf *lpfc_ncmd; + struct lpfc_io_buf *lpfc_ncmd = NULL, *iter; struct lpfc_io_buf *lpfc_ncmd_next; unsigned long iflag; struct lpfc_epd_pool *epd_pool; epd_pool = &phba->epd_pool; - lpfc_ncmd = NULL; spin_lock_irqsave(&epd_pool->lock, iflag); if (epd_pool->count > 0) { - list_for_each_entry_safe(lpfc_ncmd, lpfc_ncmd_next, + list_for_each_entry_safe(iter, lpfc_ncmd_next, &epd_pool->list, list) { - list_del(&lpfc_ncmd->list); + list_del(&iter->list); epd_pool->count--; + lpfc_ncmd = iter; break; } } -- 2.39.2