From patchwork Tue Mar 23 02:58:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lv Yunlong X-Patchwork-Id: 12156689 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=-18.8 required=3.0 tests=BAYES_00,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=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 D2962C433DB for ; Tue, 23 Mar 2021 02:59:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 983B361998 for ; Tue, 23 Mar 2021 02:59:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229574AbhCWC7V (ORCPT ); Mon, 22 Mar 2021 22:59:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229482AbhCWC7H (ORCPT ); Mon, 22 Mar 2021 22:59:07 -0400 Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 317B4C061574; Mon, 22 Mar 2021 19:58:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mail.ustc.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:MIME-Version:Content-Transfer-Encoding; bh=6nGflbw2M1 nIAUTSCNcXju9H6GH0cycjGJaL9m/nRSQ=; b=j2XvpBSWRPZBPZvAHsLRH6+C1W fqDtDX3Z26z0fnwnPyDannxRz0TavFTWo8wG58SSkNH5QQrrYCAPnKvJMfuu8FWh Rpx0CaH4knOASrlqcWSw0M0zTzWs+hjY63uOpd9/C9dnslqtqoDNstrva1gK8u0r /dPkclKgSkvjXkX0s= Received: from ubuntu.localdomain (unknown [202.38.69.14]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygBHTkpuWVlgfX4ZAA--.517S4; Tue, 23 Mar 2021 10:58:54 +0800 (CST) From: Lv Yunlong To: martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-kernel@vger.kernel.org, Lv Yunlong Subject: [PATCH] target: Fix a double put in transport_free_session Date: Mon, 22 Mar 2021 19:58:51 -0700 Message-Id: <20210323025851.11782-1-lyl2019@mail.ustc.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-CM-TRANSID: LkAmygBHTkpuWVlgfX4ZAA--.517S4 X-Coremail-Antispam: 1UD129KBjvdXoWrtF17tr1xtrW5uFyxJr15XFb_yoWkAFb_CF 1F9wnrWF1Fgw4DKr47G3W3Xry2yF9Y9F1IvFs2k3yjgrykZF1rJrnrJFn3u34jkrWrZryF yrnFyr1Dur4UXjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbVxFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j 6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr 1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IE rcIFxwCY02Avz4vE14v_Gr1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr 1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE 14v26r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7 IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8VAvwI8IcIk0rVWrJr0_WFyUJwCI42IY 6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa 73UjIFyTuYvjfUO6pBUUUUU X-CM-SenderInfo: ho1ojiyrz6zt1loo32lwfovvfxof0/ Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org In transport_free_session, se_nacl is got from se_sess with the initial reference. If se_nacl->acl_sess_list is empty, se_nacl->dynamic_stop is set to true. Then the first target_put_nacl(se_nacl) will drop the initial reference and free se_nacl. Later there is a second target_put_nacl() to put se_nacl. It may cause error in race. My patch sets se_nacl->dynamic_stop to false to avoid the double put. Signed-off-by: Lv Yunlong --- drivers/target/target_core_transport.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 5ecb9f18a53d..c266defe694f 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -584,8 +584,10 @@ void transport_free_session(struct se_session *se_sess) } mutex_unlock(&se_tpg->acl_node_mutex); - if (se_nacl->dynamic_stop) + if (se_nacl->dynamic_stop) { target_put_nacl(se_nacl); + se_nacl->dynamic_stop = false; + } target_put_nacl(se_nacl); }