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=-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 53E68C43381 for ; Thu, 11 Mar 2021 08:47:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 06D3A64FBB for ; Thu, 11 Mar 2021 08:47:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231546AbhCKIqj (ORCPT ); Thu, 11 Mar 2021 03:46:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231157AbhCKIq3 (ORCPT ); Thu, 11 Mar 2021 03:46:29 -0500 Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 77987C061574; Thu, 11 Mar 2021 00:46:27 -0800 (PST) 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=2UJb+wsmJ2 FcUp6+0rWvkv9WpaHiRbHAp+kj50P9o9U=; b=W6EknMUlXpOxz2ooLVWJL9ds6D dmTiHOpvqNM5cHU40h3qzWhcn4x9Q7++9SxnUkZ9wIhoGxEkocaRgpp5GjV3A6EP OQAjgREHpMzI1z/5ooZfvR7xy5HPyszF1fJ1gIFwHDAY+ZbHS5SQpkeNMHP0bpUg gSVzFnN8HS8mqq0sI= Received: from ubuntu.localdomain (unknown [114.214.226.60]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygDn7x_a2ElglukKAA--.3103S4; Thu, 11 Mar 2021 16:46:18 +0800 (CST) From: Lv Yunlong To: santosh.shilimkar@oracle.com, davem@davemloft.net, kuba@kernel.org Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-kernel@vger.kernel.org, Lv Yunlong Subject: [PATCH] net/rds: Fix a use after free in rds_message_map_pages Date: Thu, 11 Mar 2021 00:46:16 -0800 Message-Id: <20210311084616.12356-1-lyl2019@mail.ustc.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: LkAmygDn7x_a2ElglukKAA--.3103S4 X-Coremail-Antispam: 1UD129KBjvdXoWrZrW3JF4UCw4DXr4rKw15urg_yoWDGFg_uF WxJrn7W347XFyIkrs7KrsrAw4fZr1kXw18ua42qFn5tryDCFn5Xw48trn8uwnrCFW2vr1x C3yDXr93ua4kZjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbx8FF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j 6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr 1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IE rcIFxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14 v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkG c2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI 0_Jr0_Gr1lIxAIcVCF04k26cxKx2IYs7xG6rWUJVWrZr1UMIIF0xvEx4A2jsIE14v26r1j 6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQZ2 3UUUUU= X-CM-SenderInfo: ho1ojiyrz6zt1loo32lwfovvfxof0/ Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In rds_message_map_pages, rds_message_put() will free rm. Maybe store the value of rm->data.op_sg ahead of rds_message_put() is better. Otherwise other threads could allocate the freed chunk and may change the value of rm->data.op_sg. Signed-off-by: Lv Yunlong --- net/rds/message.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/rds/message.c b/net/rds/message.c index 071a261fdaab..392e3a2f41a0 100644 --- a/net/rds/message.c +++ b/net/rds/message.c @@ -347,8 +347,9 @@ struct rds_message *rds_message_map_pages(unsigned long *page_addrs, unsigned in rm->data.op_nents = DIV_ROUND_UP(total_len, PAGE_SIZE); rm->data.op_sg = rds_message_alloc_sgs(rm, num_sgs); if (IS_ERR(rm->data.op_sg)) { + struct scatterlist *tmp = rm->data.op_sg; rds_message_put(rm); - return ERR_CAST(rm->data.op_sg); + return ERR_CAST(tmp); } for (i = 0; i < rm->data.op_nents; ++i) { -- 2.25.1