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,DKIMWL_WL_HIGH, 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 C7751C43460 for ; Mon, 12 Apr 2021 09:35:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E59E61277 for ; Mon, 12 Apr 2021 09:35:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240754AbhDLJfd (ORCPT ); Mon, 12 Apr 2021 05:35:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:33550 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240280AbhDLJKL (ORCPT ); Mon, 12 Apr 2021 05:10:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8ED5561221; Mon, 12 Apr 2021 09:05:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618218307; bh=E4On03olDXlXaD6Da4m40Fka5Ezpp6tXS7AB3kXFs14=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZrxVyXxNISLkFe8JdqAMCPFW+CxfwcaqojsHEaLAajpCZoO9MPAmID8986GDQm7xe oPEVb3YvDFpDXYBkvBAsmXbwpOGYea8Ys6OFMpkzXWUY2QDF4uDReBLHDzMFz011q5 DpBWn6BrW7kuKIlT2yxeb4B+t4yxPE4dKjLcufKc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lv Yunlong , =?UTF-8?q?H=C3=A5kon=20Bugge?= , "David S. Miller" , Sasha Levin Subject: [PATCH 5.11 148/210] net/rds: Fix a use after free in rds_message_map_pages Date: Mon, 12 Apr 2021 10:40:53 +0200 Message-Id: <20210412084020.920406302@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084016.009884719@linuxfoundation.org> References: <20210412084016.009884719@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lv Yunlong [ Upstream commit bdc2ab5c61a5c07388f4820ff21e787b4dfd1ced ] In rds_message_map_pages, the rm is freed by rds_message_put(rm). But rm is still used by rm->data.op_sg in return value. My patch assigns ERR_CAST(rm->data.op_sg) to err before the rm is freed to avoid the uaf. Fixes: 7dba92037baf3 ("net/rds: Use ERR_PTR for rds_message_alloc_sgs()") Signed-off-by: Lv Yunlong Reviewed-by: Håkon Bugge Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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..799034e0f513 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)) { + void *err = ERR_CAST(rm->data.op_sg); rds_message_put(rm); - return ERR_CAST(rm->data.op_sg); + return err; } for (i = 0; i < rm->data.op_nents; ++i) { -- 2.30.2