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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 2E0E8C6786C for ; Fri, 14 Dec 2018 12:01:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E79CE2146E for ; Fri, 14 Dec 2018 12:01:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544788897; bh=WlgoTDTRuy/2tdn2El5d8nTmsm9ijnKXWt67VEHbng8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=EitOUCsolJrJLOiWaGjSfqs+lv8IXADVG5DMGoPj/zoEmlftONWiET7Ha+U1Tg07l Vjy0njT/n7pSQj32WSud4lX3cTtPUaaDK3OGyZAe294P7KZbGYYw3NJATsOompg650 DKNHY7iEujny+wj7/7wyxEbl7EfIZtLFNb5oqPyU= DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E79CE2146E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729790AbeLNMBg (ORCPT ); Fri, 14 Dec 2018 07:01:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:43996 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729754AbeLNMBc (ORCPT ); Fri, 14 Dec 2018 07:01:32 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0B46521104; Fri, 14 Dec 2018 12:01:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544788891; bh=WlgoTDTRuy/2tdn2El5d8nTmsm9ijnKXWt67VEHbng8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=L4HtoRLNALT4LEkO1L7boX86lzUZyGe667tt2IwhuvYFe0eQjjax5sdSLsbKn3Xl4 P3yWXSf/h8kE6AC0+9DuJR5l+CICIyjm7gCmB5y5XzZwRw/ZVqz2s0sAwxeM3/KAC2 jedWnCtjxD7yN1Dnr6J22dTVaV0jXHUZody0yIhA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+0b05d8aa7cb185107483@syzkaller.appspotmail.com, syzbot+aad231d51b1923158444@syzkaller.appspotmail.com, Neil Horman , Xin Long , Marcelo Ricardo Leitner , "David S. Miller" Subject: [PATCH 4.19 013/142] sctp: kfree_rcu asoc Date: Fri, 14 Dec 2018 12:58:18 +0100 Message-Id: <20181214115747.578786199@linuxfoundation.org> X-Mailer: git-send-email 2.20.0 In-Reply-To: <20181214115747.053633987@linuxfoundation.org> References: <20181214115747.053633987@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit fb6df5a6234c38a9c551559506a49a677ac6f07a ] In sctp_hash_transport/sctp_epaddr_lookup_transport, it dereferences a transport's asoc under rcu_read_lock while asoc is freed not after a grace period, which leads to a use-after-free panic. This patch fixes it by calling kfree_rcu to make asoc be freed after a grace period. Note that only the asoc's memory is delayed to free in the patch, it won't cause sk to linger longer. Thanks Neil and Marcelo to make this clear. Fixes: 7fda702f9315 ("sctp: use new rhlist interface on sctp transport rhashtable") Fixes: cd2b70875058 ("sctp: check duplicate node before inserting a new transport") Reported-by: syzbot+0b05d8aa7cb185107483@syzkaller.appspotmail.com Reported-by: syzbot+aad231d51b1923158444@syzkaller.appspotmail.com Suggested-by: Neil Horman Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/sctp/structs.h | 2 ++ net/sctp/associola.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -2075,6 +2075,8 @@ struct sctp_association { __u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1]; __u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1]; + + struct rcu_head rcu; }; --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -434,7 +434,7 @@ static void sctp_association_destroy(str WARN_ON(atomic_read(&asoc->rmem_alloc)); - kfree(asoc); + kfree_rcu(asoc, rcu); SCTP_DBG_OBJCNT_DEC(assoc); }