From patchwork Tue Jun 23 19:55:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 223139 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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 ECBEFC433DF for ; Tue, 23 Jun 2020 21:28:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4CAB20724 for ; Tue, 23 Jun 2020 21:28:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592947709; bh=iIu7yHtK80ljItvjvrWJOIhey9o7CF3Lqvyv/NYgzCU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GVs02s6hF915bRA4isiv13yrutWAH2zdLXjGf7hzg0JtLNLS4qE4Px0YgfTJNrmI+ aaNRF3UtHIYIwv3Kl8jgHqlLdLKC5D0a3Mb1ZffpR34Ppr9ARWc5jf8+kRRcIYMGOa uGe4RyL9g0k8c9rbYFDCVmpBKbOfMmxLycw5KOMk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388135AbgFWUP6 (ORCPT ); Tue, 23 Jun 2020 16:15:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:59070 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388441AbgFWUPy (ORCPT ); Tue, 23 Jun 2020 16:15:54 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 B329E2064B; Tue, 23 Jun 2020 20:15:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592943354; bh=iIu7yHtK80ljItvjvrWJOIhey9o7CF3Lqvyv/NYgzCU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KJc1nKDsLh4pp6BOfCpcPeA0iYDmzdQQL+5uCyNqf9eLDzribE+3gyovCT/s5K7Hp gVZuMt9Z3JiiIy60nMwe07TO3gYYKYX+zFh7rZfT5QA/ORZuArdw5JYznf66FRCjcd KA9f4F2GCq/LlWjY+6jf0aeWqpXt+YCnyXeZVVV8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, dihu , Alexei Starovoitov , John Fastabend , Jakub Sitnicki , Sasha Levin Subject: [PATCH 5.7 359/477] bpf/sockmap: Fix kernel panic at __tcp_bpf_recvmsg Date: Tue, 23 Jun 2020 21:55:56 +0200 Message-Id: <20200623195424.505239623@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200623195407.572062007@linuxfoundation.org> References: <20200623195407.572062007@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: dihu [ Upstream commit 487082fb7bd2a32b66927d2b22e3a81b072b44f0 ] When user application calls read() with MSG_PEEK flag to read data of bpf sockmap socket, kernel panic happens at __tcp_bpf_recvmsg+0x12c/0x350. sk_msg is not removed from ingress_msg queue after read out under MSG_PEEK flag is set. Because it's not judged whether sk_msg is the last msg of ingress_msg queue, the next sk_msg may be the head of ingress_msg queue, whose memory address of sg page is invalid. So it's necessary to add check codes to prevent this problem. [20759.125457] BUG: kernel NULL pointer dereference, address: 0000000000000008 [20759.132118] CPU: 53 PID: 51378 Comm: envoy Tainted: G E 5.4.32 #1 [20759.140890] Hardware name: Inspur SA5212M4/YZMB-00370-109, BIOS 4.1.12 06/18/2017 [20759.149734] RIP: 0010:copy_page_to_iter+0xad/0x300 [20759.270877] __tcp_bpf_recvmsg+0x12c/0x350 [20759.276099] tcp_bpf_recvmsg+0x113/0x370 [20759.281137] inet_recvmsg+0x55/0xc0 [20759.285734] __sys_recvfrom+0xc8/0x130 [20759.290566] ? __audit_syscall_entry+0x103/0x130 [20759.296227] ? syscall_trace_enter+0x1d2/0x2d0 [20759.301700] ? __audit_syscall_exit+0x1e4/0x290 [20759.307235] __x64_sys_recvfrom+0x24/0x30 [20759.312226] do_syscall_64+0x55/0x1b0 [20759.316852] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: dihu Signed-off-by: Alexei Starovoitov Acked-by: John Fastabend Acked-by: Jakub Sitnicki Link: https://lore.kernel.org/bpf/20200605084625.9783-1-anny.hu@linux.alibaba.com Signed-off-by: Sasha Levin --- net/ipv4/tcp_bpf.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c index 9c5540887fbe5..7aa68f4aae6c3 100644 --- a/net/ipv4/tcp_bpf.c +++ b/net/ipv4/tcp_bpf.c @@ -64,6 +64,9 @@ int __tcp_bpf_recvmsg(struct sock *sk, struct sk_psock *psock, } while (i != msg_rx->sg.end); if (unlikely(peek)) { + if (msg_rx == list_last_entry(&psock->ingress_msg, + struct sk_msg, list)) + break; msg_rx = list_next_entry(msg_rx, list); continue; }