From patchwork Tue Aug 23 13:37:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Jian X-Patchwork-Id: 12952332 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85C66C32796 for ; Tue, 23 Aug 2022 17:07:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343931AbiHWRHe (ORCPT ); Tue, 23 Aug 2022 13:07:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345020AbiHWRGS (ORCPT ); Tue, 23 Aug 2022 13:06:18 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76A1212B07D for ; Tue, 23 Aug 2022 06:35:09 -0700 (PDT) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4MBqqZ01s7zXdkv; Tue, 23 Aug 2022 21:30:49 +0800 (CST) Received: from huawei.com (10.175.101.6) by canpemm500010.china.huawei.com (7.192.105.118) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 23 Aug 2022 21:35:06 +0800 From: Liu Jian To: , , , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH bpf-next v2 1/2] net: If the sock is dead, do not access sock's sk_wq in sk_stream_wait_memory Date: Tue, 23 Aug 2022 21:37:54 +0800 Message-ID: <20220823133755.314697-2-liujian56@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220823133755.314697-1-liujian56@huawei.com> References: <20220823133755.314697-1-liujian56@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Fix the below NULL pointer dereference: [ 14.471200] Call Trace: [ 14.471562] [ 14.471882] lock_acquire+0x245/0x2e0 [ 14.472416] ? remove_wait_queue+0x12/0x50 [ 14.473014] ? _raw_spin_lock_irqsave+0x17/0x50 [ 14.473681] _raw_spin_lock_irqsave+0x3d/0x50 [ 14.474318] ? remove_wait_queue+0x12/0x50 [ 14.474907] remove_wait_queue+0x12/0x50 [ 14.475480] sk_stream_wait_memory+0x20d/0x340 [ 14.476127] ? do_wait_intr_irq+0x80/0x80 [ 14.476704] do_tcp_sendpages+0x287/0x600 [ 14.477283] tcp_bpf_push+0xab/0x260 [ 14.477817] tcp_bpf_sendmsg_redir+0x297/0x500 [ 14.478461] ? __local_bh_enable_ip+0x77/0xe0 [ 14.479096] tcp_bpf_send_verdict+0x105/0x470 [ 14.479729] tcp_bpf_sendmsg+0x318/0x4f0 [ 14.480311] sock_sendmsg+0x2d/0x40 [ 14.480822] ____sys_sendmsg+0x1b4/0x1c0 [ 14.481390] ? copy_msghdr_from_user+0x62/0x80 [ 14.482048] ___sys_sendmsg+0x78/0xb0 [ 14.482580] ? vmf_insert_pfn_prot+0x91/0x150 [ 14.483215] ? __do_fault+0x2a/0x1a0 [ 14.483738] ? do_fault+0x15e/0x5d0 [ 14.484246] ? __handle_mm_fault+0x56b/0x1040 [ 14.484874] ? lock_is_held_type+0xdf/0x130 [ 14.485474] ? find_held_lock+0x2d/0x90 [ 14.486046] ? __sys_sendmsg+0x41/0x70 [ 14.486587] __sys_sendmsg+0x41/0x70 [ 14.487105] ? intel_pmu_drain_pebs_core+0x350/0x350 [ 14.487822] do_syscall_64+0x34/0x80 [ 14.488345] entry_SYSCALL_64_after_hwframe+0x63/0xcd The test scene as following flow: thread1 thread2 ----------- --------------- tcp_bpf_sendmsg tcp_bpf_send_verdict tcp_bpf_sendmsg_redir sock_close tcp_bpf_push_locked __sock_release tcp_bpf_push //inet_release do_tcp_sendpages sock->ops->release sk_stream_wait_memory // tcp_close sk_wait_event sk->sk_prot->close release_sock(__sk); *** lock_sock(sk); __tcp_close sock_orphan(sk) sk->sk_wq = NULL release_sock **** lock_sock(__sk); remove_wait_queue(sk_sleep(sk), &wait); sk_sleep(sk) //NULL pointer dereference &rcu_dereference_raw(sk->sk_wq)->wait While waiting for memory in thread1, the socket is released with its wait queue because thread2 has closed it. This caused by tcp_bpf_send_verdict didn't increase the f_count of psock->sk_redir->sk_socket->file in thread1. We should check if SOCK_DEAD flag is set on wakeup in sk_stream_wait_memory, before accessing the wait queue. Suggested-by: Jakub Sitnicki Signed-off-by: Liu Jian Acked-by: John Fastabend --- v1->v2: As Jakub's suggested, check sock's DEAD flag before accessing the wait queue. net/core/stream.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/core/stream.c b/net/core/stream.c index ccc083cdef23..1105057ce00a 100644 --- a/net/core/stream.c +++ b/net/core/stream.c @@ -159,7 +159,8 @@ int sk_stream_wait_memory(struct sock *sk, long *timeo_p) *timeo_p = current_timeo; } out: - remove_wait_queue(sk_sleep(sk), &wait); + if (!sock_flag(sk, SOCK_DEAD)) + remove_wait_queue(sk_sleep(sk), &wait); return err; do_error: From patchwork Tue Aug 23 13:37:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Jian X-Patchwork-Id: 12952330 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97E4AC32772 for ; Tue, 23 Aug 2022 17:07:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343895AbiHWRHc (ORCPT ); Tue, 23 Aug 2022 13:07:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345018AbiHWRGS (ORCPT ); Tue, 23 Aug 2022 13:06:18 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 759DD152C64 for ; Tue, 23 Aug 2022 06:35:10 -0700 (PDT) Received: from canpemm500010.china.huawei.com (unknown [172.30.72.55]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4MBqrW2mXMz1N7MB; Tue, 23 Aug 2022 21:31:39 +0800 (CST) Received: from huawei.com (10.175.101.6) by canpemm500010.china.huawei.com (7.192.105.118) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 23 Aug 2022 21:35:07 +0800 From: Liu Jian To: , , , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH bpf-next v2 2/2] selftests/bpf: Add wait send memory test for sockmap redirect Date: Tue, 23 Aug 2022 21:37:55 +0800 Message-ID: <20220823133755.314697-3-liujian56@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220823133755.314697-1-liujian56@huawei.com> References: <20220823133755.314697-1-liujian56@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500010.china.huawei.com (7.192.105.118) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add one test for wait redirect sock's send memory test for sockmap. Signed-off-by: Liu Jian --- tools/testing/selftests/bpf/test_sockmap.c | 42 ++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/tools/testing/selftests/bpf/test_sockmap.c b/tools/testing/selftests/bpf/test_sockmap.c index 0fbaccdc8861..95b9b45ad028 100644 --- a/tools/testing/selftests/bpf/test_sockmap.c +++ b/tools/testing/selftests/bpf/test_sockmap.c @@ -138,6 +138,7 @@ struct sockmap_options { bool data_test; bool drop_expected; bool check_recved_len; + bool tx_wait_mem; int iov_count; int iov_length; int rate; @@ -578,6 +579,10 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt, sent = sendmsg(fd, &msg, flags); if (!drop && sent < 0) { + if (opt->tx_wait_mem && errno == EACCES) { + errno = 0; + goto out_errno; + } perror("sendmsg loop error"); goto out_errno; } else if (drop && sent >= 0) { @@ -644,6 +649,15 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt, goto out_errno; } + if (opt->tx_wait_mem) { + FD_ZERO(&w); + FD_SET(fd, &w); + slct = select(max_fd + 1, NULL, NULL, &w, &timeout); + errno = 0; + close(fd); + goto out_errno; + } + errno = 0; if (peek_flag) { flags |= MSG_PEEK; @@ -752,6 +766,22 @@ static int sendmsg_test(struct sockmap_options *opt) return err; } + if (opt->tx_wait_mem) { + struct timeval timeout; + int rxtx_buf_len = 1024; + + timeout.tv_sec = 3; + timeout.tv_usec = 0; + + err = setsockopt(c2, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(struct timeval)); + err |= setsockopt(c2, SOL_SOCKET, SO_SNDBUFFORCE, &rxtx_buf_len, sizeof(int)); + err |= setsockopt(p2, SOL_SOCKET, SO_RCVBUFFORCE, &rxtx_buf_len, sizeof(int)); + if (err) { + perror("setsockopt failed()"); + return errno; + } + } + rxpid = fork(); if (rxpid == 0) { if (txmsg_pop || txmsg_start_pop) @@ -788,6 +818,9 @@ static int sendmsg_test(struct sockmap_options *opt) return errno; } + if (opt->tx_wait_mem) + close(c2); + txpid = fork(); if (txpid == 0) { if (opt->sendpage) @@ -1452,6 +1485,14 @@ static void test_txmsg_redir(int cgrp, struct sockmap_options *opt) test_send(opt, cgrp); } +static void test_txmsg_redir_wait_sndmem(int cgrp, struct sockmap_options *opt) +{ + txmsg_redir = 1; + opt->tx_wait_mem = true; + test_send_large(opt, cgrp); + opt->tx_wait_mem = false; +} + static void test_txmsg_drop(int cgrp, struct sockmap_options *opt) { txmsg_drop = 1; @@ -1800,6 +1841,7 @@ static int populate_progs(char *bpf_file) struct _test test[] = { {"txmsg test passthrough", test_txmsg_pass}, {"txmsg test redirect", test_txmsg_redir}, + {"txmsg test redirect wait send mem", test_txmsg_redir_wait_sndmem}, {"txmsg test drop", test_txmsg_drop}, {"txmsg test ingress redirect", test_txmsg_ingress_redir}, {"txmsg test skb", test_txmsg_skb},