From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F93F26281 for ; Sun, 8 Sep 2024 18:36:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725820586; cv=none; b=uUSJy3lxQQEM0dwMAleRQPa0AdGjAoM3F+I+XGyfaLyQvqp/dsldWPw8D5stWOUfY5z0pGyOUvv+yek89Tc5Hb7GZQIbw93UmcvOBKyQePhkWv1CAGTlfkR6UFNNS9F4UGn2ZIl914BCM/3rtFdtHIu2BIvCPlWoEu7MjOx7jOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725820586; c=relaxed/simple; bh=eERNCsREQgK0GZ6ycgemDK29lrpf7PMtl0is3WX1RTo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=b3/9KKE8F6zjZE/YfbifLHhnp4Kc7JHKcowLD4nkw8tGGc8EK/Z7UCA6wnxx9Br3dNQDu41w6iQQ3yNIb3CnpVk7ZP/pubnhfOW75e9xdhm61TaFHNPIbio7DTzR4GZPD4eTo2SFoYiGvjzCC/SOID2YIQAhbwiHFBO4vMGijLo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=nVf9M5B0; arc=none smtp.client-ip=209.85.214.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nVf9M5B0" Received: by mail-pl1-f169.google.com with SMTP id d9443c01a7336-2057c6c57b5so19257035ad.1 for ; Sun, 08 Sep 2024 11:36:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1725820585; x=1726425385; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=z2DVWv3yluWRsd6jNRr0BJIPwVpgo1u2tqMtNigqFi4=; b=nVf9M5B0lzYmSi+FgpFL1sryaddG8F1mFmTM7SINX0pSQXdoPFu0JL61n6RKDO9M+y xoMYTORY8ZcvenS1jjbAWT8nUdBnEy+UJfB74M2NQHctFW46SO+UIInjOVr5CXoFyOG8 8Tzr7B0wEmSvy1HmRjJ19ajIWHou3+UAgg3iMLhYMYGB2yZoW6g7+3ii5gxAQS9eywc7 4KQcT35UOnfSSMPaxCVX/bvJeDLS0KItf6R+FBbvtDaFIQR0G/AfkXFXg6tUnewmwf8N KsWgN8uZD+3nUrsy6te6E2Va7UNDx4yadWq5eic6vtB/rSbGI+awicMM4la8qX85DZQg KsZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725820585; x=1726425385; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=z2DVWv3yluWRsd6jNRr0BJIPwVpgo1u2tqMtNigqFi4=; b=BrlVCe5c5JeHTDqVg8c4go/wRkKMpj7D6Cp/dpWWMcymnWGwU9Di10pqdHV5VAZbY9 RMq50P5gB2HiIiok9UFi58ZhEaz40fgWOy7HOPw7Qd088Cqs9AkHvbE0YhtSOGGV/FJE N61Re/mpAyS+b7YMFSRS4res22quOlKPCU5QfKSzUuc7uzWgos8AJc8Ec4yzOpe4clkn frstEAmUCVWXjWlclCu3LLhiG3q85S1q7ZycTErAjJ/hZwO2luaO9NA/N07bN6jCGU73 f6sereqYODop5bxUwS2HTYbCoud/R/7HzuCVjvToSkRJoYOhLu3bfGZqlR4oI6+DRcws xyOw== X-Forwarded-Encrypted: i=1; AJvYcCX8qSskSgerOJ/Q8N/BG26BjQlWX38FJ8Xi8xyiZTJHb8FCpruFi+SxF+DMV+bsICw5JfJPD6U=@vger.kernel.org X-Gm-Message-State: AOJu0YyWILzjW07W4HIcu13hZ8H4fjoy6QCe7Ocv8b0S/CWBZmtvoM2d UrB4s/A3OahWbxxomZs8Ce7LCCzqi6g3JbNaMw/E+4cg7t/0XeGk X-Google-Smtp-Source: AGHT+IFLPbhYx1ec+fAA6mvnDRKPqO3Y9GWWTfWWEuqgKW0131S3ar4VrdLFm01sL5KvH9x4HRK3rA== X-Received: by 2002:a17:903:2350:b0:202:3617:d52a with SMTP id d9443c01a7336-206ee9256f1mr131298255ad.6.1725820584616; Sun, 08 Sep 2024 11:36:24 -0700 (PDT) Received: from localhost ([2601:647:6881:9060:4334:4d08:284:9405]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-20710e0ed43sm22252805ad.50.2024.09.08.11.36.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Sep 2024 11:36:24 -0700 (PDT) Date: Sun, 8 Sep 2024 11:36:23 -0700 From: Cong Wang To: Dmitry Antipov Cc: John Fastabend , Jakub Sitnicki , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, lvc-project@linuxtesting.org Subject: Re: [PATCH RFC net] net: sockmap: avoid race between sock_map_destroy() and sk_psock_put() Message-ID: References: <20240905064257.3870271-1-dmantipov@yandex.ru> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240905064257.3870271-1-dmantipov@yandex.ru> On Thu, Sep 05, 2024 at 09:42:57AM +0300, Dmitry Antipov wrote: > At https://syzkaller.appspot.com/bug?extid=f363afac6b0ace576f45, syzbot > has triggered the following race condition: Are you sure it is due to sockmap code? I see rds_tcp_accept_one() in the stack trace. This is why I highly suspect that it is due to RDS code instead of sockmap code. I have the following patch ready for testing, in case you are interested. Thanks. ---------------> commit 4068420e2c82137ab95d387346c0776a36c69e5d Author: Cong Wang Date: Sun Sep 1 17:01:49 2024 -0700 rds: check sock->sk->sk_user_data conflicts Signed-off-by: Cong Wang diff --git a/net/rds/tcp.c b/net/rds/tcp.c index 351ac1747224..54ee7f6b8f34 100644 --- a/net/rds/tcp.c +++ b/net/rds/tcp.c @@ -134,11 +134,12 @@ void rds_tcp_restore_callbacks(struct socket *sock, * it is set. The absence of RDS_CONN_UP bit protects those paths * from being called while it isn't set. */ -void rds_tcp_reset_callbacks(struct socket *sock, - struct rds_conn_path *cp) +int rds_tcp_reset_callbacks(struct socket *sock, + struct rds_conn_path *cp) { struct rds_tcp_connection *tc = cp->cp_transport_data; struct socket *osock = tc->t_sock; + int ret = 0; if (!osock) goto newsock; @@ -181,21 +182,25 @@ void rds_tcp_reset_callbacks(struct socket *sock, newsock: rds_send_path_reset(cp); lock_sock(sock->sk); - rds_tcp_set_callbacks(sock, cp); + ret = rds_tcp_set_callbacks(sock, cp); release_sock(sock->sk); + return ret; } /* Add tc to rds_tcp_tc_list and set tc->t_sock. See comments * above rds_tcp_reset_callbacks for notes about synchronization * with data path */ -void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp) +int rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp) { struct rds_tcp_connection *tc = cp->cp_transport_data; - rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc); write_lock_bh(&sock->sk->sk_callback_lock); - + if (sock->sk->sk_user_data) { + write_unlock_bh(&sock->sk->sk_callback_lock); + return -EBUSY; + } + rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc); /* done under the callback_lock to serialize with write_space */ spin_lock(&rds_tcp_tc_list_lock); list_add_tail(&tc->t_list_item, &rds_tcp_tc_list); @@ -222,6 +227,7 @@ void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp) sock->sk->sk_state_change = rds_tcp_state_change; write_unlock_bh(&sock->sk->sk_callback_lock); + return 0; } /* Handle RDS_INFO_TCP_SOCKETS socket option. It only returns IPv4 diff --git a/net/rds/tcp.h b/net/rds/tcp.h index 053aa7da87ef..710cc7fa41af 100644 --- a/net/rds/tcp.h +++ b/net/rds/tcp.h @@ -50,8 +50,8 @@ struct rds_tcp_statistics { /* tcp.c */ bool rds_tcp_tune(struct socket *sock); -void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp); -void rds_tcp_reset_callbacks(struct socket *sock, struct rds_conn_path *cp); +int rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp); +int rds_tcp_reset_callbacks(struct socket *sock, struct rds_conn_path *cp); void rds_tcp_restore_callbacks(struct socket *sock, struct rds_tcp_connection *tc); u32 rds_tcp_write_seq(struct rds_tcp_connection *tc); diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index d89bd8d0c354..695456455aee 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -205,11 +205,15 @@ int rds_tcp_accept_one(struct socket *sock) goto rst_nsk; if (rs_tcp->t_sock) { /* Duelling SYN has been handled in rds_tcp_accept_one() */ - rds_tcp_reset_callbacks(new_sock, cp); + ret = rds_tcp_reset_callbacks(new_sock, cp); + if (ret) + goto rst_nsk; /* rds_connect_path_complete() marks RDS_CONN_UP */ rds_connect_path_complete(cp, RDS_CONN_RESETTING); } else { - rds_tcp_set_callbacks(new_sock, cp); + ret = rds_tcp_set_callbacks(new_sock, cp); + if (ret) + goto rst_nsk; rds_connect_path_complete(cp, RDS_CONN_CONNECTING); } new_sock = NULL;