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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADB9BC4332F for ; Tue, 5 Apr 2022 12:56:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356767AbiDEMun (ORCPT ); Tue, 5 Apr 2022 08:50:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243772AbiDEJJQ (ORCPT ); Tue, 5 Apr 2022 05:09:16 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AC5ECB00F; Tue, 5 Apr 2022 01:58:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id B11D961476; Tue, 5 Apr 2022 08:58:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C172BC385A0; Tue, 5 Apr 2022 08:58:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649149114; bh=vjsrtqUyE3qmQ6zDoHeGzm8tnzALeS3OuodQrayDuPM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eMolNrFsF4126WH58f4PlHGsLiz9hs4YikRzPMdg+/O4BK1xIczgkKdpC/5hPahfY My9pxdG+4jdxAF9JPYOC6K/fHUtbFdoJ9hvKl+pbzao/orGxwG3IdyFBcQFP8oUGw4 Ml3EmqYgXxdjihr52v/B12Opq7jCcE1dY8kzcu4U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wang Yufen , Daniel Borkmann , John Fastabend , Sasha Levin Subject: [PATCH 5.16 0600/1017] bpf, sockmap: Fix memleak in tcp_bpf_sendmsg while sk msg is full Date: Tue, 5 Apr 2022 09:25:13 +0200 Message-Id: <20220405070412.088227343@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070354.155796697@linuxfoundation.org> References: <20220405070354.155796697@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: Wang Yufen [ Upstream commit 9c34e38c4a870eb30b13f42f5b44f42e9d19ccb8 ] If tcp_bpf_sendmsg() is running while sk msg is full. When sk_msg_alloc() returns -ENOMEM error, tcp_bpf_sendmsg() goes to wait_for_memory. If partial memory has been alloced by sk_msg_alloc(), that is, msg_tx->sg.size is greater than osize after sk_msg_alloc(), memleak occurs. To fix we use sk_msg_trim() to release the allocated memory, then goto wait for memory. Other call paths of sk_msg_alloc() have the similar issue, such as tls_sw_sendmsg(), so handle sk_msg_trim logic inside sk_msg_alloc(), as Cong Wang suggested. This issue can cause the following info: WARNING: CPU: 3 PID: 7950 at net/core/stream.c:208 sk_stream_kill_queues+0xd4/0x1a0 Call Trace: inet_csk_destroy_sock+0x55/0x110 __tcp_close+0x279/0x470 tcp_close+0x1f/0x60 inet_release+0x3f/0x80 __sock_release+0x3d/0xb0 sock_close+0x11/0x20 __fput+0x92/0x250 task_work_run+0x6a/0xa0 do_exit+0x33b/0xb60 do_group_exit+0x2f/0xa0 get_signal+0xb6/0x950 arch_do_signal_or_restart+0xac/0x2a0 exit_to_user_mode_prepare+0xa9/0x200 syscall_exit_to_user_mode+0x12/0x30 do_syscall_64+0x46/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae WARNING: CPU: 3 PID: 2094 at net/ipv4/af_inet.c:155 inet_sock_destruct+0x13c/0x260 Call Trace: __sk_destruct+0x24/0x1f0 sk_psock_destroy+0x19b/0x1c0 process_one_work+0x1b3/0x3c0 kthread+0xe6/0x110 ret_from_fork+0x22/0x30 Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Wang Yufen Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20220304081145.2037182-3-wangyufen@huawei.com Signed-off-by: Sasha Levin --- net/core/skmsg.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 929a2b096b04..cc381165ea08 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -27,6 +27,7 @@ int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len, int elem_first_coalesce) { struct page_frag *pfrag = sk_page_frag(sk); + u32 osize = msg->sg.size; int ret = 0; len -= msg->sg.size; @@ -35,13 +36,17 @@ int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len, u32 orig_offset; int use, i; - if (!sk_page_frag_refill(sk, pfrag)) - return -ENOMEM; + if (!sk_page_frag_refill(sk, pfrag)) { + ret = -ENOMEM; + goto msg_trim; + } orig_offset = pfrag->offset; use = min_t(int, len, pfrag->size - orig_offset); - if (!sk_wmem_schedule(sk, use)) - return -ENOMEM; + if (!sk_wmem_schedule(sk, use)) { + ret = -ENOMEM; + goto msg_trim; + } i = msg->sg.end; sk_msg_iter_var_prev(i); @@ -71,6 +76,10 @@ int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len, } return ret; + +msg_trim: + sk_msg_trim(sk, msg, osize); + return ret; } EXPORT_SYMBOL_GPL(sk_msg_alloc); -- 2.34.1