From nobody Sun Nov 24 07:22:07 2024 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.3]) by smtp.subspace.kernel.org (Postfix) with ESMTP id BEB9D1E04BA; Wed, 6 Nov 2024 12:45:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.3 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730897140; cv=none; b=isyyCPI7N2IzcWHO5MciA3pmHYMcbq+0zg3rXzLC4EapNRzlBnQVXuQT4K7klfvcVkZue3l7oi8bS3JlP15XY1LvJXhnTnaOqm8/9XNPnp7fUWerHO0GzrFzfJVIb+rz6LdGvH33nmvWIOVq+VS3pplXw1kfkIczArfl5xKhEKc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730897140; c=relaxed/simple; bh=s/HE862Ebjc4x9QSbLryT2tjzrtXi+x51IAifw3w0tQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=jGDPWqtiie2Wqb4bkDNxc1d9ejoySlBKNxCkxbGD8BtzGfxT4U+iFQYZm91zSFrNkLRfvwkvKNjKOHAjz+Lh++x0npdb9ps9ufv5TklSFmIMQEIFgZssBsUWUfrGeEmTO8+ywEEWmRfr+NMgIELWrphOnIsBJyDHSNHTs1KHtHQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=EP02+HXi; arc=none smtp.client-ip=220.197.31.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="EP02+HXi" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-ID:MIME-Version; bh=0mQMe EqbIH1W/gwL+X7sQKXQSByBBidMVZJPmvHc5LI=; b=EP02+HXiPtv6PJ2JJf9iM dhwANGW36VX8J1WcfU9LF9WabLtDLWh3MSiZX9u7GN3p6gDlB20rv6PH1D5Ha6GI CV8k6CwnROQ6AS2SWK7nOugyhW2K7GmV8TtZG6psrG95wXTFldAHc2zaRXzMzKwn WudKqkRAxVow3sgrejbhhE= Received: from localhost.localdomain (unknown [47.252.33.72]) by gzga-smtp-mtada-g1-0 (Coremail) with SMTP id _____wD3P43DZCtnPigDBA--.6575S2; Wed, 06 Nov 2024 20:44:56 +0800 (CST) From: mrpre To: edumazet@google.com, jakub@cloudflare.com, davem@davemloft.net, dsahern@kernel.org, kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org, bpf@vger.kernel.orgc, linux-kernel@vger.kernel.org Cc: mrpre , Vincent Whitchurch , John Fastabend Subject: [PATCH bpf] bpf: fix recursive lock when verdict program return SK_PASS Date: Wed, 6 Nov 2024 20:44:31 +0800 Message-ID: <20241106124431.5583-1-mrpre@163.com> X-Mailer: git-send-email 2.43.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: _____wD3P43DZCtnPigDBA--.6575S2 X-Coremail-Antispam: 1Uf129KBjvJXoW7KrWkAr1DXF4Duw48JF4fKrg_yoW8Aw1Dpa 4ku3y5GF9rZr18Z3s3KF97Xr1jgw1vgay2gr1ruw1fZrn0gry5urZ5KFy2vF4YvrsrKF98 Zr4jqFsrtw17XaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0piX_-PUUUUU= X-CM-SenderInfo: xpus2vi6rwjhhfrp/1tbiWw2Pp2crYkExlAAAs0 Content-Type: text/plain; charset="utf-8" When the stream_verdict program returns SK_PASS, it places the received skb into its own receive queue, but a recursive lock eventually occurs, leading to an operating system deadlock. This issue has been present since v6.9. ''' sk_psock_strp_data_ready write_lock_bh(&sk->sk_callback_lock) strp_data_ready strp_read_sock read_sock -> tcp_read_sock strp_recv cb.rcv_msg -> sk_psock_strp_read # now stream_verdict return SK_PASS without peer sock assign __SK_PASS =3D sk_psock_map_verd(SK_PASS, NULL) sk_psock_verdict_apply sk_psock_skb_ingress_self sk_psock_skb_ingress_enqueue sk_psock_data_ready read_lock_bh(&sk->sk_callback_lock) <=3D dead lock ''' This topic has been discussed before, but it has not been fixed. Previous discussion: https://lore.kernel.org/all/6684a5864ec86_403d20898@john.notmuch Fixes: 6648e613226e ("bpf, skmsg: Fix NULL pointer dereference in sk_psock_= skb_ingress_enqueue") Reported-by: Vincent Whitchurch Signed-off-by: Jiayuan Chen Signed-off-by: John Fastabend --- net/core/skmsg.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/skmsg.c b/net/core/skmsg.c index b1dcbd3be89e..e90fbab703b2 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -1117,9 +1117,9 @@ static void sk_psock_strp_data_ready(struct sock *sk) if (tls_sw_has_ctx_rx(sk)) { psock->saved_data_ready(sk); } else { - write_lock_bh(&sk->sk_callback_lock); + read_lock_bh(&sk->sk_callback_lock); strp_data_ready(&psock->strp); - write_unlock_bh(&sk->sk_callback_lock); + read_unlock_bh(&sk->sk_callback_lock); } } rcu_read_unlock(); --=20 2.43.5