From patchwork Sat Nov 9 15:03:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiayuan Chen X-Patchwork-Id: 13869664 X-Patchwork-Delegate: bpf@iogearbox.net Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.2]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 890691946A4; Sat, 9 Nov 2024 15:05:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.2 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731164721; cv=none; b=OsNAdbWGMxU/X5At4OslzPXlnHxNLWVweXVTx3tIOVGdnAM1fxRNTZ4IkGAim/bpH9dnyyqGVN5AkY+fR+VK+c+6AWXJBYB3NgmppRuT42ChS+klchuwWC9f6Gr3sNFVfS+12gBHpQ3Jsn1hb22mSDxw+56dS272VnI4+cILAJA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731164721; c=relaxed/simple; bh=s/HE862Ebjc4x9QSbLryT2tjzrtXi+x51IAifw3w0tQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TF2ZYEcm5I35aTVyjVIVlXIf89vZjhiZXMfyjTTVFha54gDW6QjCWnPb2Wevu333FMWrXV16/3YXYezQbxE2SwxKRx6Sbkvp9SdB4CTl6fjS9FKFgjXT3I6RIAGe2TQYVEqLXs9UuTwjJlG61hJKJ3JPI/Ukf2thnipN+qZ0zW8= 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=NN+u/TW8; arc=none smtp.client-ip=220.197.31.2 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="NN+u/TW8" 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=NN+u/TW8ioIIC5LkpoM8j bh7KVHuYGtfHirZboAFQEdVfG20egBLydDKbfd4kFMm6FRBG9NG8vX4xHjw2h4J5 wP95q5qwPfhbKML8O7an/FvyeYbNxRgKxDfeGV4UTCeNQvJAZ613fOU19+C7WcXM rF9hf983qkrro4dsQvqPE0= Received: from localhost.localdomain (unknown [47.252.33.72]) by gzga-smtp-mtada-g0-4 (Coremail) with SMTP id _____wBnT4exeS9n3Jk_GA--.36911S3; Sat, 09 Nov 2024 23:03:29 +0800 (CST) From: Jiayuan Chen To: martin.lau@linux.dev, 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.org, linux-kernel@vger.kernel.org, horms@kernel.org, daniel@iogearbox.net Cc: Jiayuan Chen , Vincent Whitchurch , John Fastabend Subject: [PATCH bpf v2 1/2] bpf: fix recursive lock when verdict program return SK_PASS Date: Sat, 9 Nov 2024 23:03:04 +0800 Message-ID: <20241109150305.141759-2-mrpre@163.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20241109150305.141759-1-mrpre@163.com> References: <20241109150305.141759-1-mrpre@163.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: _____wBnT4exeS9n3Jk_GA--.36911S3 X-Coremail-Antispam: 1Uf129KBjvJXoW7KrWkAr1DXF4Duw48JF4fKrg_yoW8Aw1Dpa 4ku3y5GF9rZr18Z3s3KF97Xr1jgw1vgay2gr1ruw1fZrn0gry5urZ5KFy2vF4YvrsrKF98 Zr4jqFsrtw17XaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0piU3vUUUUUU= X-CM-SenderInfo: xpus2vi6rwjhhfrp/1tbiDweSp2cvca9g6AAAsj X-Patchwork-Delegate: bpf@iogearbox.net 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 = 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) <= 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();