From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-177.mta1.migadu.com (out-177.mta1.migadu.com [95.215.58.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AD36F38C40E for ; Thu, 11 Jun 2026 11:48:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781178489; cv=none; b=Y10Q7/Piy+kPdn84Ml7e7xv6FzxWADvH03UCybN5QQTiRnqOakuvG6SfxYillAW5MEEVWhx1TKBOqVc/d7k6uj9OqNv7sYoUVOKoq/geNkJuhH7npPcD50iDoD7Y97+HK4PBhcAPR/bAiiVzTTkXezQxOTP2+sO0rz4oLUudkf0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781178489; c=relaxed/simple; bh=XoJJqz/Vzlhe5uQ13vjg3VCYz0+nnya2oNA5rEu2MFI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=EyMrvMThX5Afpp/BAZ89ibduaVe88fDweSCq85pb5eleKrOYeJk4z2cB/IR5LY+U+5YpNF7kdSoHWmNsoy3tcYzO99dEVk/E/pwvl1bWHaOZ+gsMBg8s5sDke+rjcz8WX6FiSaefTxg7uOCF1oYXUAfpxgmiR76E58uL44aafsc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=RORblfg7; arc=none smtp.client-ip=95.215.58.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="RORblfg7" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1781178475; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KQnWBNAsCzAJ3HZFLh8gKD/BTcTn+ZltOUCQYwic1XA=; b=RORblfg7meoiuNtp/4rapSWxIbyQ3GSD56k+VHAHqBL8MYQlHZlZ8AwsPmqEN/U1lUg5xC 2TkMpkl7U1+iTVWyuEPZSZNb6SJAm00yHNu1vXY1DlG/NXb3xMs4wKQHraPF7QMXm8y1S3 pxg1RJ3/urOmVLrfdS3obkRRcKbX5Hs= Date: Thu, 11 Jun 2026 19:47:32 +0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net v3] tcp: clear sock_ops cb flags before force-closing a child socket To: Sechang Lim , Eric Dumazet , Neal Cardwell , "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Kuniyuki Iwashima , Simon Horman , Lawrence Brakmo , Alexei Starovoitov , Jiayuan Chen , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org References: <20260611092923.1895982-1-rhkrqnwk98@gmail.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Jiayuan Chen In-Reply-To: <20260611092923.1895982-1-rhkrqnwk98@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 6/11/26 5:29 PM, Sechang Lim wrote: > A child socket inherits the listener's bpf_sock_ops_cb_flags via > sk_clone_lock(). If its setup fails in tcp_v4_syn_recv_sock() / > tcp_v6_syn_recv_sock(), the child is freed through put_and_exit, where > inet_csk_prepare_forced_close() drops the socket lock and tcp_done() runs > without it. > > If BPF_SOCK_OPS_STATE_CB_FLAG was inherited, tcp_done() -> tcp_set_state() > calls tcp_call_bpf(), which expects the lock and trips sock_owned_by_me(): > > WARNING: include/net/sock.h:1799 at tcp_set_state+0x433/0x550 > RIP: 0010:tcp_set_state+0x433/0x550 include/net/sock.h:1799 > Call Trace: > > tcp_done+0xba/0x250 net/ipv4/tcp.c:5095 > tcp_v4_syn_recv_sock+0x850/0xa50 net/ipv4/tcp_ipv4.c:1787 > tcp_check_req+0xf30/0x1360 net/ipv4/tcp_minisocks.c:926 > tcp_v4_rcv+0x1047/0x1b50 net/ipv4/tcp_ipv4.c:2164 > > > The child is freed before it is ever established, so it should run no > sock_ops callback. Clear its cb flags in inet_csk_prepare_for_destroy_sock(), > the common point for the IPv4, IPv6 and chtls forced-close paths and for the > MPTCP ->syn_recv_sock() failure path (dispose_child), which reaches tcp_done() > on a child that was never established too. > > Suggested-by: Jiayuan Chen > Fixes: d44874910a26 ("bpf: Add BPF_SOCK_OPS_STATE_CB") > Signed-off-by: Sechang Lim Reviewed-by: Jiayuan Chen