From patchwork Wed Dec 18 05:34:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiayuan Chen X-Patchwork-Id: 13913059 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.4]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 98830143C72; Wed, 18 Dec 2024 05:35:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.4 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734500148; cv=none; b=k41I7wzQuemAxM1bLfyZgLfIQGIGuiHIG/vGk2sYIGn5ELI5qzOkEVP6PU4UcKdcuBoaGU74keWPFRYelgxvpEtBbNiw2fDWMgY/tENvG+qkKAmVQPWxU7Mu+29Rvs8WlSnvkixJtDJ0UW3AtoOYnsjyfScd5UIwTBtVzlqyqgE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734500148; c=relaxed/simple; bh=tOv70svTsw5JyE7ZRJMqQry+EwpddJvzh9JBA924Ws0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=dptVNyvq9Cc4sfGgglbzowOxtv/RcOo0JVsrHUNRg36cslRqLUXfa1pi4jzW8cRXXznYCaonAa43j8UlTOIT7fPa8LpEO/1RwDnWqYBPu+Ryqe6aPq6aMMIusH3ePHNa23fzlb715TmNBmOn+ClVcI+ctodTscoyeTJGQTC5jwo= 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=kSaLxwd7; arc=none smtp.client-ip=220.197.31.4 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="kSaLxwd7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-ID:MIME-Version; bh=K4Dtg rKG1R64fHEoii+RKwFL3H1AcpX+UCf6j3HNLBo=; b=kSaLxwd7HaFGlnoaV4hY6 kIyoL4s3WErZznBym/y770iBYiANLpbYXPiT+s9+WWOyWClyugUM51jSYaIqZcdr v3buBs0Zya+PaW2v9QqPFqBySgCAEdovKDO9kuQRimxl4bse/Qq/+qhcQdb/bgi6 4CBtGpHD/lcDbjTDHi6cLU= Received: from localhost.localdomain (unknown []) by gzga-smtp-mtada-g1-2 (Coremail) with SMTP id _____wDXf3juXmJn1VZZBQ--.30577S2; Wed, 18 Dec 2024 13:34:46 +0800 (CST) From: Jiayuan Chen To: bpf@vger.kernel.org Cc: martin.lau@linux.dev, ast@kernel.org, edumazet@google.com, jakub@cloudflare.com, davem@davemloft.net, dsahern@kernel.org, kuba@kernel.org, pabeni@redhat.com, linux-kernel@vger.kernel.org, song@kernel.org, john.fastabend@gmail.com, andrii@kernel.org, mhal@rbox.co, yonghong.song@linux.dev, daniel@iogearbox.net, xiyou.wangcong@gmail.com, horms@kernel.org, Jiayuan Chen Subject: [PATCH bpf v3 0/2] bpf: fix wrong copied_seq calculation and add tests Date: Wed, 18 Dec 2024 13:34:06 +0800 Message-ID: <20241218053408.437295-1-mrpre@163.com> X-Mailer: git-send-email 2.43.5 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: _____wDXf3juXmJn1VZZBQ--.30577S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxWFyrGFyfXw4kuryDAFyxKrg_yoW5CFyxpF WkC3yFgrnrtFWIvFnrAayIqF4rGw4rCay5Jr1rXay3Zr4UKr93Zrn7KF43Zr95GrW5ZF15 Zr15Xrs09w1DZa7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0ziYFAPUUUUU= X-CM-SenderInfo: xpus2vi6rwjhhfrp/1tbiWw25p2diVznI9QABsf X-Patchwork-Delegate: bpf@iogearbox.net A previous commit described in this topic http://lore.kernel.org/bpf/20230523025618.113937-9-john.fastabend@gmail.com directly updated 'sk->copied_seq' in the tcp_eat_skb() function when the action of a BPF program was SK_REDIRECT. For other actions, like SK_PASS, the update logic for 'sk->copied_seq' was moved to tcp_bpf_recvmsg_parser() to ensure the accuracy of the 'fionread' feature. That commit works for a single stream_verdict scenario, as it also modified 'sk_data_ready->sk_psock_verdict_data_ready->tcp_read_skb' to remove updating 'sk->copied_seq'. However, for programs where both stream_parser and stream_verdict are active(strparser purpose), tcp_read_sock() was used instead of tcp_read_skb() (sk_data_ready->strp_data_ready->tcp_read_sock) tcp_read_sock() now still update 'sk->copied_seq', leading to duplicated updates. In summary, for strparser + SK_PASS, copied_seq is redundantly calculated in both tcp_read_sock() and tcp_bpf_recvmsg_parser(). The issue causes incorrect copied_seq calculations, which prevent correct data reads from the recv() interface in user-land. Modifying tcp_read_sock() or strparser implementation directly is unreasonable, as it is widely used in other modules. Here, we introduce a method tcp_bpf_read_sock() to replace 'sk->sk_socket->ops->read_sock' (like 'tls_build_proto()' does in tls_main.c). Such replacement action was also used in updating tcp_bpf_prots in tcp_bpf.c, so it's not weird. (Note that checkpatch.pl may complain missing 'const' qualifier when we define the bpf-specified 'proto_ops', but we have to do because we need update it). Also we remove strparser check in tcp_eat_skb() since we implement custom function tcp_bpf_read_sock() without copied_seq updating. Since strparser currently supports only TCP, it's sufficient for 'ops' to inherit inet_stream_ops. We added test cases for bpf + strparser and separated them from sockmap_basic. This is because we need to add more test cases for strparser in the future. Fixes: e5c6de5fa025 ("bpf, sockmap: Incorrectly handling copied_seq") --- v2-v3: save skb data offset for ENOMEM. (John Fastabend) https://lore.kernel.org/bpf/20241209152740.281125-1-mrpre@163.com/#r v1-v2: fix patchwork fail by adding Fixes tag --- Jiayuan Chen (2): bpf: fix wrong copied_seq calculation selftests/bpf: add strparser test for bpf include/linux/skmsg.h | 2 + include/net/tcp.h | 1 + net/core/skmsg.c | 3 + net/ipv4/tcp.c | 2 +- net/ipv4/tcp_bpf.c | 108 +++++- .../selftests/bpf/prog_tests/sockmap_basic.c | 53 --- .../selftests/bpf/prog_tests/sockmap_strp.c | 344 ++++++++++++++++++ .../selftests/bpf/progs/test_sockmap_strp.c | 51 +++ 8 files changed, 507 insertions(+), 57 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/sockmap_strp.c create mode 100644 tools/testing/selftests/bpf/progs/test_sockmap_strp.c base-commit: 5a6ea7022ff4d2a65ae328619c586d6a8909b48b