From patchwork Tue Aug 10 09:28:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Iwashima, Kuniyuki" X-Patchwork-Id: 12428441 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E30DC4338F for ; Tue, 10 Aug 2021 09:29:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A34560EE9 for ; Tue, 10 Aug 2021 09:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238989AbhHJJ3Y (ORCPT ); Tue, 10 Aug 2021 05:29:24 -0400 Received: from smtp-fw-6001.amazon.com ([52.95.48.154]:45477 "EHLO smtp-fw-6001.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239041AbhHJJ3X (ORCPT ); Tue, 10 Aug 2021 05:29:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.co.jp; i=@amazon.co.jp; q=dns/txt; s=amazon201209; t=1628587743; x=1660123743; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=sZsQpW+Xl4bDqxL6EClTQGWl1FTe1Lq6AgjjgeiW8EE=; b=ZeQlZ/ho8rBbYNHuM9NQycN70zLPzTR7E6FL/IingvnP6aX5DjwNWW8i hB8XpcyjzITuAJb4sQEBXOEAUvVYDtrpXHuR1AiSdUEHQy8hFsV8Hrhsw kwikjQmji2SbMFFAmgHdjEh6QxZrtvpZJxW65kM+0ZsYGF8ohjCxgkDLW U=; X-IronPort-AV: E=Sophos;i="5.84,310,1620691200"; d="scan'208";a="132824593" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-1d-e69428c4.us-east-1.amazon.com) ([10.43.8.6]) by smtp-border-fw-6001.iad6.amazon.com with ESMTP; 10 Aug 2021 09:29:02 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan3.iad.amazon.com [10.40.159.166]) by email-inbound-relay-1d-e69428c4.us-east-1.amazon.com (Postfix) with ESMTPS id 3FD8DC0C4D; Tue, 10 Aug 2021 09:28:57 +0000 (UTC) Received: from EX13D04ANC001.ant.amazon.com (10.43.157.89) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:28:57 +0000 Received: from 88665a182662.ant.amazon.com (10.43.160.189) by EX13D04ANC001.ant.amazon.com (10.43.157.89) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:28:52 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , "Song Liu" , Yonghong Song , John Fastabend , KP Singh CC: Benjamin Herrenschmidt , Kuniyuki Iwashima , Kuniyuki Iwashima , , Subject: [PATCH v4 bpf-next 2/3] bpf: Support "%c" in bpf_bprintf_prepare(). Date: Tue, 10 Aug 2021 18:28:06 +0900 Message-ID: <20210810092807.13190-3-kuniyu@amazon.co.jp> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210810092807.13190-1-kuniyu@amazon.co.jp> References: <20210810092807.13190-1-kuniyu@amazon.co.jp> MIME-Version: 1.0 X-Originating-IP: [10.43.160.189] X-ClientProxiedBy: EX13D08UWC001.ant.amazon.com (10.43.162.110) To EX13D04ANC001.ant.amazon.com (10.43.157.89) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net /proc/net/unix uses "%c" to print a single-byte character to escape '\0' in the name of the abstract UNIX domain socket. The following selftest uses it, so this patch adds support for "%c". Note that it does not support wide character ("%lc" and "%llc") for simplicity. Signed-off-by: Kuniyuki Iwashima Acked-by: Yonghong Song --- kernel/bpf/helpers.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 15746f779fe1..6d3aaf94e9ac 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -907,6 +907,20 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, tmp_buf += err; num_spec++; + continue; + } else if (fmt[i] == 'c') { + if (!tmp_buf) + goto nocopy_fmt; + + if (tmp_buf_end == tmp_buf) { + err = -ENOSPC; + goto out; + } + + *tmp_buf = raw_args[num_spec]; + tmp_buf++; + num_spec++; + continue; }