From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 65EFD27180B; Wed, 12 Feb 2025 14:34:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739370841; cv=none; b=n8gnlZ6ejqRj/K45T70gImacNEr5wfUlqfH9TSnNitJ8CHK70vUMGCSPe98L88hnPEWGukZICn1i1A4tf3SazQVma+DbO4DVZjEjSuU/frnVcztZbOfF3cUB+11ox775MiiAOy+SBowmMrHmEjAdXd7ElHVPF5mgwofeDOIDnQk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739370841; c=relaxed/simple; bh=QgYvjfxo+X0cHfwEov1X2s9rPdFbVkrA5z+AnagMuOI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=kOP8DS7U9nWWrNB1QlgUdW54PFitNl3YzES5Rs9s4O6qHiezhMBjIVJjeEd1CWCRsPw8vtA0YWVYVXK9VQa737qbnr+NG4wbHFwayQ9Pedg8fg8FQ2NuUvEvIIen1dxYZWMQwxArS4h9qzeVX5wlhFaB9w6SiDhR8hlSbkOGOOc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pQs0rJiJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pQs0rJiJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F985C4CEE2; Wed, 12 Feb 2025 14:33:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739370840; bh=QgYvjfxo+X0cHfwEov1X2s9rPdFbVkrA5z+AnagMuOI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=pQs0rJiJgEDjvCI0l0pvtk7cVsUWXVzfgvuDvcYJbfawVHOB8VItrau5u1c2Xfmyw KEloyytS+zW6NNycj2g4xnIIAUPfQSHYxbAjtIX5Pp33ShfIwhkyqkFdDUpfV5pC4z FzlPZ5Y9mkT2dLBAoUYeojbjtaK6sRjgobKdUGJK7i1H0TL9glkuUEu8hf3haEBvd2 KbENN44fThevG4yHP3DiMjg4whfNu9+u4eNzU7OKtFMCwEu0VJcTcAUxcl0HtReQZO XLJi9MgFGZe9mHhwiXsEITD1Mew7oS+GhzUlGYjL0GWWYpfk5aLcwQeQrTzZHxATeW 6U+CVlZwTuB8A== Message-ID: <1ad40918-8b5b-43fb-bd32-66db7825726e@kernel.org> Date: Wed, 12 Feb 2025 14:33:56 +0000 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH bpf-next v4] bpftool: Check map name length when map create To: Rong Tao , andrii@kernel.org, ast@kernel.org Cc: rongtao@cestc.cn, Daniel Borkmann , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , "open list:BPF [TOOLING] (bpftool)" , open list References: From: Quentin Monnet Content-Language: en-GB In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit 2025-02-12 20:45 UTC+0800 ~ Rong Tao > From: Rong Tao > > The size of struct bpf_map::name is BPF_OBJ_NAME_LEN (16). > > bpf(2) { > map_create() { > bpf_obj_name_cpy(map->name, attr->map_name, sizeof(attr->map_name)); > } > } > > When specifying a map name using bpftool map create name, no error is > reported if the name length is greater than 15. > > $ sudo bpftool map create /sys/fs/bpf/12345678901234567890 \ > type array key 4 value 4 entries 5 name 12345678901234567890 > > Users will think that 12345678901234567890 is legal, but this name cannot > be used to index a map. > > $ sudo bpftool map show name 12345678901234567890 > Error: can't parse name > > $ sudo bpftool map show > ... > 1249: array name 123456789012345 flags 0x0 > key 4B value 4B max_entries 5 memlock 304B > > $ sudo bpftool map show name 123456789012345 > 1249: array name 123456789012345 flags 0x0 > key 4B value 4B max_entries 5 memlock 304B > > The map name provided in the command line is truncated, but no warning is > reported. This submission checks the length of the map name. > > Reviewed-by: Quentin Monnet > Signed-off-by: Rong Tao Looks good to me, thank you! Quentin