From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f181.google.com (mail-pg1-f181.google.com [209.85.215.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1FBAE7CF39; Tue, 19 Mar 2024 09:42:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710841368; cv=none; b=hZNJAM7C3WxdaGFwLwge8ECdyTy4Ihivzo9PzJsmoaqPNPh2gwB1TU4Sz8SF8B5NOF31cZuFwmn8trVwxVyjng8DgMd7GqSFDsfQFhtVQ3bdiAxd2kXmVq0KE+L92esA4h3U4eWI05IJWVzGzdMSfCXJfi9a7I4j5nJ582jQfkg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710841368; c=relaxed/simple; bh=VoxZ0wAIPgZvjeJVvx3sbrLqugtTMSD6fOtPdH0GOP0=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=Zr8cVZmH4oTIfihWuD1IgqQ79RerKQiTPx+2zDvwRbbJhz22pPcpQLKX566a6BdEM0LtRcV2Ptwn7RAOwU8VGTjrkai2dijTtCACRJE+3dHV2qZUYdLw8c57pPAHjhdPEUnKUw26ab81Urii0Z3vFtYjRNMQo3NIyl/xFyMhxyk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=YbFqela/; arc=none smtp.client-ip=209.85.215.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YbFqela/" Received: by mail-pg1-f181.google.com with SMTP id 41be03b00d2f7-5cdbc42f5efso152087a12.0; Tue, 19 Mar 2024 02:42:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1710841366; x=1711446166; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=h3Jc7JexdJWOSk6A5zgkFucGWbxIC8CCsVzJZltost0=; b=YbFqela/BcYU+SFSwJbsO0TWOI+WnM2LZLcqWALh1FWwI+fEATd18n91DXCpZoPu5+ KDevyjAi4CxC9q3cOxaNQkZsn9isrmX6SW7AxoCmNuMN55dFgkRJWcKxqsaK/4pTPW0/ i7+RpoguAlNiC+Olv9jk/q+x2FoBOFhBQCTxlJlnbiWoUZYsaCj0Wol0w5M+RG3B+0Cu y4SInra0tjAUG56lalpinbCe8b1RMHb9bN8f4pwDkWGQ3qY0WlKmSW/YvkoRtFpy9KTy CaE6geJvuvIA3AadFs6hC+aLPX0Z/2bk+72Lew/0g5BxRrcuOANdssnCLDeekMngajrm q6Lg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1710841366; x=1711446166; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=h3Jc7JexdJWOSk6A5zgkFucGWbxIC8CCsVzJZltost0=; b=SU9AIkZyqUhTXNdf1m45owMg/mWxg2lmuggF1bD4EqTCfu1zTz1IqGbv8Urn2OpGIX U3IdsjX01qmbZfsSEHk3utNE7rPEllog2TIrA9tMMsp9S7rOTs10If/QpIuLbw0uoKN/ QudUFEzI89kQE6oM3kZ9JlN0RN5C+RJ7vdPqzrgptn5tI3g79whObff1Af/8pMXX1B3U V5erRP1DWDcW0RZ1O59EajrCaOx4BRzhVOm6+34dV+xlBfQXe6oVMBe19b2vJd/m8Frf qKOlMPMhChJN+eSALbjTHPtkq0wzdK6seOkB809gQFkFpaamyQJn6Nk8faaQnYnOtSQL r9Ig== X-Forwarded-Encrypted: i=1; AJvYcCUQNJzG81O7080O8vBAog8mniv2j+PT5iKx3tPWsCiX0lFMSr8/TTJXuCNxRrdCM8xF0cXAR4FHvopV7i61XJenrg/AXi6c X-Gm-Message-State: AOJu0YyuVnEQf6qe7ryhoRlQHoJTI2R/2BPZA+qgdN/OgdlFXhKbsNCb m08v+Ydjzyj5EcV3MortD48Wmx7d0nKG2OYrwZyxlWy5YIDZbtbFtXaWwsmkBcQTTUDLffSVzqS tV8zUSYmdECQENNQxVRPFCfqlxPA= X-Google-Smtp-Source: AGHT+IGc/LLvA9JX6rB7zk19QS3UES3qWoQ1gM/EyNWJ9NfQ7ECIeml/JglEJv8Y/Tz5bUhkWVPcWAbT7RuWFBudizs= X-Received: by 2002:a17:90a:2ecb:b0:29c:75de:bd04 with SMTP id h11-20020a17090a2ecb00b0029c75debd04mr10377073pjs.3.1710841366279; Tue, 19 Mar 2024 02:42:46 -0700 (PDT) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20240311122401.6549-1-lizheng043@gmail.com> <20240311135117.GA1244788@maili.marvell.com> In-Reply-To: From: James Lee Date: Tue, 19 Mar 2024 17:42:34 +0800 Message-ID: Subject: Re: [EXTERNAL] Re: [PATCH] neighbour: guarantee the localhost connections be established successfully even the ARP table is full To: Ratheesh Kannoth Cc: "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , "nhorman@tuxdriver.com" , "davem@davemloft.net" , "jmorris@namei.org" , "James.Z.Li@dell.com" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable It's not an issue, the loopback device can only be created by kernel itself, loopback neigh entry also can only be created by kernel, one loopback neigh for ipv4 ,one for ipv6, impossible that the num of loopback neigh entries exceeds 2. Ratheesh Kannoth =E4=BA=8E2024=E5=B9=B43=E6=9C=8818= =E6=97=A5=E5=91=A8=E4=B8=80 23:36=E5=86=99=E9=81=93=EF=BC=9A > > > From: James Lee > > Sent: Monday, March 18, 2024 2:09 PM > > To: Ratheesh Kannoth > > Cc: linux-kernel@vger.kernel.org; netdev@vger.kernel.org; > > nhorman@tuxdriver.com; davem@davemloft.net; jmorris@namei.org; > > James.Z.Li@dell.com > > Subject: [EXTERNAL] Re: [PATCH] neighbour: guarantee the localhost > > connections be established successfully even the ARP table is full > > > > Prioritize security for external emails: Confirm sender and content saf= ety > > before clicking links or opening attachments > > > > ---------------------------------------------------------------------- > > loopback neigh is a special device in the neighbour system which is use= d by all > > local communications and state is NUD_NOARP. > > Any setting value of gc_thresh3 might encounter arp table be full, manu= ally > > increasing gc_thresh3 can resolve this issue for every time, but we hop= e this > > issue automatically be resolved in Linux kernel for all local communica= tions > > whenever ARP table is full, rather than manually operation as a workaro= und. > > Issue is , these are dynamic entries which cannot be removed by gc. And = there is no > Threshold applicable on it. I feel like, this may be exploited. >