From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f45.google.com (mail-dl1-f45.google.com [74.125.82.45]) (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 44D0533987E for ; Sat, 14 Mar 2026 17:51:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.45 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773510712; cv=none; b=cUnnpp9fiFRoHt8DEBlRZPMQbLS/iexawQMuOQdWHTMWl6T6Gv1MQmAMsEG+2CUjnOVA3f2m63Bbxj/2A4U12EzSM1BFikcoBJEcDTx60Bhzmiv/BZUnkIwym3hz65TOxkku3s39QBinIZ30QmCCU6wDfDsZHCJ8f1CEQFiJjzA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773510712; c=relaxed/simple; bh=uItdHPzM8/YhmEnZVDdGZfkeDxlbuzv/yCC5R1HveNc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WruHcS/dxaXZlmCBccoT70uI0SuVu78RPhQrpI05CnkHLZai1ZLVxtYfh2KAXWEa176Srxfvp8K+nUQ89Zev6uInIZRir1FF1x726X0pPY9LBTlsBOKJlbBZOHw07BHlDrg/WNDLMtJbH/tQY93enFo5LlH7dyn1+o79dGwyWiU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=herbertland.com; spf=pass smtp.mailfrom=herbertland.com; dkim=pass (2048-bit key) header.d=herbertland.com header.i=@herbertland.com header.b=hdIc7rvJ; arc=none smtp.client-ip=74.125.82.45 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=herbertland.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=herbertland.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=herbertland.com header.i=@herbertland.com header.b="hdIc7rvJ" Received: by mail-dl1-f45.google.com with SMTP id a92af1059eb24-1273349c56bso4827482c88.0 for ; Sat, 14 Mar 2026 10:51:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=herbertland.com; s=google; t=1773510710; x=1774115510; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=A6arbcjbT27jtKab9iAQCIQYW6MTuFeHR9L7LFxRYIY=; b=hdIc7rvJdGSMWdd4TmsVsxU+JfJDlTR6oEEyWq8z4S0k7H+LLqy+FtKL592a5MLBXi Eluscw6cRIBi8eWMhXwZX0is7v3Bh/3zZFx6rCmp8vvnF0ElpQ+VYeAv9czJDf01QOIw gXH6eBD9D9WcXrcfkp921xOuRKPWL4yT5wXY2EKMUKaWemoGHs7MiRNJgrI9Va5UjpQS HcNxQLpSfSv8xNERl10dFN2cWK5TZpr9YoaVJ3MIqwJjxx7xOcKqAqudrMnG7iYHP/sV DcOpiUoBKBmbfFGnCTagC3XNk9SJPA01SIfi1IHZ7xajAYImnGTZjeoyNCkOYCiwzgtI 5Trw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1773510710; x=1774115510; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=A6arbcjbT27jtKab9iAQCIQYW6MTuFeHR9L7LFxRYIY=; b=s4KiRpYtYDuV2IDNHE29aWSQXophZvAs66gCITefK8GOA3UzsB2wgzzqSrjVh4QCh2 0LVRoTAgLv9iohOlTZ1o+YMbmhg8usfwabHb8HX0AHPrX4gY3cz3M1J1gjEKvYPpKNT0 W/iekiCUou/pNUO841E6SPTuzKncMLYPdfgiuXODyvS73JtaTeNL39TJjq8J8qA0MccQ hXTd4jnNEv3dYBXlcDV3AliJmJu09ftVKAm+xJ0sWkCxppCLSAFq8QiquUv2HRU6r6Zf 0qURucLdIpPNFdhAZavMAsFd00rOz/ESrVGVBmcO1+YU7WnGq9KkNNvmMfZO20Rl5o3c JDUg== X-Forwarded-Encrypted: i=1; AJvYcCUejh8QOy9plwWceE5uH75Qdn/7mYnLa+Ds06xYNuvKnaIx2gDPOzvgN60C0XSzOxeGXzHXhiU=@vger.kernel.org X-Gm-Message-State: AOJu0YxB9jeGeT4irYdc7Lahf1n7vysOAgAibPOUn22TVMIVmADnMLTj sy7Fk9j9YGs+DTMIrbM//VFyjCH4b//VBWmRMqksPZFmegZK2MbXFB1W0TQfp0NlNQ== X-Gm-Gg: ATEYQzyI3mRPUbSnMzma09jVT5enPYw4SSoV5Ge95N0vafRWgJE8Zo6cjirfpMtQgal XJhFHozJ+YQrwglQkbQi10miuZ6mN78CDBsZS1iauhlcuHD4jVNX5pDuWCLq1R/mYkj5Rzf6/N1 Mhaq0nA6Ys/pPqDnVhenncKBzO2QVAO2AZxJ/Rm2fxFwj6DOPLI1dpssZCjm2E88d9Z6v1TCLza siNuATklLvABJawybIS3CyWNOGHErCyx3gURBgr+iyqRY5aPsy9Ql6NgvsxdJgcSDh6XgE/m6c7 qIHoedtZ/P62CCcxAVGezelKqu3A1DyZwmjCM3AFzm4cyJrmHHe0lpc2UamPq5dqqqXC5glvzqP QflLhs/u4kBqN8icNd3jbF3pOxKiYFq446hEsIzCm8hiTNUY6Uc9DgMvrZTOeQTXqzVJHAMGqbc l7+wXnJddO7rqxtd65h0tcNHlpOizCn2Fq5evCqU7HPMESXisnQzz49UNM97OQOHfZt6xBmQ== X-Received: by 2002:a05:7022:f97:b0:128:ce44:be8b with SMTP id a92af1059eb24-128f3dd1398mr3270442c88.25.1773510710284; Sat, 14 Mar 2026 10:51:50 -0700 (PDT) Received: from pong.herbertland.com ([2601:646:8980:b330:eb38:94c4:209f:a764]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-128f6384f6csm5917206c88.9.2026.03.14.10.51.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 14 Mar 2026 10:51:49 -0700 (PDT) From: Tom Herbert To: davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, justin.iurman@uliege.be, willemdebruijn.kernel@gmail.com, pabeni@redhat.com Cc: Tom Herbert , Justin Iurman Subject: [PATCH net-next v9 05/10] ipv6: Document defaults for max_{dst|hbh}_opts_number sysctls Date: Sat, 14 Mar 2026 10:51:19 -0700 Message-ID: <20260314175124.47010-6-tom@herbertland.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260314175124.47010-1-tom@herbertland.com> References: <20260314175124.47010-1-tom@herbertland.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In the descriptions of max_dst_opts_number and max_hbh_opts_number sysctls add text about how a zero setting means that a packet with any Destination or Hop-by-Hop options is dropped. Report the defaults for max_dst_opts_number and max_hbh_opts_number are 2 which means up to two options may be accepted. Signed-off-by: Tom Herbert Reviewed-by: Justin Iurman --- Documentation/networking/ip-sysctl.rst | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 2e3a746fcc6d..453643c70c8d 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -2511,19 +2511,25 @@ mld_qrv - INTEGER max_dst_opts_number - INTEGER Maximum number of non-padding TLVs allowed in a Destination - options extension header. If this value is less than zero - then unknown options are disallowed and the number of known - TLVs allowed is the absolute value of this number. + options extension header. If this value is zero then receive + Destination Options processing is disabled in which case packets + with the Destination Options extension header are dropped. If + this value is less than zero then unknown options are disallowed + and the number of known TLVs allowed is the absolute value of + this number. - Default: 8 + Default: 2 max_hbh_opts_number - INTEGER Maximum number of non-padding TLVs allowed in a Hop-by-Hop - options extension header. If this value is less than zero - then unknown options are disallowed and the number of known - TLVs allowed is the absolute value of this number. + options extension header. If this value is zero then receive + Hop-by-Hop Options processing is disabled in which case packets + with the Hop-by-Hop Options extension header are dropped. + If this value is less than zero then unknown options are disallowed + and the number of known TLVs allowed is the absolute value of this + number. - Default: 8 + Default: 2 max_dst_opts_length - INTEGER Maximum length allowed for a Destination options extension -- 2.43.0