From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 DA95C391E57 for ; Fri, 22 May 2026 23:13:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779491610; cv=none; b=gdh4F7drSYF9Y42+MG80iYVjBNS+URmbY3OwkULQvWuWhZz7j/q9PAn0fqkK4OpWrg0vUGpuaduxq4HLkfYmv/yoSYpsbz+i+j9gAb027/QADkcUbLACSSHaWa5nzKrEZ5L/eFBKQbtrwpf8aJzas4GjKo0BZeVwPhG7EOni92Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779491610; c=relaxed/simple; bh=Z7hnlvtj5Ik3uAVwvIVYx6v4ghpCKtw1Ln2dai5pvBA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GmFLmX7tBy7wfwcJE31OERvO4NDJrjEGCj/oI7ZbSH0Sj0gE8u1dEX6O8QxdQu6IIDWIYho7+/nQbipRDNR1QQZIdR8K1wimd7Nsokx9afrbSBP8tmlg04IQHncd4Xc+3O6Q6dWfSNvb2W25aHt1md+SgfkXZmfXLJvErYu7BLM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L0IIt51h; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="L0IIt51h" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 471791F0155C; Fri, 22 May 2026 23:13:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779491608; bh=tP0biwvWC1/s+P3Ason7wOdHO18Zo5vp+Onyw877N74=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=L0IIt51hBpt6xNaQdCBdTzogH3VcfyoAcMBbAvP/sDF64Bp76eatAsHFSTH+rOGyk aVA1fcjs9nQKKuClkg15bzcp0UGXNqoqT2NXzicP1foe9aOE7yusp2AyhaVnZu/jBa 94mMl+736LE8Q0mc8DjFE4wEGAKsbgU30ZAuB3JVkzh/7Qfh/ix5j9XaJCBsAYT8JL CaYn45cT8zPcOy/q1dhETuOv69TGL+rOUIy+5EWxKN1T6Mq/8VrGSOTh2Yc0QWNKxt /oZdWR1H4m6G/Ru7UAPR1KYI1hKogSPm3ZfRZK8HW27/scu8BwcuIZtfH75XoqWJ5O ohKE/EHZUlzRA== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, maxime.chevallier@bootlin.com, danieller@nvidia.com, petrm@nvidia.com, o.rempel@pengutronix.de, idosch@nvidia.com, Jakub Kicinski , andrew@lunn.ch Subject: [PATCH net 8/9] ethtool: cmis: validate start_cmd_payload_size from module Date: Fri, 22 May 2026 16:13:11 -0700 Message-ID: <20260522231312.1710836-9-kuba@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260522231312.1710836-1-kuba@kernel.org> References: <20260522231312.1710836-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The CMIS firmware update code reads start_cmd_payload_size from the module's FW Management Features CDB reply and uses it directly as the byte count for memcpy. The destination buffer is 112 bytes (ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH - 8). So a malicious module (or corrupted response) can cause a OOB write later on in cmis_fw_update_start_download(). Let's error out. If modules that expect longer LPL writes actually exist we should revisit. struct cmis_cdb_start_fw_download_pl's definition has to move, no change there. Fixes: c4f78134d45c ("ethtool: cmis_fw_update: add a layer for supporting firmware update using CDB") Signed-off-by: Jakub Kicinski --- CC: andrew@lunn.ch CC: petrm@nvidia.com CC: danieller@nvidia.com --- net/ethtool/cmis_fw_update.c | 36 ++++++++++++++++++++++-------------- 1 file changed, 22 insertions(+), 14 deletions(-) diff --git a/net/ethtool/cmis_fw_update.c b/net/ethtool/cmis_fw_update.c index df5f344209c4..16190c97e1f7 100644 --- a/net/ethtool/cmis_fw_update.c +++ b/net/ethtool/cmis_fw_update.c @@ -44,6 +44,20 @@ enum cmis_cdb_fw_write_mechanism { CMIS_CDB_FW_WRITE_MECHANISM_BOTH = 0x11, }; +/* See section 9.7.2 "CMD 0101h: Start Firmware Download" in CMIS standard + * revision 5.2. + * struct cmis_cdb_start_fw_download_pl is a structured layout of the + * flat array, ethtool_cmis_cdb_request::payload. + */ +struct cmis_cdb_start_fw_download_pl { + __struct_group(cmis_cdb_start_fw_download_pl_h, head, /* no attrs */, + __be32 image_size; + __be32 resv1; + ); + u8 vendor_data[ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH - + sizeof(struct cmis_cdb_start_fw_download_pl_h)]; +}; + static int cmis_fw_update_fw_mng_features_get(struct ethtool_cmis_cdb *cdb, struct net_device *dev, @@ -86,6 +100,14 @@ cmis_fw_update_fw_mng_features_get(struct ethtool_cmis_cdb *cdb, */ cdb->read_write_len_ext = rpl->read_write_len_ext; fw_mng->start_cmd_payload_size = rpl->start_cmd_payload_size; + if (fw_mng->start_cmd_payload_size > + sizeof_field(struct cmis_cdb_start_fw_download_pl, vendor_data)) { + ethnl_module_fw_flash_ntf_err(dev, ntf_params, + "Start cmd payload size exceeds max LPL payload", + NULL); + return -EINVAL; + } + fw_mng->write_mechanism = rpl->write_mechanism == CMIS_CDB_FW_WRITE_MECHANISM_LPL ? CMIS_CDB_FW_WRITE_MECHANISM_LPL : @@ -97,20 +119,6 @@ cmis_fw_update_fw_mng_features_get(struct ethtool_cmis_cdb *cdb, return 0; } -/* See section 9.7.2 "CMD 0101h: Start Firmware Download" in CMIS standard - * revision 5.2. - * struct cmis_cdb_start_fw_download_pl is a structured layout of the - * flat array, ethtool_cmis_cdb_request::payload. - */ -struct cmis_cdb_start_fw_download_pl { - __struct_group(cmis_cdb_start_fw_download_pl_h, head, /* no attrs */, - __be32 image_size; - __be32 resv1; - ); - u8 vendor_data[ETHTOOL_CMIS_CDB_LPL_MAX_PL_LENGTH - - sizeof(struct cmis_cdb_start_fw_download_pl_h)]; -}; - static int cmis_fw_update_start_download(struct ethtool_cmis_cdb *cdb, struct ethtool_cmis_fw_update_params *fw_update, -- 2.54.0