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 1928D2E7373; Sun, 7 Jun 2026 10:13:44 +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=1780827225; cv=none; b=tmVxk2+YyfglFvObFN9aJscq41/RgNBlZAjgHJolYVA4fh9XWbePNzg5guMi/Vx/d+xxzECg7E0X64CtPpeAMytFaRTzsRrvrUUEX7egMHt8/D7u2mzFWQ8MYKoklIw1Ep0fN10Lt2+hYTkSMCw+LKsx0dJFCj5uWX5HJ0C2XXI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780827225; c=relaxed/simple; bh=EwX2S1LgFczWGXm/teEpYuHKGoF6SyVtpjOhF8Gb76c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DGROp9a5GnZzDwX5rDt0D1ypR0kqPwbO5TCsmROzrw7RWJ8TmOiyMZpArgnXgqfVgjppx8ybGlvmiB8JBJrZ9C1//0U/rPOtKa04pXiKg0NEGYhW7/YKougmLNjEuTEfefo3mDMt4ounaGO8KpGt6a51cLYc4oL1EPc8yGerRXI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MDQ4tiqK; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="MDQ4tiqK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5DF871F00893; Sun, 7 Jun 2026 10:13:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780827224; bh=fNKVBwrUKbE+n+2n+DjKEyp0RykrdN5R9xV49n6JYwA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=MDQ4tiqKt7vBEEJegY6lgoSf7ktO1elZlrMvH3epSzXyaBrnZQJe7KsAthrUxMyqW 3AVtR1TjwuUpDmXTjiZqVLcfXu4rP0y1dWQ3Sll9NQpO2xELuboBqCVkBzVDwXoKiC s5a0VK/S7NzUQyKQiozHjzJysgZAy6Ff+NMJfCrg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Maxime Chevallier , Danielle Ratson , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 051/315] ethtool: cmis: validate start_cmd_payload_size from module Date: Sun, 7 Jun 2026 11:57:18 +0200 Message-ID: <20260607095729.469454606@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095727.528828913@linuxfoundation.org> References: <20260607095727.528828913@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jakub Kicinski [ Upstream commit 12c2496a71f82f63617971ca9b730dffa05cf58b ] 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") Reviewed-by: Maxime Chevallier Reviewed-by: Danielle Ratson Link: https://patch.msgid.link/20260522231312.1710836-9-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- 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 df5f344209c47b..16190c97e1f78c 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, -- 2.53.0