From patchwork Sat Nov 23 23:54:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Foster Snowhill X-Patchwork-Id: 13883981 Received: from pv50p00im-ztdg10012001.me.com (pv50p00im-ztdg10012001.me.com [17.58.6.51]) (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 0886D19F113 for ; Sat, 23 Nov 2024 23:55:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406114; cv=none; b=YnTcD7lkoanz11PRBnUik5LCaLWK8va8C1atBcw4jwkLO+GA+oyx/Gn56v6BYzcoAUVaa/PtM5i1cxGnBTwZvMXP5Y1RlPb4pyyK5GegslffQ1ZUGCDWp75ad1SoRnQWo5Bv2/L1Ti/tpk0o4v9uQGARqBuJ3aVobyJNFCkjrgY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406114; c=relaxed/simple; bh=qTz05nqTnzWGlitAN8pjkwivXOcYrp4rWS/0ISUDs1s=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=SW9Eky8Z6udRz0uwhT2UgZp8EYUD1T6E9eaWvrNV0Dg5H1sayJ5evjy2QKCus50Vl+rRAEUJazio03MH9puvG+1JXgBkpRE6UjtDrDd+FUdtsMkdmARfeZuKthNhgiBGT18r4y77g5vhuCwD8SC6uuIR/4P8wuUIHS+1bmQY8CU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy; spf=pass smtp.mailfrom=pen.gy; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b=PBOM+HoE; arc=none smtp.client-ip=17.58.6.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pen.gy Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b="PBOM+HoE" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pen.gy; s=sig1; t=1732406112; bh=ZejMZ0Ds6cRN9zJCVFToCfAynKBCNZqnISZujY3tuU0=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=PBOM+HoE/sa8NVr0t2S5ZapVXUsG1rbNxc+6y7xk3jZXgKo8vkgUB8+UgWzU4ri3+ hdIeTSjdJX5F5Auv57umcWsPP+GtIc84aAFqwHPBxkkcJ2J/coavFHrdUM1D8MUqkF NZ5HM+gPCT/y1lh8SX9RILYFiJdPybp/gmH8guiqaQzQnBs81AlstWlzJDEcZdNSYZ 4s0i1DhjDUWX+jX4LLSfTIc25iOTORhE0sPPKNsn3JLPe/0A7EK34O54Yp7R8GeOAY zDVRJnbTCFJ6x8Je7h7apYImUs7/xND5D7NkhICcDw0+78+mSgQTK6fWhbFiQCD/8F pwri/L/sPzpmg== Received: from fossa.se1.pen.gy (pv50p00im-dlb-asmtp-mailmevip.me.com [17.56.9.10]) by pv50p00im-ztdg10012001.me.com (Postfix) with ESMTPSA id 22848A0139; Sat, 23 Nov 2024 23:55:07 +0000 (UTC) From: Foster Snowhill To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Georgi Valkov , Simon Horman , Oliver Neukum , netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: [PATCH net v3 1/6] usbnet: ipheth: break up NCM header size computation Date: Sun, 24 Nov 2024 00:54:27 +0100 Message-ID: <20241123235432.821220-1-forst@pen.gy> X-Mailer: git-send-email 2.45.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: Pz9GJTxeu-MoO2r4pgHdbXUE0VvDHwZO X-Proofpoint-ORIG-GUID: Pz9GJTxeu-MoO2r4pgHdbXUE0VvDHwZO X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-11-23_19,2024-11-21_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 mlxlogscore=373 malwarescore=0 clxscore=1030 spamscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2411230200 Originally, the total NCM header size was computed as the sum of two vaguely labelled constants. While accurate, it's not particularly clear where they're coming from. Use sizes of existing NCM structs where available. Define the total NDP16 size based on the maximum amount of DPEs that can fit into the iOS-specific fixed-size header. Fixes: a2d274c62e44 ("usbnet: ipheth: add CDC NCM support") Signed-off-by: Foster Snowhill --- Each individual patch in the v3 series tested with iPhone 15 Pro Max, iOS 18.1.1: compiled cleanly, ran iperf3 between phone and computer, observed no errors in either kernel log or interface statistics. v3: * NDP16 header size is computed from max DPE count constant, not the other way around. * Split out from a monolithic patch in v2. v2: https://lore.kernel.org/netdev/20240912211817.1707844-1-forst@pen.gy/ No code changes. Update commit message to further clarify that `ipheth` is not and does not aim to be a complete or spec-compliant CDC NCM implementation. v1: https://lore.kernel.org/netdev/20240907230108.978355-1-forst@pen.gy/ --- drivers/net/usb/ipheth.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 46afb95ffabe..2084b940b4ea 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -61,7 +61,18 @@ #define IPHETH_USBINTF_PROTO 1 #define IPHETH_IP_ALIGN 2 /* padding at front of URB */ -#define IPHETH_NCM_HEADER_SIZE (12 + 96) /* NCMH + NCM0 */ +/* On iOS devices, NCM headers in RX have a fixed size regardless of DPE count: + * - NTH16 (NCMH): 12 bytes, as per CDC NCM 1.0 spec + * - NDP16 (NCM0): 96 bytes, of which + * - NDP16 fixed header: 8 bytes + * - maximum of 22 DPEs (21 datagrams + trailer), 4 bytes each + */ +#define IPHETH_NDP16_MAX_DPE 22 +#define IPHETH_NDP16_HEADER_SIZE (sizeof(struct usb_cdc_ncm_ndp16) + \ + IPHETH_NDP16_MAX_DPE * \ + sizeof(struct usb_cdc_ncm_dpe16)) +#define IPHETH_NCM_HEADER_SIZE (sizeof(struct usb_cdc_ncm_nth16) + \ + IPHETH_NDP16_HEADER_SIZE) #define IPHETH_TX_BUF_SIZE ETH_FRAME_LEN #define IPHETH_RX_BUF_SIZE_LEGACY (IPHETH_IP_ALIGN + ETH_FRAME_LEN) #define IPHETH_RX_BUF_SIZE_NCM 65536 From patchwork Sat Nov 23 23:54:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Foster Snowhill X-Patchwork-Id: 13883982 Received: from pv50p00im-ztdg10012001.me.com (pv50p00im-ztdg10012001.me.com [17.58.6.51]) (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 111E21A38E3 for ; Sat, 23 Nov 2024 23:55:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406125; cv=none; b=TVAIBjersMqgditWrTFh9llUi5ErXs89wM/u9Cr74mzfDrO5vveUPI6PWrl0Raqlz8qlSSRkNjqr+kH6K+9j5U5+EPDe8Aoy+u4ABPTcQ6fqU/Ld0zcwbQnon2y1NfIqlpccM6f271sTABBNw5+3cK7g3pZCLhrOA+f2YehyeF8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406125; c=relaxed/simple; bh=+IuoLCtpU9LEpq2qS4rg4AoNn6INUTDGShMb/r5V1VU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=H3mXvU5DwK0952A8qYd/p6R6eq/Sdv4EtldzEQ51CPZiAYIXeqBWkjYH75DyjKcBSVTzhp4cqqcDTvXgwlC6ceznjlB6KAHazdMUH5E8RExhbvy/dO1DjzeMPsYE90qHbwPPgCASnHm6KBXm9CxEjhUUzsVWd8rEKnl1OAoowaU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy; spf=pass smtp.mailfrom=pen.gy; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b=VN10dnr+; arc=none smtp.client-ip=17.58.6.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pen.gy Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b="VN10dnr+" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pen.gy; s=sig1; t=1732406122; bh=8XGc+JFhBXvZG8lFIOrG5sLkIVFMKa9quSy8yU//xtw=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=VN10dnr+vQyy9lHaq/d4vUadT4rapQt1+BU9L78T84tKp8+2PVBM2Snz+8XxOpbgY 1tE8HZ7gIZ++EMM+jpd61Bytgzd+ecKMPn3Eyfs1bPFKu5Z41rnP2juREA9Fa97myL JU+dxWEuDpTBYXvyL+XS9xbwEWSafMCQ0OxPi3zyJLc6Nz/e2611h+E0IIuKY629Bp iA7/ZmBLDROKDbdBY5/kG35UlOfOZu91jueFF3DQ+QBYmQo0rXsuON69dnMgJ16+2w b5X76H/sEqqUC3t74pMjTMgUi+ca+IGM5SsBE5oYMyLCGGsh90EqyRUrQ2CGzf+Ywj /K3LsojAniwcQ== Received: from fossa.se1.pen.gy (pv50p00im-dlb-asmtp-mailmevip.me.com [17.56.9.10]) by pv50p00im-ztdg10012001.me.com (Postfix) with ESMTPSA id 05560A0139; Sat, 23 Nov 2024 23:55:17 +0000 (UTC) From: Foster Snowhill To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Georgi Valkov , Simon Horman , Oliver Neukum , netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: [PATCH net v3 2/6] usbnet: ipheth: fix possible overflow in DPE length check Date: Sun, 24 Nov 2024 00:54:28 +0100 Message-ID: <20241123235432.821220-2-forst@pen.gy> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20241123235432.821220-1-forst@pen.gy> References: <20241123235432.821220-1-forst@pen.gy> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: eiC_qm0aNVjK1upq75MBbx5lPlM6MX4K X-Proofpoint-ORIG-GUID: eiC_qm0aNVjK1upq75MBbx5lPlM6MX4K X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-11-23_19,2024-11-21_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 mlxlogscore=670 malwarescore=0 clxscore=1030 spamscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2411230200 Originally, it was possible for the DPE length check to overflow if wDatagramIndex + wDatagramLength > U16_MAX. This could lead to an OoB read. Move the wDatagramIndex term to the other side of the inequality. An existing condition ensures that wDatagramIndex < urb->actual_length. Fixes: a2d274c62e44 ("usbnet: ipheth: add CDC NCM support") Signed-off-by: Foster Snowhill --- v3: Split out from a monolithic patch in v2 as an atomic change. v2: https://lore.kernel.org/netdev/20240912211817.1707844-1-forst@pen.gy/ No code changes. Update commit message to further clarify that `ipheth` is not and does not aim to be a complete or spec-compliant CDC NCM implementation. v1: https://lore.kernel.org/netdev/20240907230108.978355-1-forst@pen.gy/ --- drivers/net/usb/ipheth.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 2084b940b4ea..4b590a5269fd 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -254,8 +254,8 @@ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) while (le16_to_cpu(dpe->wDatagramIndex) != 0 && le16_to_cpu(dpe->wDatagramLength) != 0) { if (le16_to_cpu(dpe->wDatagramIndex) >= urb->actual_length || - le16_to_cpu(dpe->wDatagramIndex) + - le16_to_cpu(dpe->wDatagramLength) > urb->actual_length) { + le16_to_cpu(dpe->wDatagramLength) > urb->actual_length - + le16_to_cpu(dpe->wDatagramIndex)) { dev->net->stats.rx_length_errors++; return retval; } From patchwork Sat Nov 23 23:54:29 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Foster Snowhill X-Patchwork-Id: 13883983 Received: from pv50p00im-ztdg10012001.me.com (pv50p00im-ztdg10012001.me.com [17.58.6.51]) (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 1D2141A76CC for ; Sat, 23 Nov 2024 23:55:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406129; cv=none; b=Fty8vjoZ+PFZj4WgtJwaEtMXH8jb9tEH1jARvtJfXiCW5gGFgo0AMiD3bYki3y1DAODeDgZwQglI0tDjxWo5aDryTQqGCl+1WFg2cvAnm7NBjrBcsiQ8lPVMwlrL1k86XTlAVVaVkPuirEhiJjEEadNwiaiTXaMzz8DiLUPquDU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406129; c=relaxed/simple; bh=1HzHn8mPky2y7uM1dLkqc3wa/hd6LwgPbDLZVE5ggOo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qiWgZhbB5jXfUeacdcwvXs8OqzYTi+yQbEHNUhSzosR/9Ewl03cEk8BQcEDHOMwgJSdY+pKhaYME1pMEl9c2FlXRt9e9J7Kja3l75rKnz+P4UZCZALGWKkG3E3tNDnKBtJNmj73t6XvN4M/QNVgLxdlVPxVucrdnvG6+KYMVgms= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy; spf=pass smtp.mailfrom=pen.gy; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b=Fi2oAJKJ; arc=none smtp.client-ip=17.58.6.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pen.gy Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b="Fi2oAJKJ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pen.gy; s=sig1; t=1732406127; bh=MpSWz+5ERIrifCs4KMNySygiKsVPGa3ccAhJpp7M/ps=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=Fi2oAJKJWVbTx8eZ5H37gMQik93kRg4raMYtshct8WSimBnIqE+BQNINJRO9sIWUF 7oS7mSn29iOg2IqHZim2A8fuII5o0lQxwwYmeIH2VzH1cHowW33uklP8O1DX3/nABy jI6HFsvipnxY8OIcb5j5AqEbG8ag5uuzAuJnFQWon48wxT9lImVNlreeYgYGkg0aWK 7O0whjfb/EOUF3GuJvDVQzED9UBDTdHTkvJDlmAXRCukfnbS5X8K4zu0e4cBZ9uYL5 9pRC0b4q1fRSDKjDXnK+MYAaIVdpnGyppMQ9ITvdOt5HRt2h6Kz3s34b07ftKUc+IG keO2/iYBJi5Sg== Received: from fossa.se1.pen.gy (pv50p00im-dlb-asmtp-mailmevip.me.com [17.56.9.10]) by pv50p00im-ztdg10012001.me.com (Postfix) with ESMTPSA id 596B0A0175; Sat, 23 Nov 2024 23:55:22 +0000 (UTC) From: Foster Snowhill To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Georgi Valkov , Simon Horman , Oliver Neukum , netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: [PATCH net v3 3/6] usbnet: ipheth: check that DPE points past NCM header Date: Sun, 24 Nov 2024 00:54:29 +0100 Message-ID: <20241123235432.821220-3-forst@pen.gy> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20241123235432.821220-1-forst@pen.gy> References: <20241123235432.821220-1-forst@pen.gy> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: m-uMfCjaxZBRV6aylzxpaEfnAa8h-LFz X-Proofpoint-ORIG-GUID: m-uMfCjaxZBRV6aylzxpaEfnAa8h-LFz X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-11-23_19,2024-11-21_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 mlxlogscore=481 malwarescore=0 clxscore=1030 spamscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2411230200 By definition, a DPE points at the start of a network frame/datagram. Thus it makes no sense for it to point at anything that's part of the NCM header. It is not a security issue, but merely an indication of a malformed DPE. Enforce that all DPEs point at the data portion of the URB, past the NCM header. Fixes: a2d274c62e44 ("usbnet: ipheth: add CDC NCM support") Signed-off-by: Foster Snowhill --- v3: Split out from a monolithic patch in v2 as an atomic change. v2: https://lore.kernel.org/netdev/20240912211817.1707844-1-forst@pen.gy/ No code changes. Update commit message to further clarify that `ipheth` is not and does not aim to be a complete or spec-compliant CDC NCM implementation. v1: https://lore.kernel.org/netdev/20240907230108.978355-1-forst@pen.gy/ --- drivers/net/usb/ipheth.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 4b590a5269fd..48c79e69bb7b 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -253,7 +253,8 @@ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) dpe = ncm0->dpe16; while (le16_to_cpu(dpe->wDatagramIndex) != 0 && le16_to_cpu(dpe->wDatagramLength) != 0) { - if (le16_to_cpu(dpe->wDatagramIndex) >= urb->actual_length || + if (le16_to_cpu(dpe->wDatagramIndex) < IPHETH_NCM_HEADER_SIZE || + le16_to_cpu(dpe->wDatagramIndex) >= urb->actual_length || le16_to_cpu(dpe->wDatagramLength) > urb->actual_length - le16_to_cpu(dpe->wDatagramIndex)) { dev->net->stats.rx_length_errors++; From patchwork Sat Nov 23 23:54:30 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Foster Snowhill X-Patchwork-Id: 13883984 Received: from pv50p00im-ztdg10012001.me.com (pv50p00im-ztdg10012001.me.com [17.58.6.51]) (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 D938C1ABEA1 for ; Sat, 23 Nov 2024 23:55:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406135; cv=none; b=acOIZYxU9FHbxXz5QdHCXYyKdvlIsnAgBZlyUQrZPErFv566XlijC/PdRr5qjhVbpSH2ziqte+jygbRuSX1WRcH7bXkRp4k/WiiC47FdyGxsQmh1OovjYNX6D6uajvKxGUdogK6dOlX5R97LKrHIjG0XUP/C8mjadz5XCMSwH2o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406135; c=relaxed/simple; bh=/c/T2n02Jza0P2IpNMrW20I5Ahg5Ww4mKJyItH+JWXU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JQ0mAIP1pWCYuo8fWg2tIbET0N38/D9cqtKpKRuSCjBk05SEeRRHjuYp5MRWrkAzRbH8AvW7G7sVX/MwehmIUWMeFykrhtDkMNQ8M/g9Enj9NN5D5I6Fr4Z/4/dpQDb/Bxfz1s7I3D+QRuF8L1iaXzyvBB0EI0/ZlyY2VHz57Y8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy; spf=pass smtp.mailfrom=pen.gy; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b=GsMGn05x; arc=none smtp.client-ip=17.58.6.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pen.gy Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b="GsMGn05x" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pen.gy; s=sig1; t=1732406132; bh=NuPwDG3I3id9LvvDEZwalmCEDEPYz7UUsfKG/NaauWY=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=GsMGn05xQJCQNVszaJEp+dNQeGwu17ZIUcpK6hmmHcBspWp3zxjuaCPf6SsqXy7/J vsjUPBhWokCxAxOOWUXxgS3k1srwFIpjBbkY2dZAnf4LAJNaMR7xYRAPR5pviQyE6J kro6OsazRptxDR1NP0yitf+pfxKmO21vz4A4E9NoZESjgdH3lGrs/L+fRlcfAqP2o9 5gGEsncCJ9E78UoeEwFEUxBkzt6ZpQFNNmXYlLw0y7RLOUm3qMvmDo3YJAcYvIwkvt tVgL78lLmbFDHStz1eg1cHYJ576v2Pl7/bgG0RRzSe9KN9tv++IKgTHFS3ap1bzuqa kqoCcmXq0cJ6w== Received: from fossa.se1.pen.gy (pv50p00im-dlb-asmtp-mailmevip.me.com [17.56.9.10]) by pv50p00im-ztdg10012001.me.com (Postfix) with ESMTPSA id 47592A01D5; Sat, 23 Nov 2024 23:55:27 +0000 (UTC) From: Foster Snowhill To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Georgi Valkov , Simon Horman , Oliver Neukum , netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: [PATCH net v3 4/6] usbnet: ipheth: use static NDP16 location in URB Date: Sun, 24 Nov 2024 00:54:30 +0100 Message-ID: <20241123235432.821220-4-forst@pen.gy> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20241123235432.821220-1-forst@pen.gy> References: <20241123235432.821220-1-forst@pen.gy> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: FRIZSRD39wQz7kYVc_zx5ostTj_KTMYd X-Proofpoint-ORIG-GUID: FRIZSRD39wQz7kYVc_zx5ostTj_KTMYd X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-11-23_19,2024-11-21_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 mlxlogscore=548 malwarescore=0 clxscore=1030 spamscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2411230200 Original code allowed for the start of NDP16 to be anywhere within the URB based on the `wNdpIndex` value in NTH16. Only the start position of NDP16 was checked, so it was possible for even the fixed-length part of NDP16 to extend past the end of URB, leading to an out-of-bounds read. On iOS devices, the NDP16 header always directly follows NTH16. Rely on and check for this specific format. This, along with NCM-specific minimal URB length check that already exists, will ensure that the fixed-length part of NDP16 plus a set amount of DPEs fit within the URB. Note that this commit alone does not fully address the OoB read. The limit on the amount of DPEs needs to be enforced separately. Fixes: a2d274c62e44 ("usbnet: ipheth: add CDC NCM support") Signed-off-by: Foster Snowhill --- v3: Split out from a monolithic patch in v2 as an atomic change. v2: https://lore.kernel.org/netdev/20240912211817.1707844-1-forst@pen.gy/ No code changes. Update commit message to further clarify that `ipheth` is not and does not aim to be a complete or spec-compliant CDC NCM implementation. v1: https://lore.kernel.org/netdev/20240907230108.978355-1-forst@pen.gy/ --- drivers/net/usb/ipheth.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 48c79e69bb7b..3f9ea6546720 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -236,16 +236,14 @@ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) } ncmh = urb->transfer_buffer; - if (ncmh->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN) || - le16_to_cpu(ncmh->wNdpIndex) >= urb->actual_length) { + if (ncmh->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) { dev->net->stats.rx_errors++; return retval; } - ncm0 = urb->transfer_buffer + le16_to_cpu(ncmh->wNdpIndex); - if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN) || - le16_to_cpu(ncmh->wHeaderLength) + le16_to_cpu(ncm0->wLength) >= - urb->actual_length) { + /* On iOS, NDP16 directly follows NTH16 */ + ncm0 = urb->transfer_buffer + sizeof(struct usb_cdc_ncm_nth16); + if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) { dev->net->stats.rx_errors++; return retval; } From patchwork Sat Nov 23 23:54:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Foster Snowhill X-Patchwork-Id: 13883985 Received: from pv50p00im-ztdg10012001.me.com (pv50p00im-ztdg10012001.me.com [17.58.6.51]) (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 837021ABEA1 for ; Sat, 23 Nov 2024 23:55:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406140; cv=none; b=BFj1mnVbKMTT1UEjxqjmZ+X180T+NLyyu4X0X/oNjz6HSD2oAjm4ov4WMghkk/ewYprnXzVgkoy7iDkp7YUbszmPHNC9uZGUrKu5oQG6zRpAKgYFJgnEsjsMb2E+2UlEP1nhAOZHdysXP6P1jciW/iP3y0zU500xrPb6hs3w7x4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732406140; c=relaxed/simple; bh=mSKgNv+8pEY9lOW+d989YvSCydnI59nBODLjbYnN1uc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oRJMVlAnFZ07zc74fF5xfeqvHtO4UpbVFuRPFjNiXPvOkbzeYSk5pHuFp5fvf/ysAv7hfmx9AbDJHXQhe/3BoJ4vFyWH+LmJQPtyCt1bkzf+rvgPcbZTUWHbfy/2trjP8yNQBRInwznpCMo3LJsmzAW6PPa8E+VKS3e5wmStDJg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy; spf=pass smtp.mailfrom=pen.gy; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b=JbJodhNX; arc=none smtp.client-ip=17.58.6.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=pen.gy Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pen.gy Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pen.gy header.i=@pen.gy header.b="JbJodhNX" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pen.gy; s=sig1; t=1732406137; bh=NCS0BS66uf7Asgthxy+WGil5SatQ+cnWgHoOGK0eBeY=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=JbJodhNXraoXEngwxXM7ASHn1EXDfQsVrHos4K/sn9iuZmuoSE4QRiSGQrN22taq0 3HY/PFdYT5PCXLT7bsX5XUcDKGNr1DmqEdwhj3hF0yQfZeAEpfE6XRluGHI/R4LHBc nh8wFVxBdsReXUe2Lti4IfaCIjfp+NXeJE+xX8JnSI6WQZ+2rsAJ4NKoFOGcOJIf9f UwBz01xGpVIZwn3jJhqeqm12urcfI3D25Kfxww+AeaDFADGAylfjYzsDhaEomFkl/8 wVJgL2ieucf+KWRjLaPQMA5Yd/0b3soWecLjGffI+5B1ONFKZjktyE+mOwEYGI9qN3 oJ8Wjf2JzUsZQ== Received: from fossa.se1.pen.gy (pv50p00im-dlb-asmtp-mailmevip.me.com [17.56.9.10]) by pv50p00im-ztdg10012001.me.com (Postfix) with ESMTPSA id 25801A006F; Sat, 23 Nov 2024 23:55:32 +0000 (UTC) From: Foster Snowhill To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Georgi Valkov , Simon Horman , Oliver Neukum , netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: [PATCH net v3 5/6] usbnet: ipheth: refactor NCM datagram loop, fix DPE OoB read Date: Sun, 24 Nov 2024 00:54:31 +0100 Message-ID: <20241123235432.821220-5-forst@pen.gy> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20241123235432.821220-1-forst@pen.gy> References: <20241123235432.821220-1-forst@pen.gy> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: twy898kQTSRr558DFtDHPKr2za0R4I2r X-Proofpoint-ORIG-GUID: twy898kQTSRr558DFtDHPKr2za0R4I2r X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-11-23_19,2024-11-21_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 mlxlogscore=741 malwarescore=0 clxscore=1030 spamscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2411230200 Introduce an rx_error label to reduce repetitions in the header signature checks. Store wDatagramIndex and wDatagramLength after endianness conversion to avoid repeated le16_to_cpu() calls. Rewrite the loop to return on a null trailing DPE, which is required by the CDC NCM spec. In case it is missing, fall through to rx_error. Fix an out-of-bounds DPE read, limit the number of processed DPEs to the amount that fits into the fixed-size NDP16 header. Fixes: a2d274c62e44 ("usbnet: ipheth: add CDC NCM support") Signed-off-by: Foster Snowhill --- v3: Split out from a monolithic patch in v2 as an atomic change. v2: https://lore.kernel.org/netdev/20240912211817.1707844-1-forst@pen.gy/ No code changes. Update commit message to further clarify that `ipheth` is not and does not aim to be a complete or spec-compliant CDC NCM implementation. v1: https://lore.kernel.org/netdev/20240907230108.978355-1-forst@pen.gy/ --- drivers/net/usb/ipheth.c | 44 +++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 21 deletions(-) diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 3f9ea6546720..122557b5e5a9 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -224,9 +224,9 @@ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) struct usb_cdc_ncm_ndp16 *ncm0; struct usb_cdc_ncm_dpe16 *dpe; struct ipheth_device *dev; + u16 dg_idx, dg_len; int retval = -EINVAL; char *buf; - int len; dev = urb->context; @@ -236,40 +236,42 @@ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) } ncmh = urb->transfer_buffer; - if (ncmh->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) { - dev->net->stats.rx_errors++; - return retval; - } + if (ncmh->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) + goto rx_error; /* On iOS, NDP16 directly follows NTH16 */ ncm0 = urb->transfer_buffer + sizeof(struct usb_cdc_ncm_nth16); - if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) { - dev->net->stats.rx_errors++; - return retval; - } + if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) + goto rx_error; dpe = ncm0->dpe16; - while (le16_to_cpu(dpe->wDatagramIndex) != 0 && - le16_to_cpu(dpe->wDatagramLength) != 0) { - if (le16_to_cpu(dpe->wDatagramIndex) < IPHETH_NCM_HEADER_SIZE || - le16_to_cpu(dpe->wDatagramIndex) >= urb->actual_length || - le16_to_cpu(dpe->wDatagramLength) > urb->actual_length - - le16_to_cpu(dpe->wDatagramIndex)) { + for (int dpe_i = 0; dpe_i < IPHETH_NDP16_MAX_DPE; ++dpe_i, ++dpe) { + dg_idx = le16_to_cpu(dpe->wDatagramIndex); + dg_len = le16_to_cpu(dpe->wDatagramLength); + + /* Null DPE must be present after last datagram pointer entry + * (3.3.1 USB CDC NCM spec v1.0) + */ + if (dg_idx == 0 && dg_len == 0) + return 0; + + if (dg_idx < IPHETH_NCM_HEADER_SIZE || + dg_idx >= urb->actual_length || + dg_len > urb->actual_length - dg_idx) { dev->net->stats.rx_length_errors++; return retval; } - buf = urb->transfer_buffer + le16_to_cpu(dpe->wDatagramIndex); - len = le16_to_cpu(dpe->wDatagramLength); + buf = urb->transfer_buffer + dg_idx; - retval = ipheth_consume_skb(buf, len, dev); + retval = ipheth_consume_skb(buf, dg_len, dev); if (retval != 0) return retval; - - dpe++; } - return 0; +rx_error: + dev->net->stats.rx_errors++; + return retval; } static void ipheth_rcvbulk_callback(struct urb *urb) From patchwork Sat Nov 23 23:54:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Foster Snowhill X-Patchwork-Id: 13883986 Received: from pv50p00im-ztdg10012001.me.com (pv50p00im-ztdg10012001.me.com [17.58.6.51]) (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 8DF9F1AB517 for ; Sat, 23 Nov 2024 23:55:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=17.58.6.51 ARC-Seal: i=1; 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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: Georgi Valkov , Simon Horman , Oliver Neukum , netdev@vger.kernel.org, linux-usb@vger.kernel.org Subject: [PATCH net v3 6/6] usbnet: ipheth: document scope of NCM implementation Date: Sun, 24 Nov 2024 00:54:32 +0100 Message-ID: <20241123235432.821220-6-forst@pen.gy> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20241123235432.821220-1-forst@pen.gy> References: <20241123235432.821220-1-forst@pen.gy> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Proofpoint-GUID: 6Ni2wP-kL7_kiiZ8VNi83iHAvl3uEL17 X-Proofpoint-ORIG-GUID: 6Ni2wP-kL7_kiiZ8VNi83iHAvl3uEL17 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-11-23_19,2024-11-21_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 bulkscore=0 suspectscore=0 mlxlogscore=925 malwarescore=0 clxscore=1030 spamscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2308100000 definitions=main-2411230200 Clarify that the "NCM" implementation in `ipheth` is very limited, as iOS devices aren't compatible with the CDC NCM specification in regular tethering mode. For a standards-compliant implementation, one shall turn to the `cdc_ncm` module. Signed-off-by: Foster Snowhill --- v3: This comment was part of the commit message for v2. With v3, given how the patches are split up, it makes more sense to add the comment directly in code. v2: https://lore.kernel.org/netdev/20240912211817.1707844-1-forst@pen.gy/ No code changes. Update commit message to further clarify that `ipheth` is not and does not aim to be a complete or spec-compliant CDC NCM implementation. v1: n/a --- drivers/net/usb/ipheth.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c index 122557b5e5a9..e906ec4b7969 100644 --- a/drivers/net/usb/ipheth.c +++ b/drivers/net/usb/ipheth.c @@ -218,6 +218,14 @@ static int ipheth_rcvbulk_callback_legacy(struct urb *urb) return ipheth_consume_skb(buf, len, dev); } +/* In "NCM mode", the iOS device encapsulates RX (phone->computer) traffic + * in NCM Transfer Blocks (similarly to CDC NCM). However, unlike reverse + * tethering (handled by the `cdc_ncm` driver), regular tethering is not + * compliant with the CDC NCM spec, as the device is missing the necessary + * descriptors, and TX (computer->phone) traffic is not encapsulated + * at all. Thus `ipheth` implements a very limited subset of the spec with + * the sole purpose of parsing RX URBs. + */ static int ipheth_rcvbulk_callback_ncm(struct urb *urb) { struct usb_cdc_ncm_nth16 *ncmh;