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 3695E57C700; Wed, 9 Sep 2026 14:16:43 +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=1788963404; cv=none; b=qwixhLpqPFXQgog3/O2t44Ewk7r8me3lmS4+N1o3HE8lsqOijssTBsiKqEKsrcUYGVXxq17n+7ReUpGga2IdR98cpsV1Te3JDs7gGdwXuYcyX8lJQ5SXMioDTFcfpwsCDgpIUisxqg7FKtpHh5mawMiebFPe7+vYVPvyEikIBiM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788963404; c=relaxed/simple; bh=c88ujwx1UEgnncwgCDFrNVLtNPrAk6vA9uMvdyRCLzc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XPyNNYi1bPJmXyt411QCN/3Pj0Y+Ab7pyMzuW6jSR4T6iZjEm+EhQc4zJ5FjMuIgcdXlYbhVrBSjapGJd+0C+gznDPh4kWZqPyjrsCL+AhUGt0MwXGIZ6TmOtYJZvwYbtYGG4Q/dA5XUQytZDsq+l2pClYqmJOxwV/DZiBJaCCQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GASrtS8d; 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="GASrtS8d" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7EFDB1F00A3A; Wed, 9 Sep 2026 14:16:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788963403; bh=JsaPNvl/GZ5h0Yela9cEEaWXBCM2Gi141lI7D2VRnAo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GASrtS8dvr8WxlDJGpt1YB/XnQCUOKYV80VNxJ0TbepbP2xnP7CyJSATg0CIfOdy4 5qVlGgcVSmROR982NchBpkXvQbl5x932g+KJpIsH/LV/XlenZFea4fFfI8gfa79eR7 EcN5oYzuDwfHsHRFEtPiI2rywTtzRPRRCEoY8/ok= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ibrahim Hashimov , Jason Gerecke , Jiri Kosina Subject: [PATCH 6.18 066/583] HID: wacom: validate report length in wacom_intuos_pro2_bt_irq Date: Wed, 9 Sep 2026 15:35:51 +0200 Message-ID: <20260909134240.358032710@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@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: Ibrahim Hashimov commit a8e04f3f894ccb52cfcd7e60125a9f35da4a616d upstream. wacom_intuos_pro2_bt_irq() receives the wire report length in `len` but never consults it before parsing. After the report-id gate it unconditionally calls wacom_intuos_pro2_bt_pen() and then, selected by features.type, a fixed chain of sub-parsers, none of which receive `len`: wacom_intuos_pro2_bt_pen(wacom); if (type == INTUOSP2_BT || type == INTUOSP2S_BT) { wacom_intuos_pro2_bt_touch(wacom); wacom_intuos_pro2_bt_pad(wacom); wacom_intuos_pro2_bt_battery(wacom); } else { wacom_intuos_gen3_bt_pad(wacom); wacom_intuos_gen3_bt_battery(wacom); } Each sub-parser dereferences wacom->data at fixed offsets. The furthest byte touched on each branch is: INTUOSP2_BT / INTUOSP2S_BT: wacom_intuos_pro2_bt_pad() reads data[285] (the touchring byte), so the report must be at least 286 bytes; INTUOSHT3_BT ("gen3"): wacom_intuos_gen3_bt_battery() reads data[45], so the report must be at least 46 bytes. features.type is selected from the VID/PID id_table entry and wacom_setup_device_quirks() force-registers the pen/pad/touch inputs for that type independent of the report descriptor, so a malicious or malfunctioning paired/spoofed Bluetooth peripheral can advertise that VID/PID and send an undersized report that still satisfies the data[0] == 0x80/0x81 gate. The driver then reads past the received report and forwards the bytes to userspace via evdev (MSC_SERIAL / ABS_MISC / ABS_WHEEL on the pen and pad input nodes), an out-of-bounds read with a concrete userspace read-back channel, and a true out-of-bounds read on transports whose backing buffer is sized to the (small) report descriptor rather than a fixed-size staging buffer. This is the same class of bug commit 2f1763f62909 ("HID: wacom: fix out-of-bounds read in wacom_intuos_bt_irq") already hardened in the sibling wacom_intuos_bt_irq(), which guards each report id against its minimum length before parsing. Guard wacom_intuos_pro2_bt_irq() the same way: before parsing, reject reports shorter than the furthest offset the selected branch actually dereferences, warn, and bail out. Because the whole pen/touch/pad/ battery chain runs unconditionally per branch, a single up-front check against the maximum offset (286 bytes for INTUOSP2_BT/INTUOSP2S_BT, 46 bytes for the gen3 branch) bounds every sub-parser. Returning 0 on a short report also skips those calls for the same malformed report, which is the safe, conservative behavior. Fixes: 4922cd26f03c ("HID: wacom: Support 2nd-gen Intuos Pro's Bluetooth classic interface") Cc: stable@vger.kernel.org Signed-off-by: Ibrahim Hashimov Assisted-by: AuditCode-AI:2026.07 Acked-by: Jason Gerecke Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman --- drivers/hid/wacom_wac.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -1548,6 +1548,19 @@ static int wacom_intuos_pro2_bt_irq(stru return 0; } + if (wacom->features.type == INTUOSP2_BT || + wacom->features.type == INTUOSP2S_BT) { + if (len < 286) { + dev_warn(wacom->pen_input->dev.parent, + "Pro2 BT report too short: %zu bytes\n", len); + return 0; + } + } else if (len < 46) { + dev_warn(wacom->pen_input->dev.parent, + "Pro2 BT report too short: %zu bytes\n", len); + return 0; + } + wacom_intuos_pro2_bt_pen(wacom); if (wacom->features.type == INTUOSP2_BT || wacom->features.type == INTUOSP2S_BT) {