From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7BDC42DF15B; Tue, 2 Sep 2025 13:41:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756820517; cv=none; b=QB2vo0r1UgZtTBN7CbpY7uOjPzjuSsXmZehdK1bxQ+/w1+Hq1GTcH1M7GHiBMt5rHBnj6EoVqekyjH/dTNairYpcDiBR8UMprPqOOP62FWuHPDEGc3hrU5leHOqvVsjOhljCDG7+tU+Yo12zjD8rxM2hYijrjPfjfLfZBZZ/VtQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756820517; c=relaxed/simple; bh=9EXwtjJVt7hjCEawBaoPzkVk7eyrRjYIuRoVMAhfW+0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oVeE86SDg8eehr+U9vJeGYaw+ZtVkrNJa1zmzTIkCaO8pcru3E7dLrYL4l3nOdzDLJI1VbpDxKdeI/0F12eS2wkDOrq6jXgfOImGFyI/InN+JN9x0iVSwOnMuBgdfKLEfE49POuYpUGanFtUa7DF9BQsOdx+7K7ydJoZSApjujY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FAW+Q/U4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FAW+Q/U4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC62DC4CEED; Tue, 2 Sep 2025 13:41:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756820517; bh=9EXwtjJVt7hjCEawBaoPzkVk7eyrRjYIuRoVMAhfW+0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FAW+Q/U4GpvxwhTHPuMnjUsyiix+M1msKWRfQucg6TEWnRwP9UPnXFXBdvmUKyClA K10EBvKVBbrwKmUmyoiA2RrprOG3PmHYX2LglVkUfBXQRsEXTunC6BDNBaigMFWAAD t+k0raN3M0FV0XHOUoOF5jP4nzhXUcLLfoo/RSFg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qasim Ijaz , Jiri Slaby , Jiri Kosina Subject: [PATCH 6.1 37/50] HID: multitouch: fix slab out-of-bounds access in mt_report_fixup() Date: Tue, 2 Sep 2025 15:21:28 +0200 Message-ID: <20250902131931.995884239@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250902131930.509077918@linuxfoundation.org> References: <20250902131930.509077918@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qasim Ijaz commit 0379eb8691b9c4477da0277ae0832036ca4410b4 upstream. A malicious HID device can trigger a slab out-of-bounds during mt_report_fixup() by passing in report descriptor smaller than 607 bytes. mt_report_fixup() attempts to patch byte offset 607 of the descriptor with 0x25 by first checking if byte offset 607 is 0x15 however it lacks bounds checks to verify if the descriptor is big enough before conducting this check. Fix this bug by ensuring the descriptor size is at least 608 bytes before accessing it. Below is the KASAN splat after the out of bounds access happens: [ 13.671954] ================================================================== [ 13.672667] BUG: KASAN: slab-out-of-bounds in mt_report_fixup+0x103/0x110 [ 13.673297] Read of size 1 at addr ffff888103df39df by task kworker/0:1/10 [ 13.673297] [ 13.673297] CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.15.0-00005-gec5d573d83f4-dirty #3 [ 13.673297] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/04 [ 13.673297] Call Trace: [ 13.673297] [ 13.673297] dump_stack_lvl+0x5f/0x80 [ 13.673297] print_report+0xd1/0x660 [ 13.673297] kasan_report+0xe5/0x120 [ 13.673297] __asan_report_load1_noabort+0x18/0x20 [ 13.673297] mt_report_fixup+0x103/0x110 [ 13.673297] hid_open_report+0x1ef/0x810 [ 13.673297] mt_probe+0x422/0x960 [ 13.673297] hid_device_probe+0x2e2/0x6f0 [ 13.673297] really_probe+0x1c6/0x6b0 [ 13.673297] __driver_probe_device+0x24f/0x310 [ 13.673297] driver_probe_device+0x4e/0x220 [ 13.673297] __device_attach_driver+0x169/0x320 [ 13.673297] bus_for_each_drv+0x11d/0x1b0 [ 13.673297] __device_attach+0x1b8/0x3e0 [ 13.673297] device_initial_probe+0x12/0x20 [ 13.673297] bus_probe_device+0x13d/0x180 [ 13.673297] device_add+0xe3a/0x1670 [ 13.673297] hid_add_device+0x31d/0xa40 [...] Fixes: c8000deb6836 ("HID: multitouch: Add support for GT7868Q") Cc: stable@vger.kernel.org Signed-off-by: Qasim Ijaz Reviewed-by: Jiri Slaby Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman --- drivers/hid/hid-multitouch.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -1448,6 +1448,14 @@ static __u8 *mt_report_fixup(struct hid_ if (hdev->vendor == I2C_VENDOR_ID_GOODIX && (hdev->product == I2C_DEVICE_ID_GOODIX_01E8 || hdev->product == I2C_DEVICE_ID_GOODIX_01E9)) { + if (*size < 608) { + dev_info( + &hdev->dev, + "GT7868Q fixup: report descriptor is only %u bytes, skipping\n", + *size); + return rdesc; + } + if (rdesc[607] == 0x15) { rdesc[607] = 0x25; dev_info(