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 74BE124DD17 for ; Tue, 25 Aug 2026 11:03:33 +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=1787655817; cv=none; b=IU2hs77tnNZqi/rVcqcCuEjrm0Ao/+N8MWRLPCKQKPWB/mXKCxv1yyZhAUkXaoOj6onFL5X6ld5axN9akyJj+mc7x3OSDAb5D+ijLEtr5gQFJCMkAiOPevQKm8AiAMiFtSz78uimsXKuYikMVpy1JtzrIV5NJto8qKMdYRHQ3KA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787655817; c=relaxed/simple; bh=pL376zGnHrYuIt+0muFXJFSkGv/Qykxnrnn/jN2sojg=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=XObbHR5UOPE1TOGKj9VVq1ufL/zde/NxOXkD6mklg9Vn0agfpyLgQlVTX7V68DU5iElc4I/f8vXCs3W626tMKXrswfcpcmoNyt+ayX73HhyrtR0uRnOCkSk7fMs66o4pctdvTrbEvi7EL5aK572CqZcUtxdHWAclTheTdOvAXLU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TQ86aL5p; 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="TQ86aL5p" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56D571F000E9; Tue, 25 Aug 2026 11:03:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787655812; bh=wvLz8QnDyoXKpMtW1KCcISBDryeH5KTM0Ziq5qFVJac=; h=Subject:To:Cc:From:Date; b=TQ86aL5plmv1KHQZBEY6d7GYbQOgRErIhQ0IeMwVL4m/ytWveWUqPRa8IfZF1k2/M iqvUXD+XetNl0tvV5U3j4SVwblWIuLA6Zn/uWNCxqoo5fmvLOYwHw+c3/vZrn12cQC ZRrLoxeRQL1ItHfOp6uKV7YnaAA1Y44hRDNLtWFM= Subject: FAILED: patch "[PATCH] HID: pidff: fix OOB write when hid->inputs is empty" failed to apply to 6.6-stable tree To: baul.lee@xbow.com,federico.kirschbaum@xbow.com,jkosina@suse.com Cc: From: Date: Tue, 25 Aug 2026 13:03:18 +0200 Message-ID: <2026082518-countless-imply-6af9@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 67bb1074e3d2d12fa059a9cc707e89398a4e4704 # git commit -s git send-email --to '' --in-reply-to '2026082518-countless-imply-6af9@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 67bb1074e3d2d12fa059a9cc707e89398a4e4704 Mon Sep 17 00:00:00 2001 From: Baul Lee Date: Sun, 26 Jul 2026 15:25:03 +0900 Subject: [PATCH] HID: pidff: fix OOB write when hid->inputs is empty hid_pidff_init_with_quirks() derives its input_dev from list_entry(hid->inputs.next, struct hid_input, list) without first checking that hid->inputs is non-empty. The list member of struct hid_input is at offset 0, so on an empty list list_entry() yields &hid->inputs itself and the following hidinput->input load reads an unrelated member of struct hid_device. dev is then a type-confused pointer, and force-feedback init writes through it: each set_bit(FF_*, dev->ffbit) stores 8 bytes at dev + 192, past the end of the object dev actually aliases, and input_ff_create() adds further writes of a heap pointer and two function pointers. Until hid-universal-pidff the only caller was hid_pidff_init() from usbhid, which runs under HID_CLAIMED_INPUT and therefore always has at least one hid_input. universal_pidff_probe() starts the device with HID_CONNECT_DEFAULT & ~HID_CONNECT_FF and then calls hid_pidff_init_with_quirks() directly whenever the descriptor carries a PID usage page, bypassing that gate. A report descriptor whose only application collection is on HID_UP_PID leaves hid->inputs empty while hid_connect() still succeeds through the hidraw claim, so probe reaches the unguarded list_entry(). The write happens in the USB probe path, on the hotplug workqueue, so plugging in a malicious device is enough to trigger it; no attacker software and no logged-in user are required. KASAN reports an 8-byte out-of-bounds write in hid_pidff_init_with_quirks() reached from universal_pidff_probe(). Check for an empty list before deriving dev and return -ENODEV, as the other HID force-feedback drivers already do. universal_pidff_probe() propagates the error and unwinds. Discovered by XBOW, triaged by Baul Lee Fixes: f06bf8d94fff ("HID: Add hid-universal-pidff driver and supported device ids") Reported-by: Federico Kirschbaum Reported-by: Baul Lee Cc: stable@vger.kernel.org Signed-off-by: Baul Lee Signed-off-by: Jiri Kosina diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c index 5f4395f7c645..22951b7ecd17 100644 --- a/drivers/hid/usbhid/hid-pidff.c +++ b/drivers/hid/usbhid/hid-pidff.c @@ -1539,13 +1539,20 @@ static int pidff_check_autocenter(struct pidff_device *pidff, int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks) { struct pidff_device *pidff; - struct hid_input *hidinput = - list_entry(hid->inputs.next, struct hid_input, list); - struct input_dev *dev = hidinput->input; + struct hid_input *hidinput; + struct input_dev *dev; struct ff_device *ff; int max_effects; int error; + if (list_empty(&hid->inputs)) { + hid_err(hid, "no inputs found\n"); + return -ENODEV; + } + + hidinput = list_first_entry(&hid->inputs, struct hid_input, list); + dev = hidinput->input; + hid_dbg(hid, "starting pid init\n"); if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {