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 79E0E2BCF7F; Tue, 25 Aug 2026 13:31:51 +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=1787664713; cv=none; b=Mgo1hEzuTzrxmMCjCb6NWUotcez1Y682gyLm8j2Goj/Iq49/uwPeMAJikF28Ns0qz66LUJDwgZQsi72AtWUhHMG3dC04sdoN2XIxp39N9Fz8bfXJn5iZGCm9D5vkRWzEKSpRU4tPrbV3pZ835NUMumhp0EGrxDF+gAquPsn5BtI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787664713; c=relaxed/simple; bh=mpI0rJK+Kw9MLUGPzLpeFcxn4A+bnjyTKNTQMH3AJHI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lEhMLWGaLib5po2QOvYzQA35784BfReiVGQwp20grBCY9PAYgFBXLpwjkQRjchQAjCly9ZduuKxHxTKzTLs644HWMaXo6GhwGhF4cApXjdOKKn9SSYphF3v/GVgYIObgL36qj10CTFynxKYTXkM4l7tPStQdpqqk6WJokeLvAs0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=W4dgAUrt; 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="W4dgAUrt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59D6F1F000E9; Tue, 25 Aug 2026 13:31:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787664710; bh=MZ84zKGddgDC3oE99M3PP0cGyoEbwYxgV9JyqAI0TZo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=W4dgAUrtsiHv/VnB9Y1Yvtrn/L/W21wbzBQygrihmqthCmWA0pvnfgXJEt9oscVqV ySyEFJ6ZDaq6OObLktnL8+BWY2LDBtjpH2dnJgCV7uv7/2N7Gedd4GadrWD/SKbHeC 50SqC5wuxNBQzjeMTBF7HrCbf/OyjEYhPLzaDu6g= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Federico Kirschbaum , Baul Lee , Jiri Kosina Subject: [PATCH 7.2 61/82] HID: pidff: fix OOB write when hid->inputs is empty Date: Tue, 25 Aug 2026 15:25:48 +0200 Message-ID: <20260825132543.915513037@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260825132541.560541185@linuxfoundation.org> References: <20260825132541.560541185@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 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Baul Lee commit 67bb1074e3d2d12fa059a9cc707e89398a4e4704 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/hid/usbhid/hid-pidff.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) --- a/drivers/hid/usbhid/hid-pidff.c +++ b/drivers/hid/usbhid/hid-pidff.c @@ -1539,13 +1539,20 @@ static int pidff_check_autocenter(struct 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)) {