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 9D1423AFB19; Sat, 12 Sep 2026 18:36:53 +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=1789238216; cv=none; b=CWy3Zz9h79Cgb/mffWZZ2kwkU3K2IxxyiBBEcT/5HRYlv7zqJOxlN3xiOilaA8UV/6EZCXo/91Yt5fQqFjC/kOECUyA7HB6AAA8he5mVXsWju/v5Jz1U/7hzG25fESXXL/ZZyuichtRut/M4HF4G4330aFfhPToi4oVgJVxk6kk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789238216; c=relaxed/simple; bh=pFp4C6f4r1VzWDSt3Zu6HPxcxeFMqzLqVWud4pCByGU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uULe9kQHBLmC/LuSlf8m9hY9b+azSkiRku1m4VnNj3Z4Lo7pi7wQGw1RKA5c6OTkuNe4s2Gn3p6aHsU2ZfLcKHdXQaFsHohDay/KwRo9YonBC+/qq2V40cvXj3j7at0YWleBX8WHmV1BJJ/7qnaYJVIu743vXLvFt29IYzUM8Ew= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ATtxUpk3; 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="ATtxUpk3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C263A1F000FF; Sat, 12 Sep 2026 18:36:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789238213; bh=eegktZFIOHD97ANmVd9CsM0gDLTw6+hy78RXsj7Q83g=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ATtxUpk3B9Qv4+82d+cLo5qPo78juBlHQYcs0/0leYBhG3GxkUfavzVyX7IYXhWw9 vUhxS2MWI4gT4RIAoy46wKebhFMN1+WJ/Ke4U+XUQ+f/pbOsclNvViOUCa7bZCrmUg 5B736yEDtajebP1rKvEw4rI10CkiUn7q6W32UIjg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+9eebf5f6544c5e873858@syzkaller.appspotmail.com, Philipp Weber , Jiri Kosina , Sasha Levin Subject: [PATCH 5.15 399/935] HID: core: quiesce input in hid_hw_stop() to prevent use-after-free Date: Sat, 12 Sep 2026 08:57:09 +0200 Message-ID: <20260912065535.974542328@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065526.833703348@linuxfoundation.org> References: <20260912065526.833703348@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Philipp Weber [ Upstream commit a4bc41504690b7d7064931909874f5b98cd148b6 ] A driver's probe calls hid_device_io_start() to enable input delivery, then fails at a later initialization step and unwinds via hid_hw_stop(). The unwind frees struct hidraw via hidraw_disconnect() while in-flight HID reports may still be running on another CPU, dereferencing the freed object through hidraw_report_event(). syzbot reports the resulting use-after-free for the corsair-psu HID driver. Edward Adam Davis posted a per-driver fix for corsair-psu that adds an explicit hid_device_io_stop() before hid_hw_stop() in the probe error path ("hwmon: prevent packets from going to driver for probe", 2026-04-28). Auditing the tree shows 15 drivers call hid_device_io_start(); 7 also call hid_device_io_stop() and 8 do not: drivers calling hid_device_io_start() without a matching hid_device_io_stop() before hid_hw_stop(): drivers/hwmon/corsair-psu.c (fix posted by Edward) drivers/hwmon/corsair-cpro.c drivers/hwmon/nzxt-kraken3.c drivers/hwmon/nzxt-smart2.c drivers/hwmon/gigabyte_waterforce.c drivers/hid/hid-logitech-dj.c drivers/hid/hid-nintendo.c drivers/hid/hid-mcp2221.c Roughly half of all callers of the API are exposed. Centralize the quiesce in hid_hw_stop() so callers do not have to remember the matching stop: if a driver has left hdev->io_started true on entry, call hid_device_io_stop() before hid_disconnect(). For the 7 drivers that already call hid_device_io_stop() correctly, hdev->io_started is false on entry, the guard short-circuits, and behavior is unchanged. No Fixes: tag because the affected drivers gained their hid_device_io_start() calls independently over years; the bug is a class-wide API misuse rather than a regression from one commit. Reported-by: syzbot+9eebf5f6544c5e873858@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=9eebf5f6544c5e873858 Signed-off-by: Philipp Weber Signed-off-by: Jiri Kosina Signed-off-by: Sasha Levin --- drivers/hid/hid-core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 7144bd2c1153f..962c3ebc46bd6 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -2141,9 +2141,16 @@ EXPORT_SYMBOL_GPL(hid_hw_start); * * This is usually called from remove function or from probe when something * failed and hid_hw_start was called already. + * + * If the caller enabled HID input via hid_device_io_start() and is unwinding + * without an explicit hid_device_io_stop(), quiesce input first so that + * in-flight reports cannot reach handlers (e.g. hidraw_report_event) whose + * backing objects hid_disconnect() is about to free. */ void hid_hw_stop(struct hid_device *hdev) { + if (hdev->io_started) + hid_device_io_stop(hdev); hid_disconnect(hdev); hdev->ll_driver->stop(hdev); } -- 2.53.0