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 B72D025B0AA; Thu, 20 Aug 2026 15:25:13 +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=1787239514; cv=none; b=X+T/SUx9lMwk47xcSb98aPtTETrafjGJn8gE19GGTts2RpdcObdw3WFAMAvaJgWtwwqH8m8E4o5rQHjOgTmhSLQeQgHSYR0tcwsNuPv/Jl9CKrU+EwtdsbIsHawsWnnHZh4UeaHaYToOja2gCDU231jU320UsxZRXbpyQ4/1CEY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787239514; c=relaxed/simple; bh=b79CCpYfuPBnsXhq9G1x2ebcy/doBx2zWGm63b1uRVY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oUUlTXCYaekW7fox1cBQxaQbwaqi4pTiyI6S8m1uSe8P+NxUgoXhRP3NwO+YCAqIkYWIF2weCS9UUs7tQR6dRUZRXnhQwkAVdWaTLcJl4SICqF2XE7KiqFxRvrti+6LZLEPl9hCrwpK8YNt/eVV8m0bJ1C2ARx+/aJki/8N58qM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=PiB+DGkm; 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="PiB+DGkm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA5671F000E9; Thu, 20 Aug 2026 15:25:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787239513; bh=ErRcq/3zfoegkt0gN1scT2mWALQu4CyOCzCf/KXk624=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=PiB+DGkmOzmhqMjKFz8eQPl86GEslXVpQrY5LU1TQNMTkVU2X7bTsBfaPattCqNd4 OE6eEUJ2ysS5nizUfsdLiBsL9d54EAtg6thyUrD7gOsqJebgl8vXl6n7dcDvLhU44D R5t8As1H6Mk7cHirfLHKJsc0/KR9enFa8/SPEdLs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, sashiko-bot@kernel.org, Dmitry Torokhov Subject: [PATCH 6.12 058/220] Input: sur40 - fix input device registration ordering Date: Thu, 20 Aug 2026 16:54:08 +0200 Message-ID: <20260820145225.237694756@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145223.480031205@linuxfoundation.org> References: <20260820145223.480031205@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Torokhov commit 9da976eb649c9e2f588a4499410e4d8af687925f upstream. In sur40_probe(), input_register_device() was previously called early before the V4L2 video device and vb2_queue components were fully initialized. If userspace opened the input device immediately upon registration, sur40_open() would trigger and start the sur40_poll() worker thread. This worker thread invokes sur40_process_video() and accesses the uninitialized vb2_queue structure, leading to a data race and potential system crash. Furthermore, if V4L2 or video registration failed after input_register_device() succeeded, the error path fell through to calling input_free_device() on a successfully registered device instead of input_unregister_device(), corrupting input core state. Move input_register_device() to the very end of sur40_probe(). This ensures the V4L2 and video queue structures are fully initialized before polling can start, and naturally resolves the error path bug since input_free_device() is now only called when input registration has not yet occurred. To maintain strict LIFO (Last-In, First-Out) teardown ordering, also move input_unregister_device() to the very beginning of sur40_disconnect(). This guarantees that the input polling worker thread is stopped before V4L2 video components or control handlers are unregistered. Reported-by: sashiko-bot@kernel.org Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Link: https://patch.msgid.link/20260616051235.1549517-1-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman --- drivers/input/touchscreen/sur40.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) --- a/drivers/input/touchscreen/sur40.c +++ b/drivers/input/touchscreen/sur40.c @@ -725,21 +725,13 @@ static int sur40_probe(struct usb_interf goto err_free_input; } - /* register the polled input device */ - error = input_register_device(input); - if (error) { - dev_err(&interface->dev, - "Unable to register polled input device."); - goto err_free_buffer; - } - /* register the video master device */ snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG); error = v4l2_device_register(sur40->dev, &sur40->v4l2); if (error) { dev_err(&interface->dev, "Unable to register video master device."); - goto err_unreg_v4l2; + goto err_free_buffer; } /* initialize the lock and subdevice */ @@ -798,6 +790,14 @@ static int sur40_probe(struct usb_interf goto err_unreg_video; } + /* register the polled input device */ + error = input_register_device(input); + if (error) { + dev_err(&interface->dev, + "Unable to register polled input device."); + goto err_unreg_video; + } + /* we can register the device now, as it is ready */ usb_set_intfdata(interface, sur40); dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC); @@ -823,11 +823,12 @@ static void sur40_disconnect(struct usb_ { struct sur40_state *sur40 = usb_get_intfdata(interface); + input_unregister_device(sur40->input); + v4l2_ctrl_handler_free(&sur40->hdl); video_unregister_device(&sur40->vdev); v4l2_device_unregister(&sur40->v4l2); - input_unregister_device(sur40->input); kfree(sur40->bulk_in_buffer); kfree(sur40);