From nobody Sun Feb 8 12:58:16 2026 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1C57030F813; Fri, 14 Nov 2025 10:14:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.81 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763115281; cv=none; b=U4v8zk1SqdB85E36sMmnpUPFLo/P+k89NxLG6LIcrGwGJmVnf0RtbGUgd+33X/ANu8YrL/Gm4Xln5B10aHM1ylxHfVSv7SUxwjR9kTb+6cgMq2PWsrsql4Lgbzt4P3JQhusQ+JBpyBt6zppG+ACsfJIE83NWGL73vzmbTDzCVHs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763115281; c=relaxed/simple; bh=hQAm2cynmBS+7YWEysl94cgkydRizBZ4fkJ+yymE+cM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=mGLHwm90gHd6grDMh6mi4LWBtKFTPbFYSDYQTg/OihGDbuoae3HVOYTgjzlHv10JEYAsGoB4RwVX2HCagK0boFuQyjXF5NaVk4NxdrrFNFmYylaadxnVLc029donqRtvXJq4QM2fQaV4g+r8iNXMY+2TWJDcic3aMLZq5Ia1RXU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from DESKTOP-L0HPE2S (unknown [124.16.141.245]) by APP-03 (Coremail) with SMTP id rQCowABn99kIARdpN5e5AA--.34984S2; Fri, 14 Nov 2025 18:14:33 +0800 (CST) From: Haotian Zhang To: sean@mess.org, mchehab@kernel.org Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Haotian Zhang Subject: [PATCH] media: mceusb: fix race between device disconnection and urb callback Date: Fri, 14 Nov 2025 18:14:31 +0800 Message-ID: <20251114101432.2566-1-vulab@iscas.ac.cn> X-Mailer: git-send-email 2.50.1.windows.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: rQCowABn99kIARdpN5e5AA--.34984S2 X-Coremail-Antispam: 1UD129KBjvJXoW7ury5Jw1xCFW3uFyxtr1UKFg_yoW8GF4UpF W0gryFyFy8GF4UZw4DJa1kXayYqws5Gay2kFyru34Y9ws5Aa47ta4kGa45A3ykAFWUAFWq yw13J3yxuFZ8CaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvv14x267AKxVWUJVW8JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUXVWUAwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY1x0262kKe7AKxVWU AVWUtwCY02Avz4vE14v_Gw1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr 1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE 14v26r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7 IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E 87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73Uj IFyTuYvjfU0c_TUUUUU X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiBwkGA2kW984gTgAAsj Content-Type: text/plain; charset="utf-8" The mceusb_disconnect() function calls rc_unregister_device() before usb_kill_urb(), creating a race condition similar to the one fixed in commit 'f656cfbc7a29'. If rc_unregister_device() executes while the URB callback mceusb_dev_recv() is still running, mceusb_process_ir_data() may call ir_raw_event_store_with_filter() or ir_raw_event_handle() with a freed ir->rc->raw pointer, leading to a NULL pointer dereference. Call usb_kill_urb() before rc_unregister_device() to ensure all URB callbacks complete before freeing device resources. Fixes: d8b4b5822f51 ("[media] ir-core: make struct rc_dev the primary inter= face") Signed-off-by: Haotian Zhang --- drivers/media/rc/mceusb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/rc/mceusb.c b/drivers/media/rc/mceusb.c index 044767eb3a38..fb5c393dcb94 100644 --- a/drivers/media/rc/mceusb.c +++ b/drivers/media/rc/mceusb.c @@ -1845,8 +1845,8 @@ static void mceusb_dev_disconnect(struct usb_interfac= e *intf) =20 ir->usbdev =3D NULL; cancel_work_sync(&ir->kevent); - rc_unregister_device(ir->rc); usb_kill_urb(ir->urb_in); + rc_unregister_device(ir->rc); usb_free_urb(ir->urb_in); usb_free_coherent(dev, ir->len_in, ir->buf_in, ir->dma_in); usb_put_dev(dev); --=20 2.50.1.windows.1