From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C247E2F745C; Wed, 28 Jan 2026 15:48:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769615282; cv=none; b=lJuteUV/DbPemgvTRt+NitREGmPsi4nzMNEzjZVbs1QlcTtuMSkKtLMyuPK0khg1PQoGr27W2hfM2JgBVloVcn5Ty0hdACMpeCNNfvrHF9vLxA7E3zO4PVh5OsrSsrMcgSdXNea7qXKRXqbEy5d9RTZwmcVDZunVc79TEPgRkI8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769615282; c=relaxed/simple; bh=yw8yucNHTen4CrH6pE67F4qVZbVw4Y7kzYjusp2HCms=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BUp2sHhrL3r6qVvzajz1wwiVxVJtVrAJT3Vb7NwuQ0zszyemMCjcMHT/vXbDfD0nm+swrFxD+TrKxn/MLgX681hl/LEMk7N17lw6bzKeT/iRQ1Nsri2TdAdE069VZyBz+sZ1Xhpyf5QBwd90a9DTFs2f5QqfLfk0VHuZn5FE09o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=t31gqjN6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="t31gqjN6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF7C4C4CEF1; Wed, 28 Jan 2026 15:48:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769615282; bh=yw8yucNHTen4CrH6pE67F4qVZbVw4Y7kzYjusp2HCms=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t31gqjN6JwiFNeL9Vgg1bL38rg8smNumEV51tQibB3H1GNiKxJcAj7RgW8JupxXWH sNDz5u6NEh3rBxFEhIt9LGd2wiJ42OupcELnNEjVR2JwXxLImFdmjLZOtDgkjTRSzm kTOUH4wergQ77Md03Z9gRtFMBY3F7v2hr3n+1mrY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chenghai Huang , Yang Shen , Zhangfei Gao Subject: [PATCH 6.12 133/169] uacce: ensure safe queue release with state management Date: Wed, 28 Jan 2026 16:23:36 +0100 Message-ID: <20260128145338.793780110@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260128145334.006287341@linuxfoundation.org> References: <20260128145334.006287341@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org 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: Chenghai Huang commit 26c08dabe5475d99a13f353d8dd70e518de45663 upstream. Directly calling `put_queue` carries risks since it cannot guarantee that resources of `uacce_queue` have been fully released beforehand. So adding a `stop_queue` operation for the UACCE_CMD_PUT_Q command and leaving the `put_queue` operation to the final resource release ensures safety. Queue states are defined as follows: - UACCE_Q_ZOMBIE: Initial state - UACCE_Q_INIT: After opening `uacce` - UACCE_Q_STARTED: After `start` is issued via `ioctl` When executing `poweroff -f` in virt while accelerator are still working, `uacce_fops_release` and `uacce_remove` may execute concurrently. This can cause `uacce_put_queue` within `uacce_fops_release` to access a NULL `ops` pointer. Therefore, add state checks to prevent accessing freed pointers. Fixes: 015d239ac014 ("uacce: add uacce driver") Cc: stable@vger.kernel.org Signed-off-by: Chenghai Huang Signed-off-by: Yang Shen Acked-by: Zhangfei Gao Link: https://patch.msgid.link/20251202061256.4158641-5-huangchenghai2@huawei.com Signed-off-by: Greg Kroah-Hartman --- drivers/misc/uacce/uacce.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) --- a/drivers/misc/uacce/uacce.c +++ b/drivers/misc/uacce/uacce.c @@ -40,20 +40,34 @@ static int uacce_start_queue(struct uacc return 0; } -static int uacce_put_queue(struct uacce_queue *q) +static int uacce_stop_queue(struct uacce_queue *q) { struct uacce_device *uacce = q->uacce; - if ((q->state == UACCE_Q_STARTED) && uacce->ops->stop_queue) + if (q->state != UACCE_Q_STARTED) + return 0; + + if (uacce->ops->stop_queue) uacce->ops->stop_queue(q); - if ((q->state == UACCE_Q_INIT || q->state == UACCE_Q_STARTED) && - uacce->ops->put_queue) + q->state = UACCE_Q_INIT; + + return 0; +} + +static void uacce_put_queue(struct uacce_queue *q) +{ + struct uacce_device *uacce = q->uacce; + + uacce_stop_queue(q); + + if (q->state != UACCE_Q_INIT) + return; + + if (uacce->ops->put_queue) uacce->ops->put_queue(q); q->state = UACCE_Q_ZOMBIE; - - return 0; } static long uacce_fops_unl_ioctl(struct file *filep, @@ -80,7 +94,7 @@ static long uacce_fops_unl_ioctl(struct ret = uacce_start_queue(q); break; case UACCE_CMD_PUT_Q: - ret = uacce_put_queue(q); + ret = uacce_stop_queue(q); break; default: if (uacce->ops->ioctl)