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 8737D246333; Tue, 26 Aug 2025 13:05:25 +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=1756213525; cv=none; b=TCiQbOCheEtY7yXw/HzK0u60d2JxXVEHivqhP0+v/VKpengowf/PrjuuTOSCPU2CRSXhqUpCiG2c4Akipp1mrsmdCd0kcjqO4+dcXaQv524QCNRnX5n+iTN+bmecXZqjaEf6lahh8T5RxO5szVjXOYPSMKR27t94663eh8NPEwg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756213525; c=relaxed/simple; bh=IIYbwUyRrluSIsDnICo2Up4wF7Pgl3US9sOQZajsTHY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JV0p8nDVeIBhY+kECGgGuhoOBAjEXsckqLhujg/8PjfuPXqpnoab05c5nCoKrrAjn5pwt24lluP33VFhuJEvlYgtNarxfJThQetrG2RLU6r1bltFHDcgEJJD+x4PmR20Ya8wt4QeqJekkC6U1a+6G6ljAJbJLqkchthtQdyeDuU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=X6yO2YVB; 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="X6yO2YVB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 09E69C4CEF1; Tue, 26 Aug 2025 13:05:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756213525; bh=IIYbwUyRrluSIsDnICo2Up4wF7Pgl3US9sOQZajsTHY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=X6yO2YVB1XRggT1nSMk8XXTlop76JlqDtproZ/Kh5IDvdo8bB98CWud3YGi5iDQ1P cKgAfZbSgioYp0avk1/ppl6FJq0XnRKDO39li9UpC+8Zw+z0+XI1s4ZNR+x8Ni+0Xy eq9YRfrFvBQLCLrOLQB8tiEXMk7E8pQM71KyQ4Fc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Giovanni Cabiddu , Ahsan Atta , Herbert Xu Subject: [PATCH 6.6 343/587] crypto: qat - flush misc workqueue during device shutdown Date: Tue, 26 Aug 2025 13:08:12 +0200 Message-ID: <20250826111001.640801116@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110952.942403671@linuxfoundation.org> References: <20250826110952.942403671@linuxfoundation.org> User-Agent: quilt/0.68 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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Giovanni Cabiddu commit 3d4df408ba9bad2b205c7fb8afc1836a6a4ca88a upstream. Repeated loading and unloading of a device specific QAT driver, for example qat_4xxx, in a tight loop can lead to a crash due to a use-after-free scenario. This occurs when a power management (PM) interrupt triggers just before the device-specific driver (e.g., qat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains loaded. Since the driver uses a shared workqueue (`qat_misc_wq`) across all devices and owned by intel_qat.ko, a deferred routine from the device-specific driver may still be pending in the queue. If this routine executes after the driver is unloaded, it can dereference freed memory, resulting in a page fault and kernel crash like the following: BUG: unable to handle page fault for address: ffa000002e50a01c #PF: supervisor read access in kernel mode RIP: 0010:pm_bh_handler+0x1d2/0x250 [intel_qat] Call Trace: pm_bh_handler+0x1d2/0x250 [intel_qat] process_one_work+0x171/0x340 worker_thread+0x277/0x3a0 kthread+0xf0/0x120 ret_from_fork+0x2d/0x50 To prevent this, flush the misc workqueue during device shutdown to ensure that all pending work items are completed before the driver is unloaded. Note: This approach may slightly increase shutdown latency if the workqueue contains jobs from other devices, but it ensures correctness and stability. Fixes: e5745f34113b ("crypto: qat - enable power management for QAT GEN4") Signed-off-by: Giovanni Cabiddu Cc: stable@vger.kernel.org Reviewed-by: Ahsan Atta Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- drivers/crypto/intel/qat/qat_common/adf_common_drv.h | 1 + drivers/crypto/intel/qat/qat_common/adf_init.c | 1 + drivers/crypto/intel/qat/qat_common/adf_isr.c | 5 +++++ 3 files changed, 7 insertions(+) --- a/drivers/crypto/intel/qat/qat_common/adf_common_drv.h +++ b/drivers/crypto/intel/qat/qat_common/adf_common_drv.h @@ -193,6 +193,7 @@ void adf_exit_misc_wq(void); bool adf_misc_wq_queue_work(struct work_struct *work); bool adf_misc_wq_queue_delayed_work(struct delayed_work *work, unsigned long delay); +void adf_misc_wq_flush(void); #if defined(CONFIG_PCI_IOV) int adf_sriov_configure(struct pci_dev *pdev, int numvfs); void adf_disable_sriov(struct adf_accel_dev *accel_dev); --- a/drivers/crypto/intel/qat/qat_common/adf_init.c +++ b/drivers/crypto/intel/qat/qat_common/adf_init.c @@ -381,6 +381,7 @@ static void adf_dev_shutdown(struct adf_ hw_data->exit_admin_comms(accel_dev); adf_cleanup_etr_data(accel_dev); + adf_misc_wq_flush(); adf_dev_restore(accel_dev); } --- a/drivers/crypto/intel/qat/qat_common/adf_isr.c +++ b/drivers/crypto/intel/qat/qat_common/adf_isr.c @@ -386,3 +386,8 @@ bool adf_misc_wq_queue_delayed_work(stru { return queue_delayed_work(adf_misc_wq, work, delay); } + +void adf_misc_wq_flush(void) +{ + flush_workqueue(adf_misc_wq); +}