From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Balakrishna Godavarthi , Marcel Holtmann , Sasha Levin Subject: [PATCH 4.19 092/361] Bluetooth: hci_qca: Remove hdev dereference in qca_close(). Date: Sun, 11 Nov 2018 14:17:19 -0800 Message-Id: <20181111221632.633226379@linuxfoundation.org> In-Reply-To: <20181111221619.915519183@linuxfoundation.org> References: <20181111221619.915519183@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Balakrishna Godavarthi [ Upstream commit c2d7827338618a9e73a3f892ca63d9082bb7a94d ] When flag KASAN is set, we are seeing an following crash while removing hci_uart module. [ 50.589909] Unable to handle kernel paging request at virtual address 6b6b6b6b6b6b73 [ 50.597902] Mem abort info: [ 50.600846] Exception class = DABT (current EL), IL = 32 bits [ 50.606959] SET = 0, FnV = 0 [ 50.610142] EA = 0, S1PTW = 0 [ 50.613396] Data abort info: [ 50.616401] ISV = 0, ISS = 0x00000004 [ 50.620373] CM = 0, WnR = 0 [ 50.623466] [006b6b6b6b6b6b73] address between user and kernel address ranges [ 50.630818] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 50.671670] PC is at qca_power_shutdown+0x28/0x100 [hci_uart] [ 50.677593] LR is at qca_close+0x74/0xb0 [hci_uart] [ 50.775689] Process rmmod (pid: 2144, stack limit = 0xffffff801ba90000) [ 50.782493] Call trace: [ 50.872150] [] qca_power_shutdown+0x28/0x100 [hci_uart] [ 50.879138] [] qca_close+0x74/0xb0 [hci_uart] [ 50.885238] [] hci_uart_unregister_device+0x44/0x50 [hci_uart] [ 50.892846] [] qca_serdev_remove+0x50/0x5c [hci_uart] [ 50.899654] [] serdev_drv_remove+0x28/0x38 [ 50.905489] [] device_release_driver_internal+0x140/0x1e4 [ 50.912653] [] driver_detach+0x78/0x84 [ 50.918121] [] bus_remove_driver+0x80/0xa8 [ 50.923942] [] driver_unregister+0x4c/0x58 [ 50.929768] [] qca_deinit+0x24/0x598 [hci_uart] [ 50.936045] [] hci_uart_exit+0x10/0x48 [hci_uart] [ 50.942495] [] SyS_delete_module+0x17c/0x224 This crash is due to dereference of hdev, after freeing it. Signed-off-by: Balakrishna Godavarthi Signed-off-by: Marcel Holtmann Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/bluetooth/hci_qca.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -167,7 +167,7 @@ struct qca_serdev { }; static int qca_power_setup(struct hci_uart *hu, bool on); -static void qca_power_shutdown(struct hci_dev *hdev); +static void qca_power_shutdown(struct hci_uart *hu); static void __serial_clock_on(struct tty_struct *tty) { @@ -609,7 +609,7 @@ static int qca_close(struct hci_uart *hu if (hu->serdev) { qcadev = serdev_device_get_drvdata(hu->serdev); if (qcadev->btsoc_type == QCA_WCN3990) - qca_power_shutdown(hu->hdev); + qca_power_shutdown(hu); else gpiod_set_value_cansleep(qcadev->bt_en, 0); @@ -1232,12 +1232,15 @@ static const struct qca_vreg_data qca_so .num_vregs = 4, }; -static void qca_power_shutdown(struct hci_dev *hdev) +static void qca_power_shutdown(struct hci_uart *hu) { - struct hci_uart *hu = hci_get_drvdata(hdev); + struct serdev_device *serdev = hu->serdev; + unsigned char cmd = QCA_WCN3990_POWEROFF_PULSE; host_set_baudrate(hu, 2400); - qca_send_power_pulse(hdev, QCA_WCN3990_POWEROFF_PULSE); + hci_uart_set_flow_control(hu, true); + serdev_device_write_buf(serdev, &cmd, sizeof(cmd)); + hci_uart_set_flow_control(hu, false); qca_power_setup(hu, false); } @@ -1413,7 +1416,7 @@ static void qca_serdev_remove(struct ser struct qca_serdev *qcadev = serdev_device_get_drvdata(serdev); if (qcadev->btsoc_type == QCA_WCN3990) - qca_power_shutdown(qcadev->serdev_hu.hdev); + qca_power_shutdown(&qcadev->serdev_hu); else clk_disable_unprepare(qcadev->susclk);