| From 23f6626bb4c53ab68f3302fa93ca3d9ce8d4350b Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 16 Jul 2020 14:09:48 +0200 |
| Subject: usb: dwc2: Fix error path in gadget registration |
| |
| From: Marek Szyprowski <m.szyprowski@samsung.com> |
| |
| [ Upstream commit 33a06f1300a79cfd461cea0268f05e969d4f34ec ] |
| |
| When gadget registration fails, one should not call usb_del_gadget_udc(). |
| Ensure this by setting gadget->udc to NULL. Also in case of a failure |
| there is no need to disable low-level hardware, so return immiedetly |
| instead of jumping to error_init label. |
| |
| This fixes the following kernel NULL ptr dereference on gadget failure |
| (can be easily triggered with g_mass_storage without any module |
| parameters): |
| |
| dwc2 12480000.hsotg: dwc2_check_params: Invalid parameter besl=1 |
| dwc2 12480000.hsotg: dwc2_check_params: Invalid parameter g_np_tx_fifo_size=1024 |
| dwc2 12480000.hsotg: EPs: 16, dedicated fifos, 7808 entries in SPRAM |
| Mass Storage Function, version: 2009/09/11 |
| LUN: removable file: (no medium) |
| no file given for LUN0 |
| g_mass_storage 12480000.hsotg: failed to start g_mass_storage: -22 |
| 8<--- cut here --- |
| Unable to handle kernel NULL pointer dereference at virtual address 00000104 |
| pgd = (ptrval) |
| [00000104] *pgd=00000000 |
| Internal error: Oops: 805 [#1] PREEMPT SMP ARM |
| Modules linked in: |
| CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.8.0-rc5 #3133 |
| Hardware name: Samsung Exynos (Flattened Device Tree) |
| Workqueue: events deferred_probe_work_func |
| PC is at usb_del_gadget_udc+0x38/0xc4 |
| LR is at __mutex_lock+0x31c/0xb18 |
| ... |
| Process kworker/0:1 (pid: 12, stack limit = 0x(ptrval)) |
| Stack: (0xef121db0 to 0xef122000) |
| ... |
| [<c076bf3c>] (usb_del_gadget_udc) from [<c0726bec>] (dwc2_hsotg_remove+0x10/0x20) |
| [<c0726bec>] (dwc2_hsotg_remove) from [<c0711208>] (dwc2_driver_probe+0x57c/0x69c) |
| [<c0711208>] (dwc2_driver_probe) from [<c06247c0>] (platform_drv_probe+0x6c/0xa4) |
| [<c06247c0>] (platform_drv_probe) from [<c0621df4>] (really_probe+0x200/0x48c) |
| [<c0621df4>] (really_probe) from [<c06221e8>] (driver_probe_device+0x78/0x1fc) |
| [<c06221e8>] (driver_probe_device) from [<c061fcd4>] (bus_for_each_drv+0x74/0xb8) |
| [<c061fcd4>] (bus_for_each_drv) from [<c0621b54>] (__device_attach+0xd4/0x16c) |
| [<c0621b54>] (__device_attach) from [<c0620c98>] (bus_probe_device+0x88/0x90) |
| [<c0620c98>] (bus_probe_device) from [<c06211b0>] (deferred_probe_work_func+0x3c/0xd0) |
| [<c06211b0>] (deferred_probe_work_func) from [<c0149280>] (process_one_work+0x234/0x7dc) |
| [<c0149280>] (process_one_work) from [<c014986c>] (worker_thread+0x44/0x51c) |
| [<c014986c>] (worker_thread) from [<c0150b1c>] (kthread+0x158/0x1a0) |
| [<c0150b1c>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20) |
| Exception stack(0xef121fb0 to 0xef121ff8) |
| ... |
| ---[ end trace 9724c2fc7cc9c982 ]--- |
| |
| While fixing this also fix the double call to dwc2_lowlevel_hw_disable() |
| if dr_mode is set to USB_DR_MODE_PERIPHERAL. In such case low-level |
| hardware is already disabled before calling usb_add_gadget_udc(). That |
| function correctly preserves low-level hardware state, there is no need |
| for the second unconditional dwc2_lowlevel_hw_disable() call. |
| |
| Fixes: 207324a321a8 ("usb: dwc2: Postponed gadget registration to the udc class driver") |
| Acked-by: Minas Harutyunyan <hminas@synopsys.com> |
| Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> |
| Signed-off-by: Felipe Balbi <balbi@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/usb/dwc2/platform.c | 4 +++- |
| 1 file changed, 3 insertions(+), 1 deletion(-) |
| |
| diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c |
| index 797afa99ef3b4..4ad85fa2c9328 100644 |
| --- a/drivers/usb/dwc2/platform.c |
| +++ b/drivers/usb/dwc2/platform.c |
| @@ -543,6 +543,7 @@ static int dwc2_driver_probe(struct platform_device *dev) |
| if (hsotg->gadget_enabled) { |
| retval = usb_add_gadget_udc(hsotg->dev, &hsotg->gadget); |
| if (retval) { |
| + hsotg->gadget.udc = NULL; |
| dwc2_hsotg_remove(hsotg); |
| goto error_init; |
| } |
| @@ -554,7 +555,8 @@ static int dwc2_driver_probe(struct platform_device *dev) |
| if (hsotg->params.activate_stm_id_vb_detection) |
| regulator_disable(hsotg->usb33d); |
| error: |
| - dwc2_lowlevel_hw_disable(hsotg); |
| + if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) |
| + dwc2_lowlevel_hw_disable(hsotg); |
| return retval; |
| } |
| |
| -- |
| 2.25.1 |
| |
