fsl_usb2_udc: Fix oops on probe failure.

In some circumstances when fsl_udc_probe fails udc_controller is freed but
the pointer remains non-NULL. fsl_udc_remove will then try and teardown
the partly initialized and freed controller structure resulting in an oops.
This patch ensures udc_controller is either NULL or fully initialized after
fsl_udc_probe.

Signed-off-by: Will Newton <will.newton@gmail.com>
Acked-by: Li Yang <leoli@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 17 insertions, 15 deletions

diff --git a/drivers/usb/gadget/fsl_usb2_udc.c b/drivers/usb/gadget/fsl_usb2_udc.c
index 0492441bc0ba..091bb55c9aa7 100644
--- a/drivers/usb/gadget/fsl_usb2_udc.c
+++ b/drivers/usb/gadget/fsl_usb2_udc.c
@@ -2244,21 +2244,21 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!res) {
-                kfree(udc_controller);
-                return -ENXIO;
+                ret = -ENXIO;
+                goto err_kfree;
         }
 
         if (!request_mem_region(res->start, res->end - res->start + 1,
                                 driver_name)) {
                 ERR("request mem region for %s failed\n", pdev->name);
-                kfree(udc_controller);
-                return -EBUSY;
+                ret = -EBUSY;
+                goto err_kfree;
         }
 
         dr_regs = ioremap(res->start, res->end - res->start + 1);
         if (!dr_regs) {
                 ret = -ENOMEM;
-                goto err1;
+                goto err_release_mem_region;
         }
 
         usb_sys_regs = (struct usb_sys_interface *)
@@ -2269,7 +2269,7 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
         if (!(dccparams & DCCPARAMS_DC)) {
                 ERR("This SOC doesn't support device role\n");
                 ret = -ENODEV;
-                goto err2;
+                goto err_iounmap;
         }
         /* Get max device endpoints */
         /* DEN is bidirectional ep number, max_ep doubles the number */
@@ -2278,7 +2278,7 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
         udc_controller->irq = platform_get_irq(pdev, 0);
         if (!udc_controller->irq) {
                 ret = -ENODEV;
-                goto err2;
+                goto err_iounmap;
         }
 
         ret = request_irq(udc_controller->irq, fsl_udc_irq, IRQF_SHARED,
@@ -2286,14 +2286,14 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
         if (ret != 0) {
                 ERR("cannot request irq %d err %d\n",
                                 udc_controller->irq, ret);
-                goto err2;
+                goto err_iounmap;
         }
 
         /* Initialize the udc structure including QH member and other member */
         if (struct_udc_setup(udc_controller, pdev)) {
                 ERR("Can't initialize udc data structure\n");
                 ret = -ENOMEM;
-                goto err3;
+                goto err_free_irq;
         }
 
         /* initialize usb hw reg except for regs for EP,
@@ -2314,7 +2314,7 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
         udc_controller->gadget.dev.parent = &pdev->dev;
         ret = device_register(&udc_controller->gadget.dev);
         if (ret < 0)
-                goto err3;
+                goto err_free_irq;
 
         /* setup QH and epctrl for ep0 */
         ep0_setup(udc_controller);
@@ -2344,20 +2344,22 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
                         DTD_ALIGNMENT, UDC_DMA_BOUNDARY);
         if (udc_controller->td_pool == NULL) {
                 ret = -ENOMEM;
-                goto err4;
+                goto err_unregister;
         }
         create_proc_file();
         return 0;
 
-err4:
+err_unregister:
         device_unregister(&udc_controller->gadget.dev);
-err3:
+err_free_irq:
         free_irq(udc_controller->irq, udc_controller);
-err2:
+err_iounmap:
         iounmap(dr_regs);
-err1:
+err_release_mem_region:
         release_mem_region(res->start, res->end - res->start + 1);
+err_kfree:
         kfree(udc_controller);
+        udc_controller = NULL;
         return ret;
 }