From: Hans de Goede Date: Tue, 14 Jun 2016 20:13:05 +0000 (-0500) Subject: usb: musb: sunxi: Fix NULL ptr deref when gadget is registered before musb X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=969a132723434f3723cc0606373785d19c1d2f05;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git usb: musb: sunxi: Fix NULL ptr deref when gadget is registered before musb Stop using the return value of platform_device_register_full() to get to the struct musb in sunxi_musb_work(). If a gadget has been registered (insmod-ed) before the musb driver, then musb_start will get called from the musb_core probe function and sunxi_musb_work() may run before platform_device_register_full() has returned. Instead store a pointer to struct musb in struct sunxi_glue when sunxi_musb_enable gets called. Note that sunxi_musb_enable always gets called before sunxi_musb_work() can run. Signed-off-by: Hans de Goede [b-liu@ti.com: revise subject prefix] Signed-off-by: Bin Liu Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/musb/sunxi.c b/drivers/usb/musb/sunxi.c index e7d46179b485..dc49041498a3 100644 --- a/drivers/usb/musb/sunxi.c +++ b/drivers/usb/musb/sunxi.c @@ -80,7 +80,8 @@ static struct musb *sunxi_musb; struct sunxi_glue { struct device *dev; - struct platform_device *musb; + struct musb *musb; + struct platform_device *musb_pdev; struct clk *clk; struct reset_control *rst; struct phy *phy; @@ -102,7 +103,7 @@ static void sunxi_musb_work(struct work_struct *work) return; if (test_and_clear_bit(SUNXI_MUSB_FL_HOSTMODE_PEND, &glue->flags)) { - struct musb *musb = platform_get_drvdata(glue->musb); + struct musb *musb = glue->musb; unsigned long flags; u8 devctl; @@ -337,6 +338,8 @@ static void sunxi_musb_enable(struct musb *musb) { struct sunxi_glue *glue = dev_get_drvdata(musb->controller->parent); + glue->musb = musb; + /* musb_core does not call us in a balanced manner */ if (test_and_set_bit(SUNXI_MUSB_FL_ENABLED, &glue->flags)) return; @@ -732,9 +735,9 @@ static int sunxi_musb_probe(struct platform_device *pdev) pinfo.data = &pdata; pinfo.size_data = sizeof(pdata); - glue->musb = platform_device_register_full(&pinfo); - if (IS_ERR(glue->musb)) { - ret = PTR_ERR(glue->musb); + glue->musb_pdev = platform_device_register_full(&pinfo); + if (IS_ERR(glue->musb_pdev)) { + ret = PTR_ERR(glue->musb_pdev); dev_err(&pdev->dev, "Error registering musb dev: %d\n", ret); goto err_unregister_usb_phy; } @@ -751,7 +754,7 @@ static int sunxi_musb_remove(struct platform_device *pdev) struct sunxi_glue *glue = platform_get_drvdata(pdev); struct platform_device *usb_phy = glue->usb_phy; - platform_device_unregister(glue->musb); /* Frees glue ! */ + platform_device_unregister(glue->musb_pdev); /* Frees glue ! */ usb_phy_generic_unregister(usb_phy); return 0;