From 0dc8fe5985e01f238e7dc64ff1733cc0291811e8 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Wed, 2 Oct 2013 11:23:37 +0200 Subject: [PATCH] drm: introduce drm_dev_free() to fix error paths The error paths in DRM bus drivers currently leak memory as they don't correctly revert drm_dev_alloc(). Introduce drm_dev_free() to free DRM devices which haven't been registered, yet. We must be careful not to introduce any side-effects with cleanups done in drm_dev_free(). drm_ht_remove(), drm_ctxbitmap_cleanup() and drm_gem_destroy() are all fine in that regard. Signed-off-by: David Herrmann Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_pci.c | 2 +- drivers/gpu/drm/drm_platform.c | 2 +- drivers/gpu/drm/drm_stub.c | 35 ++++++++++++++++++++++++---------- drivers/gpu/drm/drm_usb.c | 2 +- include/drm/drmP.h | 1 + 5 files changed, 29 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c index 743589dc47ce..cabe2bd702ae 100644 --- a/drivers/gpu/drm/drm_pci.c +++ b/drivers/gpu/drm/drm_pci.c @@ -354,7 +354,7 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent, err_pci: pci_disable_device(pdev); err_free: - kfree(dev); + drm_dev_free(dev); return ret; } EXPORT_SYMBOL(drm_get_pci_dev); diff --git a/drivers/gpu/drm/drm_platform.c b/drivers/gpu/drm/drm_platform.c index a0f91f85651f..fc24fee8ec83 100644 --- a/drivers/gpu/drm/drm_platform.c +++ b/drivers/gpu/drm/drm_platform.c @@ -64,7 +64,7 @@ static int drm_get_platform_dev(struct platform_device *platdev, return 0; err_free: - kfree(dev); + drm_dev_free(dev); return ret; } diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index 432994aafc3b..3b5b07482de8 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -363,7 +363,6 @@ static void drm_unplug_minor(struct drm_minor *minor) */ void drm_put_dev(struct drm_device *dev) { - struct drm_driver *driver; struct drm_map_list *r_list, *list_temp; DRM_DEBUG("\n"); @@ -372,7 +371,6 @@ void drm_put_dev(struct drm_device *dev) DRM_ERROR("cleanup called no dev\n"); return; } - driver = dev->driver; drm_lastclose(dev); @@ -386,9 +384,6 @@ void drm_put_dev(struct drm_device *dev) list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) drm_rmmap(dev, r_list->map); - drm_ht_remove(&dev->map_hash); - - drm_ctxbitmap_cleanup(dev); if (drm_core_check_feature(dev, DRIVER_MODESET)) drm_put_minor(&dev->control); @@ -396,14 +391,11 @@ void drm_put_dev(struct drm_device *dev) if (dev->render) drm_put_minor(&dev->render); - if (driver->driver_features & DRIVER_GEM) - drm_gem_destroy(dev); - drm_put_minor(&dev->primary); list_del(&dev->driver_item); - kfree(dev->devname); - kfree(dev); + + drm_dev_free(dev); } EXPORT_SYMBOL(drm_put_dev); @@ -501,6 +493,29 @@ struct drm_device *drm_dev_alloc(struct drm_driver *driver, } EXPORT_SYMBOL(drm_dev_alloc); +/** + * drm_dev_free - Free DRM device + * @dev: DRM device to free + * + * Free a DRM device that has previously been allocated via drm_dev_alloc(). + * You must not use kfree() instead or you will leak memory. + * + * This must not be called once the device got registered. Use drm_put_dev() + * instead, which then calls drm_dev_free(). + */ +void drm_dev_free(struct drm_device *dev) +{ + if (dev->driver->driver_features & DRIVER_GEM) + drm_gem_destroy(dev); + + drm_ctxbitmap_cleanup(dev); + drm_ht_remove(&dev->map_hash); + + kfree(dev->devname); + kfree(dev); +} +EXPORT_SYMBOL(drm_dev_free); + /** * drm_dev_register - Register DRM device * @dev: Device to register diff --git a/drivers/gpu/drm/drm_usb.c b/drivers/gpu/drm/drm_usb.c index 5ef353f77b5a..b179b70e7853 100644 --- a/drivers/gpu/drm/drm_usb.c +++ b/drivers/gpu/drm/drm_usb.c @@ -29,7 +29,7 @@ int drm_get_usb_dev(struct usb_interface *interface, return 0; err_free: - kfree(dev); + drm_dev_free(dev); return ret; } diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 1973f7966511..537833c9ab83 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1642,6 +1642,7 @@ static __inline__ void drm_core_dropmap(struct drm_local_map *map) struct drm_device *drm_dev_alloc(struct drm_driver *driver, struct device *parent); +void drm_dev_free(struct drm_device *dev); int drm_dev_register(struct drm_device *dev, unsigned long flags); int drm_get_minor(struct drm_device *dev, struct drm_minor **minor, int type); /*@}*/ -- GitLab