/* * drivers/usb/core/file.c * * (C) Copyright Linus Torvalds 1999 * (C) Copyright Johannes Erdfelt 1999-2001 * (C) Copyright Andreas Gal 1999 * (C) Copyright Gregory P. Smith 1999 * (C) Copyright Deti Fliegl 1999 (new USB architecture) * (C) Copyright Randy Dunlap 2000 * (C) Copyright David Brownell 2000-2001 (kernel hotplug, usb_device_id, * more docs, etc) * (C) Copyright Yggdrasil Computing, Inc. 2000 * (usb_device_id matching changes by Adam J. Richter) * (C) Copyright Greg Kroah-Hartman 2002-2003 * * Released under the GPLv2 only. * SPDX-License-Identifier: GPL-2.0 */ #include #include #include #include #include #include #include "usb.h" #define MAX_USB_MINORS 256 static const struct file_operations *usb_minors[MAX_USB_MINORS]; static DECLARE_RWSEM(minor_rwsem); static int usb_open(struct inode *inode, struct file *file) { int err = -ENODEV; const struct file_operations *new_fops; down_read(&minor_rwsem); new_fops = fops_get(usb_minors[iminor(inode)]); if (!new_fops) goto done; replace_fops(file, new_fops); /* Curiouser and curiouser... NULL ->open() as "no device" ? */ if (file->f_op->open) err = file->f_op->open(inode, file); done: up_read(&minor_rwsem); return err; } static const struct file_operations usb_fops = { .owner = THIS_MODULE, .open = usb_open, .llseek = noop_llseek, }; static struct usb_class { struct kref kref; struct class *class; } *usb_class; static char *usb_devnode(struct device *dev, umode_t *mode) { struct usb_class_driver *drv; drv = dev_get_drvdata(dev); if (!drv || !drv->devnode) return NULL; return drv->devnode(dev, mode); } static int init_usb_class(void) { int result = 0; if (usb_class != NULL) { kref_get(&usb_class->kref); goto exit; } usb_class = kmalloc(sizeof(*usb_class), GFP_KERNEL); if (!usb_class) { result = -ENOMEM; goto exit; } kref_init(&usb_class->kref); usb_class->class = class_create(THIS_MODULE, "usbmisc"); if (IS_ERR(usb_class->class)) { result = PTR_ERR(usb_class->class); printk(KERN_ERR "class_create failed for usb devices\n"); kfree(usb_class); usb_class = NULL; goto exit; } usb_class->class->devnode = usb_devnode; exit: return result; } static void release_usb_class(struct kref *kref) { /* Ok, we cheat as we know we only have one usb_class */ class_destroy(usb_class->class); kfree(usb_class); usb_class = NULL; } static void destroy_usb_class(void) { if (usb_class) kref_put(&usb_class->kref, release_usb_class); } int usb_major_init(void) { int error; error = register_chrdev(USB_MAJOR, "usb", &usb_fops); if (error) printk(KERN_ERR "Unable to get major %d for usb devices\n", USB_MAJOR); return error; } void usb_major_cleanup(void) { unregister_chrdev(USB_MAJOR, "usb"); } /** * usb_register_dev - register a USB device, and ask for a minor number * @intf: pointer to the usb_interface that is being registered * @class_driver: pointer to the usb_class_driver for this device * * This should be called by all USB drivers that use the USB major number. * If CONFIG_USB_DYNAMIC_MINORS is enabled, the minor number will be * dynamically allocated out of the list of available ones. If it is not * enabled, the minor number will be based on the next available free minor, * starting at the class_driver->minor_base. * * This function also creates a usb class device in the sysfs tree. * * usb_deregister_dev() must be called when the driver is done with * the minor numbers given out by this function. * * Return: -EINVAL if something bad happens with trying to register a * device, and 0 on success. */ int usb_register_dev(struct usb_interface *intf, struct usb_class_driver *class_driver) { int retval; int minor_base = class_driver->minor_base; int minor; char name[20]; #ifdef CONFIG_USB_DYNAMIC_MINORS /* * We don't care what the device tries to start at, we want to start * at zero to pack the devices into the smallest available space with * no holes in the minor range. */ minor_base = 0; #endif if (class_driver->fops == NULL) return -EINVAL; if (intf->minor >= 0) return -EADDRINUSE; retval = init_usb_class(); if (retval) return retval; dev_dbg(&intf->dev, "looking for a minor, starting at %d\n", minor_base); down_write(&minor_rwsem); for (minor = minor_base; minor < MAX_USB_MINORS; ++minor) { if (usb_minors[minor]) continue; usb_minors[minor] = class_driver->fops; intf->minor = minor; break; } up_write(&minor_rwsem); if (intf->minor < 0) return -EXFULL; /* create a usb class device for this usb interface */ snprintf(name, sizeof(name), class_driver->name, minor - minor_base); intf->usb_dev = device_create(usb_class->class, &intf->dev, MKDEV(USB_MAJOR, minor), class_driver, "%s", kbasename(name)); if (IS_ERR(intf->usb_dev)) { down_write(&minor_rwsem); usb_minors[minor] = NULL; intf->minor = -1; up_write(&minor_rwsem); retval = PTR_ERR(intf->usb_dev); } return retval; } EXPORT_SYMBOL_GPL(usb_register_dev); /** * usb_deregister_dev - deregister a USB device's dynamic minor. * @intf: pointer to the usb_interface that is being deregistered * @class_driver: pointer to the usb_class_driver for this device * * Used in conjunction with usb_register_dev(). This function is called * when the USB driver is finished with the minor numbers gotten from a * call to usb_register_dev() (usually when the device is disconnected * from the system.) * * This function also removes the usb class device from the sysfs tree. * * This should be called by all drivers that use the USB major number. */ void usb_deregister_dev(struct usb_interface *intf, struct usb_class_driver *class_driver) { if (intf->minor == -1) return; dev_dbg(&intf->dev, "removing %d minor\n", intf->minor); down_write(&minor_rwsem); usb_minors[intf->minor] = NULL; up_write(&minor_rwsem); device_destroy(usb_class->class, MKDEV(USB_MAJOR, intf->minor)); intf->usb_dev = NULL; intf->minor = -1; destroy_usb_class(); } EXPORT_SYMBOL_GPL(usb_deregister_dev); div class='commit-subject'>drm/atomic: Fix double free in drm_atomic_state_default_clear
drm_atomic_helper_page_flip and drm_atomic_ioctl set their own events in crtc_state->event. But when it's set the event is freed in 2 places. Solve this by only freeing the event in the atomic ioctl when it allocated its own event. This has been broken twice. The first time when the code was introduced, but only in the corner case when an event is allocated, but more crtc's were included by atomic check and then failing. This can mostly happen when you do an atomic modeset in i915 and the display clock is changed, which forces all crtc's to be included to the state. This has been broken worse by adding in-fences support, which caused the double free to be done unconditionally. [IGT] kms_rotation_crc: starting subtest primary-rotation-180 ============================================================================= BUG kmalloc-128 (Tainted: G U ): Object already free ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in drm_atomic_helper_setup_commit+0x285/0x2f0 [drm_kms_helper] age=0 cpu=3 pid=1529 ___slab_alloc+0x308/0x3b0 __slab_alloc+0xd/0x20 kmem_cache_alloc_trace+0x92/0x1c0 drm_atomic_helper_setup_commit+0x285/0x2f0 [drm_kms_helper] intel_atomic_commit+0x35/0x4f0 [i915] drm_atomic_commit+0x46/0x50 [drm] drm_mode_atomic_ioctl+0x7d4/0xab0 [drm] drm_ioctl+0x2b3/0x490 [drm] do_vfs_ioctl+0x69c/0x700 SyS_ioctl+0x4e/0x80 entry_SYSCALL_64_fastpath+0x13/0x94 INFO: Freed in drm_event_cancel_free+0xa3/0xb0 [drm] age=0 cpu=3 pid=1529 __slab_free+0x48/0x2e0 kfree+0x159/0x1a0 drm_event_cancel_free+0xa3/0xb0 [drm] drm_mode_atomic_ioctl+0x86d/0xab0 [drm] drm_ioctl+0x2b3/0x490 [drm] do_vfs_ioctl+0x69c/0x700 SyS_ioctl+0x4e/0x80 entry_SYSCALL_64_fastpath+0x13/0x94 INFO: Slab 0xffffde1f0997b080 objects=17 used=2 fp=0xffff92fb65ec2578 flags=0x200000000008101 INFO: Object 0xffff92fb65ec2578 @offset=1400 fp=0xffff92fb65ec2ae8 Redzone ffff92fb65ec2570: bb bb bb bb bb bb bb bb ........ Object ffff92fb65ec2578: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec2588: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec2598: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25a8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25b8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25c8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25d8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25e8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. Redzone ffff92fb65ec25f8: bb bb bb bb bb bb bb bb ........ Padding ffff92fb65ec2738: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ CPU: 3 PID: 180 Comm: kworker/3:2 Tainted: G BU 4.10.0-rc6-patser+ #5039 Hardware name: /NUC5PPYB, BIOS PYBSWCEL.86A.0031.2015.0601.1712 06/01/2015 Workqueue: events intel_atomic_helper_free_state [i915] Call Trace: dump_stack+0x4d/0x6d print_trailer+0x20c/0x220 free_debug_processing+0x1c6/0x330 ? drm_atomic_state_default_clear+0xf7/0x1c0 [drm] __slab_free+0x48/0x2e0 ? drm_atomic_state_default_clear+0xf7/0x1c0 [drm] kfree+0x159/0x1a0 drm_atomic_state_default_clear+0xf7/0x1c0 [drm] ? drm_atomic_state_clear+0x30/0x30 [drm] intel_atomic_state_clear+0xd/0x20 [i915] drm_atomic_state_clear+0x1a/0x30 [drm] __drm_atomic_state_free+0x13/0x60 [drm] intel_atomic_helper_free_state+0x5d/0x70 [i915] process_one_work+0x260/0x4a0 worker_thread+0x2d1/0x4f0 kthread+0x127/0x130 ? process_one_work+0x4a0/0x4a0 ? kthread_stop+0x120/0x120 ret_from_fork+0x29/0x40 FIX kmalloc-128: Object at 0xffff92fb65ec2578 not freed Fixes: 3b24f7d67581 ("drm/atomic: Add struct drm_crtc_commit to track async updates") Fixes: 9626014258a5 ("drm/fence: add in-fences support") Cc: <stable@vger.kernel.org> # v4.8+ Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1485854725-27640-1-git-send-email-maarten.lankhorst@linux.intel.com
Diffstat (limited to 'kernel/softirq.c')