Hi! I've got the following report while fuzzing the kernel with syzkaller. On commit e19b205be43d11bff638cad4487008c48d21c103 (4.14-rc2). gadgetfs: bound to dummy_udc driver usb 1-1: new full-speed USB device number 2 using dummy_hcd gadgetfs: connected gadgetfs: disconnected gadgetfs: connected usb 1-1: config 3 has an invalid interface number: 220 but max is 0 usb 1-1: config 3 has an invalid interface number: 199 but max is 0 usb 1-1: config 3 has 2 interfaces, different from the descriptor's value: 1 usb 1-1: config 3 has no interface number 0 usb 1-1: config 3 has no interface number 1 usb 1-1: too many endpoints for config 3 interface 199 altsetting 74: 151, using maximum allowed: 30 usb 1-1: config 3 interface 199 altsetting 74 has 0 endpoint descriptors, different from the interface d escriptor's value: 151 usb 1-1: config 3 interface 199 has no altsetting 0 usb 1-1: New USB device found, idVendor=0841, idProduct=0001 usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0 gadgetfs: configuration #3 rio500 1-1:3.220: USB Rio found at address 2 rio500 1-1:3.199: USB Rio found at address 2 gadgetfs: disconnected usb 1-1: USB disconnect, device number 2 rio500 1-1:3.220: USB Rio disconnected. ================================================================== BUG: KASAN: double-free or invalid-free in disconnect_rio+0xef/0x200 CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.14.0-rc2-42660-g24b7bd59eec0 #277 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x292/0x395 lib/dump_stack.c:52 print_address_description+0x78/0x280 mm/kasan/report.c:252 kasan_report_double_free+0x5a/0x80 mm/kasan/report.c:333 kasan_slab_free+0xa4/0xc0 mm/kasan/kasan.c:514 slab_free_hook mm/slub.c:1390 slab_free_freelist_hook mm/slub.c:1412 slab_free mm/slub.c:2988 kfree+0xf6/0x2f0 mm/slub.c:3919 disconnect_rio+0xef/0x200 drivers/usb/misc/rio500.c:519 usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:861 device_release_driver_internal+0x4f4/0x5c0 drivers/base/dd.c:893 device_release_driver+0x1e/0x30 drivers/base/dd.c:918 bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565 device_del+0x5c4/0xab0 drivers/base/core.c:1985 usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170 usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124 hub_port_connect drivers/usb/core/hub.c:4754 hub_port_connect_change drivers/usb/core/hub.c:5009 port_event drivers/usb/core/hub.c:5115 hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195 process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119 worker_thread+0x221/0x1850 kernel/workqueue.c:2253 kthread+0x3a1/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Allocated by task 24: save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x11e/0x2d0 mm/slub.c:2772 kmalloc ./include/linux/slab.h:493 probe_rio+0x100/0x230 drivers/usb/misc/rio500.c:484 usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361 really_probe drivers/base/dd.c:413 driver_probe_device+0x610/0xa00 drivers/base/dd.c:557 __device_attach_driver+0x230/0x290 drivers/base/dd.c:653 bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463 __device_attach+0x26e/0x3d0 drivers/base/dd.c:710 device_initial_probe+0x1f/0x30 drivers/base/dd.c:757 bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523 device_add+0xd0b/0x1660 drivers/base/core.c:1835 usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932 generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174 usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266 really_probe drivers/base/dd.c:413 driver_probe_device+0x610/0xa00 drivers/base/dd.c:557 __device_attach_driver+0x230/0x290 drivers/base/dd.c:653 bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463 __device_attach+0x26e/0x3d0 drivers/base/dd.c:710 device_initial_probe+0x1f/0x30 drivers/base/dd.c:757 bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523 device_add+0xd0b/0x1660 drivers/base/core.c:1835 usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457 hub_port_connect drivers/usb/core/hub.c:4903 hub_port_connect_change drivers/usb/core/hub.c:5009 port_event drivers/usb/core/hub.c:5115 hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195 process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119 worker_thread+0x221/0x1850 kernel/workqueue.c:2253 kthread+0x3a1/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 Freed by task 24: save_stack_trace+0x1b/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:524 slab_free_hook mm/slub.c:1390 slab_free_freelist_hook mm/slub.c:1412 slab_free mm/slub.c:2988 kfree+0xf6/0x2f0 mm/slub.c:3919 disconnect_rio+0xef/0x200 drivers/usb/misc/rio500.c:519 usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:861 device_release_driver_internal+0x4f4/0x5c0 drivers/base/dd.c:893 device_release_driver+0x1e/0x30 drivers/base/dd.c:918 bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565 device_del+0x5c4/0xab0 drivers/base/core.c:1985 usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170 usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124 hub_port_connect drivers/usb/core/hub.c:4754 hub_port_connect_change drivers/usb/core/hub.c:5009 port_event drivers/usb/core/hub.c:5115 hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195 process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119 worker_thread+0x221/0x1850 kernel/workqueue.c:2253 kthread+0x3a1/0x470 kernel/kthread.c:231 ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 The buggy address belongs to the object at ffff88006a62c400 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 0 bytes inside of 4096-byte region [ffff88006a62c400, ffff88006a62d400) The buggy address belongs to the page: page:ffffea0001a98a00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x100000000008100(slab|head) raw: 0100000000008100 0000000000000000 0000000000000000 0000000100070007 raw: dead000000000100 dead000000000200 ffff88006c402c00 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88006a62c300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88006a62c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88006a62c400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88006a62c480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88006a62c500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at 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