================================================================== BUG: KASAN: use-after-free in ax88172a_remove_mdio drivers/net/usb/ax88172a.c:112 [inline] BUG: KASAN: use-after-free in ax88172a_unbind+0x6f/0xdb drivers/net/usb/ax88172a.c:263 Read of size 8 at addr ffff8880a6ff9180 by task kworker/1:6/2675 CPU: 1 PID: 2675 Comm: kworker/1:6 Not tainted 5.6.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x128/0x182 lib/dump_stack.c:118 print_address_description.constprop.8.cold.10+0x9/0x317 mm/kasan/report.c:374 __kasan_report.cold.11+0x1c/0x34 mm/kasan/report.c:506 kasan_report+0xe/0x20 mm/kasan/common.c:641 ax88172a_remove_mdio drivers/net/usb/ax88172a.c:112 [inline] ax88172a_unbind+0x6f/0xdb drivers/net/usb/ax88172a.c:263 usbnet_disconnect+0x128/0x260 drivers/net/usb/usbnet.c:1618 usb_unbind_interface+0x15c/0x870 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1137 [inline] device_release_driver_internal+0x1d2/0x470 drivers/base/dd.c:1168 bus_remove_device+0x293/0x460 drivers/base/bus.c:533 device_del+0x421/0xc00 drivers/base/core.c:2677 usb_disable_device+0x1ae/0x580 drivers/usb/core/message.c:1237 usb_disconnect+0x227/0x850 drivers/usb/core/hub.c:2211 hub_port_connect drivers/usb/core/hub.c:5046 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x1048/0x2d60 drivers/usb/core/hub.c:5563 process_one_work+0x903/0x15c0 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x5aa/0xb50 kernel/workqueue.c:2412 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 2675: save_stack+0x19/0x80 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc.constprop.17+0xc1/0xd0 mm/kasan/common.c:515 kmem_cache_alloc_trace+0x156/0x780 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] ax88172a_bind+0x94/0x708 drivers/net/usb/ax88172a.c:180 usbnet_probe+0xabb/0x2260 drivers/net/usb/usbnet.c:1737 usb_probe_interface+0x268/0x6c0 drivers/usb/core/driver.c:361 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 usb_set_configuration+0xc02/0x1560 drivers/usb/core/message.c:2023 generic_probe+0x61/0x8a drivers/usb/core/generic.c:210 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 usb_new_device.cold.66+0x679/0xe85 drivers/usb/core/hub.c:2548 hub_port_connect drivers/usb/core/hub.c:5195 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x15fe/0x2d60 drivers/usb/core/hub.c:5563 process_one_work+0x903/0x15c0 kernel/workqueue.c:2264 worker_thread+0x82/0xb50 kernel/workqueue.c:2410 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Freed by task 2675: save_stack+0x19/0x80 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:337 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:476 __cache_free mm/slab.c:3426 [inline] kfree+0x107/0x2b0 mm/slab.c:3757 ax88172a_bind.cold.6+0x94/0x206 drivers/net/usb/ax88172a.c:239 usbnet_probe+0xabb/0x2260 drivers/net/usb/usbnet.c:1737 usb_probe_interface+0x268/0x6c0 drivers/usb/core/driver.c:361 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 usb_set_configuration+0xc02/0x1560 drivers/usb/core/message.c:2023 generic_probe+0x61/0x8a drivers/usb/core/generic.c:210 really_probe+0x1f9/0x5e0 drivers/base/dd.c:551 driver_probe_device+0xc9/0x1b0 drivers/base/dd.c:724 bus_for_each_drv+0x117/0x1a0 drivers/base/bus.c:431 __device_attach+0x1be/0x2c0 drivers/base/dd.c:897 bus_probe_device+0x19e/0x250 drivers/base/bus.c:491 device_add+0x10d0/0x1900 drivers/base/core.c:2500 usb_new_device.cold.66+0x679/0xe85 drivers/usb/core/hub.c:2548 hub_port_connect drivers/usb/core/hub.c:5195 [inline] hub_port_connect_change drivers/usb/core/hub.c:5335 [inline] port_event drivers/usb/core/hub.c:5481 [inline] hub_event+0x15fe/0x2d60 drivers/usb/core/hub.c:5563 process_one_work+0x903/0x15c0 kernel/workqueue.c:2264 worker_thread+0x82/0xb50 kernel/workqueue.c:2410 kthread+0x31d/0x3e0 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8880a6ff9180 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 0 bytes inside of 64-byte region [ffff8880a6ff9180, ffff8880a6ff91c0) The buggy address belongs to the page: page:ffffea00029bfe40 refcount:1 mapcount:0 mapping:ffff8880aa400380 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00028839c8 ffffea0002926708 ffff8880aa400380 raw: 0000000000000000 ffff8880a6ff9000 0000000100000020 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a6ff9080: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff8880a6ff9100: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc >ffff8880a6ff9180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8880a6ff9200: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff8880a6ff9280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================