Hello, syzbot found the following issue on: HEAD commit: 28157b8c USB: Better name for __check_usb_generic() git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing console output: https://syzkaller.appspot.com/x/log.txt?x=13a6a929900000 kernel config: https://syzkaller.appspot.com/x/.config?x=ccafc70ac3d5f49c dashboard link: https://syzkaller.appspot.com/bug?extid=59c4a4184685764d112a compiler: gcc (GCC) 10.1.0-syz 20200507 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+59c4a4184685764d112a@xxxxxxxxxxxxxxxxxxxxxxxxx au0828: recv_control_msg() Failed receiving control message, error -71. au8522_writereg: writereg error (reg == 0x106, val == 0x0001, ret == -5) ================================================================== BUG: KASAN: slab-out-of-bounds in i2c_adapter_id include/linux/i2c.h:902 [inline] BUG: KASAN: slab-out-of-bounds in mxl5007t_attach+0x2b6/0x2e0 drivers/media/tuners/mxl5007t.c:853 Read of size 4 at addr ffff8881d01247c8 by task kworker/0:3/136 CPU: 0 PID: 136 Comm: kworker/0:3 Not tainted 5.9.0-rc1-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+0xf6/0x16e lib/dump_stack.c:118 print_address_description.constprop.0+0x1c/0x210 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x37/0x7c mm/kasan/report.c:530 i2c_adapter_id include/linux/i2c.h:902 [inline] mxl5007t_attach+0x2b6/0x2e0 drivers/media/tuners/mxl5007t.c:853 au0828_dvb_register+0x451/0x1360 drivers/media/usb/au0828/au0828-dvb.c:597 au0828_usb_probe+0x56f/0x5d5 drivers/media/usb/au0828/au0828-core.c:738 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:374 really_probe+0x291/0xde0 drivers/base/dd.c:553 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:738 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:844 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4a0 drivers/base/dd.c:912 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xb51/0x1c70 drivers/base/core.c:2930 usb_set_configuration+0xf05/0x18a0 drivers/usb/core/message.c:2032 usb_generic_driver_probe+0xba/0xf2 drivers/usb/core/generic.c:239 usb_probe_device+0xd9/0x250 drivers/usb/core/driver.c:272 really_probe+0x291/0xde0 drivers/base/dd.c:553 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:738 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:844 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431 __device_attach+0x228/0x4a0 drivers/base/dd.c:912 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0xb51/0x1c70 drivers/base/core.c:2930 usb_new_device.cold+0x71d/0xfd4 drivers/usb/core/hub.c:2554 hub_port_connect drivers/usb/core/hub.c:5208 [inline] hub_port_connect_change drivers/usb/core/hub.c:5348 [inline] port_event drivers/usb/core/hub.c:5494 [inline] hub_event+0x2361/0x4390 drivers/usb/core/hub.c:5576 process_one_work+0x94c/0x15f0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x392/0x470 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Allocated by task 25209: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:666 [inline] ep_alloc.constprop.0+0xff/0x370 fs/eventpoll.c:1016 do_epoll_create+0x97/0x1c0 fs/eventpoll.c:2064 __do_sys_epoll_create1 fs/eventpoll.c:2095 [inline] __se_sys_epoll_create1 fs/eventpoll.c:2093 [inline] __x64_sys_epoll_create1+0x2d/0x40 fs/eventpoll.c:2093 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 25209: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xf3/0x130 mm/kasan/common.c:422 slab_free_hook mm/slub.c:1548 [inline] slab_free_freelist_hook+0x53/0x140 mm/slub.c:1581 slab_free mm/slub.c:3142 [inline] kfree+0xbe/0x470 mm/slub.c:4123 ep_eventpoll_release+0x41/0x60 fs/eventpoll.c:864 __fput+0x282/0x920 fs/file_table.c:281 task_work_run+0xdd/0x1a0 kernel/task_work.c:141 exit_task_work include/linux/task_work.h:25 [inline] do_exit+0xbaf/0x2890 kernel/exit.c:806 do_group_exit+0x125/0x310 kernel/exit.c:903 __do_sys_exit_group kernel/exit.c:914 [inline] __se_sys_exit_group kernel/exit.c:912 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:912 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881d0124400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 456 bytes to the right of 512-byte region [ffff8881d0124400, ffff8881d0124600) The buggy address belongs to the page: page:00000000182cf651 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8881d0124000 pfn:0x1d0124 head:00000000182cf651 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x200000000010200(slab|head) raw: 0200000000010200 ffffea0007296508 ffffea00074f9908 ffff8881da041280 raw: ffff8881d0124000 000000000010000d 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881d0124680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881d0124700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881d0124780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881d0124800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881d0124880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. 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