================================================================== BUG: KASAN: use-after-free in atomic_fetch_sub include/asm-generic/atomic-instrumented.h:199 [inline] BUG: KASAN: use-after-free in refcount_sub_and_test include/linux/refcount.h:253 [inline] BUG: KASAN: use-after-free in refcount_dec_and_test include/linux/refcount.h:281 [inline] BUG: KASAN: use-after-free in kref_put include/linux/kref.h:64 [inline] BUG: KASAN: use-after-free in as102_release+0x58/0xd8 drivers/media/usb/as102/as102_usb_drv.c:458 Write of size 4 at addr ffff8881cd7b4140 by task syz-executor.3/10211 CPU: 0 PID: 10211 Comm: syz-executor.3 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xef/0x16e lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x314 mm/kasan/report.c:374 __kasan_report.cold+0x37/0x77 mm/kasan/report.c:506 kasan_report+0xe/0x20 mm/kasan/common.c:641 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x152/0x1c0 mm/kasan/generic.c:192 atomic_fetch_sub include/asm-generic/atomic-instrumented.h:199 [inline] refcount_sub_and_test include/linux/refcount.h:253 [inline] refcount_dec_and_test include/linux/refcount.h:281 [inline] kref_put include/linux/kref.h:64 [inline] as102_release+0x58/0xd8 drivers/media/usb/as102/as102_usb_drv.c:458 __fput+0x2d7/0x840 fs/file_table.c:280 task_work_run+0x13f/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x1d2/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x4e0/0x5a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x415fe1 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffc28f19170 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000415fe1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 0000000000000001 R08: 000000004f134a6b R09: 000000004f134a6f R10: 00007ffc28f19250 R11: 0000000000000293 R12: 000000000076bf20 R13: 0000000000770350 R14: 0000000000072bc3 R15: 000000000076bf2c Allocated by task 94: save_stack+0x1b/0x80 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:515 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:488 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] as102_usb_probe+0x4e/0x3d0 drivers/media/usb/as102/as102_usb_drv.c:350 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:361 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 usb_set_configuration+0xe47/0x17d0 drivers/usb/core/message.c:2023 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210 usb_probe_device+0xaf/0x140 drivers/usb/core/driver.c:266 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2538 hub_port_connect drivers/usb/core/hub.c:5185 [inline] hub_port_connect_change drivers/usb/core/hub.c:5325 [inline] port_event drivers/usb/core/hub.c:5471 [inline] hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5553 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Freed by task 94: save_stack+0x1b/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+0x117/0x160 mm/kasan/common.c:476 slab_free_hook mm/slub.c:1444 [inline] slab_free_freelist_hook mm/slub.c:1477 [inline] slab_free mm/slub.c:3024 [inline] kfree+0xd5/0x300 mm/slub.c:3976 as102_usb_probe.cold+0x142/0x3bf drivers/media/usb/as102/as102_usb_drv.c:412 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:361 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 usb_set_configuration+0xe47/0x17d0 drivers/usb/core/message.c:2023 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210 usb_probe_device+0xaf/0x140 drivers/usb/core/driver.c:266 really_probe+0x290/0xac0 drivers/base/dd.c:551 driver_probe_device+0x223/0x350 drivers/base/dd.c:724 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431 __device_attach+0x217/0x390 drivers/base/dd.c:897 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491 device_add+0x1459/0x1bf0 drivers/base/core.c:2487 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2538 hub_port_connect drivers/usb/core/hub.c:5185 [inline] hub_port_connect_change drivers/usb/core/hub.c:5325 [inline] port_event drivers/usb/core/hub.c:5471 [inline] hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5553 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264 process_scheduled_works kernel/workqueue.c:2326 [inline] worker_thread+0x7ab/0xe20 kernel/workqueue.c:2412 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8881cd7b4000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 320 bytes inside of 4096-byte region [ffff8881cd7b4000, ffff8881cd7b5000) The buggy address belongs to the page: page:ffffea000735ec00 refcount:1 mapcount:0 mapping:ffff8881da00c280 index:0x0 compound_mapcount: 0 flags: 0x200000000010200(slab|head) raw: 0200000000010200 dead000000000100 dead000000000122 ffff8881da00c280 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881cd7b4000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cd7b4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881cd7b4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881cd7b4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881cd7b4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================