================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic64_dec_if_positive include/asm-generic/atomic-instrumented.h:1176 [inline] BUG: KASAN: use-after-free in atomic_long_dec_if_positive include/asm-generic/atomic-long.h:515 [inline] BUG: KASAN: use-after-free in dec_ucount+0x54/0x130 kernel/ucount.c:249 Write of size 8 at addr ffff8880204f6240 by task kworker/u4:6/3126 CPU: 0 PID: 3126 Comm: kworker/u4:6 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic64_dec_if_positive include/asm-generic/atomic-instrumented.h:1176 [inline] atomic_long_dec_if_positive include/asm-generic/atomic-long.h:515 [inline] dec_ucount+0x54/0x130 kernel/ucount.c:249 dec_net_namespaces net/core/net_namespace.c:394 [inline] cleanup_net+0x6f3/0xb10 net/core/net_namespace.c:611 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 8462: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0x9b/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] alloc_ucounts+0x23d/0x5b0 kernel/ucount.c:170 set_cred_ucounts+0x171/0x3a0 kernel/cred.c:684 copy_creds+0x70e/0xb60 kernel/cred.c:375 copy_process+0x13c5/0x74d0 kernel/fork.c:1992 kernel_clone+0xe7/0xac0 kernel/fork.c:2509 __do_sys_clone+0xc8/0x110 kernel/fork.c:2626 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 8462: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kfree+0xe4/0x530 mm/slub.c:4264 put_ucounts+0x153/0x1c0 kernel/ucount.c:204 put_cred_rcu+0x27a/0x520 kernel/cred.c:124 rcu_do_batch kernel/rcu/tree.c:2550 [inline] rcu_core+0x7ab/0x1380 kernel/rcu/tree.c:2785 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 insert_work+0x48/0x370 kernel/workqueue.c:1332 __queue_work+0x5c1/0xed0 kernel/workqueue.c:1498 queue_work_on+0xee/0x110 kernel/workqueue.c:1525 queue_work include/linux/workqueue.h:507 [inline] call_usermodehelper_exec+0x1f0/0x4c0 kernel/umh.c:435 kobject_uevent_env+0xf8f/0x1650 lib/kobject_uevent.c:618 device_del+0x7eb/0xd40 drivers/base/core.c:3552 device_unregister+0x1f/0xc0 drivers/base/core.c:3575 device_destroy+0x96/0xd0 drivers/base/core.c:4121 vcs_remove_sysfs+0x1d/0x50 drivers/tty/vt/vc_screen.c:796 vc_deallocate+0x154/0x460 drivers/tty/vt/vt.c:1382 vt_disallocate drivers/tty/vt/vt_ioctl.c:637 [inline] vt_ioctl+0x25dc/0x2ac0 drivers/tty/vt/vt_ioctl.c:901 tty_ioctl+0xe4d/0x1600 drivers/tty/tty_io.c:2805 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Second to last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xe5/0x110 mm/kasan/generic.c:348 insert_work+0x48/0x370 kernel/workqueue.c:1332 __queue_work+0x5c1/0xed0 kernel/workqueue.c:1498 queue_work_on+0xee/0x110 kernel/workqueue.c:1525 queue_work include/linux/workqueue.h:507 [inline] call_usermodehelper_exec+0x1f0/0x4c0 kernel/umh.c:435 kobject_uevent_env+0xf8f/0x1650 lib/kobject_uevent.c:618 kobject_synth_uevent+0x701/0x850 lib/kobject_uevent.c:208 uevent_store+0x20/0x50 drivers/base/core.c:2372 dev_attr_store+0x50/0x80 drivers/base/core.c:2073 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x342/0x500 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write+0x426/0x650 fs/read_write.c:518 vfs_write+0x75a/0xa40 fs/read_write.c:605 ksys_write+0x12d/0x250 fs/read_write.c:658 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8880204f6200 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 64 bytes inside of 192-byte region [ffff8880204f6200, ffff8880204f62c0) The buggy address belongs to the page: page:ffffea0000813d80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880204f6500 pfn:0x204f6 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea000086bcc8 ffffea00005579c8 ffff888010841a00 raw: ffff8880204f6500 000000000010000f 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 11073167346, free_ts 9529355761 prep_new_page mm/page_alloc.c:2436 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4169 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5391 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2119 alloc_pages+0x238/0x2a0 mm/mempolicy.c:2242 alloc_slab_page mm/slub.c:1688 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1828 new_slab mm/slub.c:1891 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2800 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] slab_alloc mm/slub.c:2964 [inline] kmem_cache_alloc_trace+0x30f/0x3c0 mm/slub.c:2981 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] call_usermodehelper_setup+0x97/0x340 kernel/umh.c:365 kobject_uevent_env+0xf73/0x1650 lib/kobject_uevent.c:614 device_add+0xbc0/0x2180 drivers/base/core.c:3335 usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563 register_root_hub drivers/usb/core/hcd.c:1010 [inline] usb_add_hcd.cold+0x140c/0x1813 drivers/usb/core/hcd.c:2939 vhci_hcd_probe+0x1c9/0x3a0 drivers/usb/usbip/vhci_hcd.c:1374 platform_probe+0xfc/0x1f0 drivers/base/platform.c:1427 call_driver_probe drivers/base/dd.c:517 [inline] really_probe+0x23c/0xcd0 drivers/base/dd.c:595 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1346 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1397 free_unref_page_prepare mm/page_alloc.c:3332 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3411 __vunmap+0x783/0xb70 mm/vmalloc.c:2587 free_work+0x58/0x70 mm/vmalloc.c:82 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff8880204f6100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880204f6180: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880204f6200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880204f6280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880204f6300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================