================================================================== BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline] BUG: KASAN: slab-use-after-free in waitqueue_active include/linux/wait.h:129 [inline] BUG: KASAN: slab-use-after-free in wq_has_sleeper include/linux/wait.h:163 [inline] BUG: KASAN: slab-use-after-free in io_cqring_wake io_uring/io_uring.h:260 [inline] BUG: KASAN: slab-use-after-free in io_cq_unlock_post io_uring/io_uring.c:647 [inline] BUG: KASAN: slab-use-after-free in __io_req_complete_post+0x7a2/0x10b0 io_uring/io_uring.c:1012 Read of size 8 at addr ffff888144fa82d8 by task kworker/0:2/10846 CPU: 0 PID: 10846 Comm: kworker/0:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events ublk_stop_work_fn Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 list_empty include/linux/list.h:373 [inline] waitqueue_active include/linux/wait.h:129 [inline] wq_has_sleeper include/linux/wait.h:163 [inline] io_cqring_wake io_uring/io_uring.h:260 [inline] io_cq_unlock_post io_uring/io_uring.c:647 [inline] __io_req_complete_post+0x7a2/0x10b0 io_uring/io_uring.c:1012 io_uring_cmd_done+0x266/0x390 io_uring/uring_cmd.c:72 ublk_cancel_queue drivers/block/ublk_drv.c:1564 [inline] ublk_cancel_dev+0x1f7/0x3a0 drivers/block/ublk_drv.c:1577 ublk_stop_dev+0x367/0x410 drivers/block/ublk_drv.c:1678 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 11578: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] io_ring_ctx_alloc+0x54/0xc10 io_uring/io_uring.c:289 io_uring_create+0x2df/0x1330 io_uring/io_uring.c:3993 io_uring_setup io_uring/io_uring.c:4178 [inline] __do_sys_io_uring_setup io_uring/io_uring.c:4205 [inline] __se_sys_io_uring_setup+0x29f/0x2b0 io_uring/io_uring.c:4199 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 9555: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 io_ring_exit_work+0x7a6/0x830 io_uring/io_uring.c:3264 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 insert_work+0x3d/0x310 kernel/workqueue.c:1670 __queue_work+0xbfd/0xfd0 kernel/workqueue.c:1819 queue_work_on+0x128/0x1f0 kernel/workqueue.c:1854 queue_work include/linux/workqueue.h:562 [inline] io_ring_ctx_wait_and_kill+0x256/0x2b0 io_uring/io_uring.c:3296 io_uring_release+0x42/0x50 io_uring/io_uring.c:3304 __fput+0x221/0x930 fs/file_table.c:384 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x986/0x2530 kernel/exit.c:884 do_group_exit+0x22d/0x2f0 kernel/exit.c:1026 __do_sys_exit_group kernel/exit.c:1037 [inline] __se_sys_exit_group kernel/exit.c:1035 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1035 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888144fa8000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 728 bytes inside of freed 4096-byte region [ffff888144fa8000, ffff888144fa9000) The buggy address belongs to the physical page: page:ffffea000513ea00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x144fa8 head:ffffea000513ea00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x57ff00000000840(slab|head|node=1|zone=2|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 057ff00000000840 ffff888017c42140 ffffea0005286000 dead000000000002 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 18299792300, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2118 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] kobject_uevent_env+0x27c/0x890 lib/kobject_uevent.c:539 driver_register+0x2d4/0x310 drivers/base/driver.c:254 usb_register_driver+0x205/0x3c0 drivers/usb/core/driver.c:1062 do_one_initcall+0x242/0x790 init/main.c:1249 do_initcall_level+0x13d/0x1f0 init/main.c:1311 do_initcalls+0x69/0xd0 init/main.c:1327 kernel_init_freeable+0x3d9/0x560 init/main.c:1564 page_owner free stack trace missing Memory state around the buggy address: ffff888144fa8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888144fa8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888144fa8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888144fa8300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888144fa8380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================