================================================================== BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:835 [inline] BUG: KASAN: use-after-free in hlist_del include/linux/list.h:852 [inline] BUG: KASAN: use-after-free in __cpuhp_state_remove_instance+0x58b/0x5b0 kernel/cpu.c:2002 Read of size 8 at addr ffff8880200d2598 by task syz-executor.1/10788 CPU: 3 PID: 10788 Comm: syz-executor.1 Not tainted 5.12.0-rc1-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0xfa/0x151 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2c6 mm/kasan/report.c:232 __kasan_report mm/kasan/report.c:399 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416 __hlist_del include/linux/list.h:835 [inline] hlist_del include/linux/list.h:852 [inline] __cpuhp_state_remove_instance+0x58b/0x5b0 kernel/cpu.c:2002 cpuhp_state_remove_instance_nocalls include/linux/cpuhotplug.h:407 [inline] io_wq_create+0x6ca/0xbf0 fs/io-wq.c:1056 io_init_wq_offload fs/io_uring.c:7792 [inline] io_uring_alloc_task_context+0x1bf/0x6a0 fs/io_uring.c:7811 io_uring_add_task_file+0x261/0x350 fs/io_uring.c:8773 io_uring_install_fd fs/io_uring.c:9381 [inline] io_uring_create fs/io_uring.c:9532 [inline] io_uring_setup+0x14c7/0x2be0 fs/io_uring.c:9571 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465f69 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2b4a827108 EFLAGS: 00000202 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465f69 RDX: 0000000020ffd000 RSI: 0000000020000240 RDI: 0000000000002de1 RBP: 0000000020000240 R08: 0000000020000140 R09: 0000000020000140 R10: 0000000020000100 R11: 0000000000000202 R12: 0000000020000140 R13: 0000000020ffd000 R14: 0000000020000100 R15: 0000000020002000 Allocated by task 10788: 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:427 [inline] ____kasan_kmalloc mm/kasan/common.c:506 [inline] ____kasan_kmalloc mm/kasan/common.c:465 [inline] __kasan_kmalloc+0x96/0xc0 mm/kasan/common.c:515 kasan_kmalloc include/linux/kasan.h:233 [inline] kmem_cache_alloc_trace+0x1ef/0x430 mm/slab.c:3570 kmalloc include/linux/slab.h:554 [inline] kzalloc include/linux/slab.h:684 [inline] io_wq_create+0xc0/0xbf0 fs/io-wq.c:1002 io_init_wq_offload fs/io_uring.c:7792 [inline] io_uring_alloc_task_context+0x1bf/0x6a0 fs/io_uring.c:7811 io_uring_add_task_file+0x261/0x350 fs/io_uring.c:8773 io_uring_install_fd fs/io_uring.c:9381 [inline] io_uring_create fs/io_uring.c:9532 [inline] io_uring_setup+0x14c7/0x2be0 fs/io_uring.c:9571 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 10788: 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:357 ____kasan_slab_free mm/kasan/common.c:360 [inline] ____kasan_slab_free mm/kasan/common.c:325 [inline] __kasan_slab_free+0xc7/0x100 mm/kasan/common.c:367 kasan_slab_free include/linux/kasan.h:199 [inline] __cache_free mm/slab.c:3440 [inline] kfree+0x104/0x2a0 mm/slab.c:3796 io_wq_destroy fs/io-wq.c:1091 [inline] io_wq_put+0x4d0/0x6d0 fs/io-wq.c:1098 io_wq_create+0x92d/0xbf0 fs/io-wq.c:1053 io_init_wq_offload fs/io_uring.c:7792 [inline] io_uring_alloc_task_context+0x1bf/0x6a0 fs/io_uring.c:7811 io_uring_add_task_file+0x261/0x350 fs/io_uring.c:8773 io_uring_install_fd fs/io_uring.c:9381 [inline] io_uring_create fs/io_uring.c:9532 [inline] io_uring_setup+0x14c7/0x2be0 fs/io_uring.c:9571 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xa4/0xd0 mm/kasan/generic.c:345 insert_work+0x48/0x370 kernel/workqueue.c:1331 __queue_work+0x5c1/0xf00 kernel/workqueue.c:1497 queue_work_on+0xae/0xc0 kernel/workqueue.c:1524 queue_work include/linux/workqueue.h:507 [inline] call_usermodehelper_exec+0x1f0/0x4c0 kernel/umh.c:433 kobject_uevent_env+0xf9f/0x1680 lib/kobject_uevent.c:617 __loop_clr_fd+0x662/0xff0 drivers/block/loop.c:1248 loop_clr_fd drivers/block/loop.c:1336 [inline] lo_ioctl+0x3b9/0x1620 drivers/block/loop.c:1694 blkdev_ioctl+0x2a1/0x6d0 block/ioctl.c:583 block_ioctl+0xf9/0x140 fs/block_dev.c:1658 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 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+0xa4/0xd0 mm/kasan/generic.c:345 insert_work+0x48/0x370 kernel/workqueue.c:1331 __queue_work+0x5c1/0xf00 kernel/workqueue.c:1497 queue_work_on+0xae/0xc0 kernel/workqueue.c:1524 queue_work include/linux/workqueue.h:507 [inline] call_usermodehelper_exec+0x1f0/0x4c0 kernel/umh.c:433 kobject_uevent_env+0xf9f/0x1680 lib/kobject_uevent.c:617 loop_configure+0x10cb/0x13a0 drivers/block/loop.c:255 lo_ioctl+0x3f7/0x1620 drivers/block/loop.c:1681 blkdev_ioctl+0x2a1/0x6d0 block/ioctl.c:583 block_ioctl+0xf9/0x140 fs/block_dev.c:1658 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8880200d2500 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 152 bytes inside of 192-byte region [ffff8880200d2500, ffff8880200d25c0) The buggy address belongs to the page: page:000000003d833db8 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880200d2400 pfn:0x200d2 flags: 0xfff00000000200(slab) raw: 00fff00000000200 ffffea00004f9a08 ffffea000076d948 ffff888010840000 raw: ffff8880200d2400 ffff8880200d2000 000000010000000f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880200d2480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880200d2500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880200d2580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8880200d2600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880200d2680: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================