================================================================== BUG: KASAN: use-after-free in io_wq_worker_wake+0xa8/0xb0 io_uring/io-wq.c:862 Read of size 8 at addr ffff88801cdd7028 by task syz-executor318/18434 CPU: 1 PID: 18434 Comm: syz-executor318 Not tainted 6.2.0-rc3-syzkaller-00008-g1fe4fd6f5cad #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x15e/0x45d mm/kasan/report.c:417 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517 io_wq_worker_wake+0xa8/0xb0 io_uring/io-wq.c:862 io_wq_for_each_worker io_uring/io-wq.c:849 [inline] io_wq_exit_workers io_uring/io-wq.c:1250 [inline] io_wq_put_and_exit+0x52a/0xe30 io_uring/io-wq.c:1289 io_uring_clean_tctx+0x117/0x178 io_uring/tctx.c:193 io_uring_cancel_generic+0x5ae/0x606 io_uring/io_uring.c:3145 io_uring_files_cancel include/linux/io_uring.h:55 [inline] do_exit+0x522/0x2950 kernel/exit.c:822 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 get_signal+0x21c3/0x2450 kernel/signal.c:2859 arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fbc7f2cbb99 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbc7f27d2e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002ff RBX: 00007fbc7f353428 RCX: 00007fbc7f2cbb99 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007fbc7f353420 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbc7f35342c R13: 00007fbc7f321074 R14: 8000000000000001 R15: 0000000000000003 Allocated by task 18434: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0xa5/0xb0 mm/kasan/common.c:380 kmalloc_node include/linux/slab.h:606 [inline] kzalloc_node include/linux/slab.h:731 [inline] create_io_worker+0x10c/0x630 io_uring/io-wq.c:801 io_wqe_create_worker io_uring/io-wq.c:310 [inline] io_wqe_enqueue+0x6c3/0xbc0 io_uring/io-wq.c:936 io_queue_iowq+0x282/0x5c0 io_uring/io_uring.c:475 io_queue_sqe_fallback+0xf3/0x190 io_uring/io_uring.c:2059 io_submit_sqe io_uring/io_uring.c:2281 [inline] io_submit_sqes+0x11db/0x1e60 io_uring/io_uring.c:2397 __do_sys_io_uring_enter+0xc1d/0x2540 io_uring/io_uring.c:3345 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 18437: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0xaf/0x3b0 mm/slub.c:3800 io_wq_cancel_tw_create io_uring/io-wq.c:1233 [inline] io_queue_worker_create+0x567/0x660 io_uring/io-wq.c:381 io_wqe_dec_running+0x1e4/0x240 io_uring/io-wq.c:410 io_wq_worker_sleeping+0xa6/0xc0 io_uring/io-wq.c:698 sched_submit_work kernel/sched/core.c:6597 [inline] schedule+0x16e/0x1b0 kernel/sched/core.c:6628 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6690 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa48/0x1360 kernel/locking/mutex.c:747 io_ring_submit_lock io_uring/io_uring.h:215 [inline] io_file_get_fixed io_uring/io_uring.c:1966 [inline] io_assign_file io_uring/io_uring.c:1834 [inline] io_assign_file io_uring/io_uring.c:1828 [inline] io_wq_submit_work+0x5f7/0xdc0 io_uring/io_uring.c:1916 io_worker_handle_work+0xc41/0x1c60 io_uring/io-wq.c:587 io_wqe_worker+0xa5b/0xe40 io_uring/io-wq.c:632 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:488 task_work_add+0x7f/0x2c0 kernel/task_work.c:48 io_queue_worker_create+0x41d/0x660 io_uring/io-wq.c:373 io_wqe_dec_running+0x1e4/0x240 io_uring/io-wq.c:410 io_wq_worker_sleeping+0xa6/0xc0 io_uring/io-wq.c:698 sched_submit_work kernel/sched/core.c:6597 [inline] schedule+0x16e/0x1b0 kernel/sched/core.c:6628 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6690 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0xa48/0x1360 kernel/locking/mutex.c:747 io_ring_submit_lock io_uring/io_uring.h:215 [inline] io_file_get_fixed io_uring/io_uring.c:1966 [inline] io_assign_file io_uring/io_uring.c:1834 [inline] io_assign_file io_uring/io_uring.c:1828 [inline] io_wq_submit_work+0x5f7/0xdc0 io_uring/io_uring.c:1916 io_worker_handle_work+0xc41/0x1c60 io_uring/io-wq.c:587 io_wqe_worker+0xa5b/0xe40 io_uring/io-wq.c:632 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff88801cdd7000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 40 bytes inside of 512-byte region [ffff88801cdd7000, ffff88801cdd7200) The buggy address belongs to the physical page: page:ffffea0000737500 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1cdd4 head:ffffea0000737500 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888012441c80 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 18245, tgid 18244 (syz-executor318), ts 59882596706, free_ts 59723498525 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5549 __alloc_pages_node include/linux/gfp.h:237 [inline] alloc_slab_page mm/slub.c:1853 [inline] allocate_slab+0xa7/0x350 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] __kmem_cache_alloc_node+0x1a4/0x430 mm/slub.c:3491 kmalloc_node_trace+0x21/0x60 mm/slab_common.c:1075 kmalloc_node include/linux/slab.h:606 [inline] kzalloc_node include/linux/slab.h:731 [inline] create_io_worker+0x10c/0x630 io_uring/io-wq.c:801 io_wqe_create_worker io_uring/io-wq.c:310 [inline] io_wqe_enqueue+0x6c3/0xbc0 io_uring/io-wq.c:936 io_queue_iowq+0x282/0x5c0 io_uring/io_uring.c:475 io_queue_sqe_fallback+0xf3/0x190 io_uring/io_uring.c:2059 io_submit_sqe io_uring/io_uring.c:2281 [inline] io_submit_sqes+0x11db/0x1e60 io_uring/io_uring.c:2397 __do_sys_io_uring_enter+0xc1d/0x2540 io_uring/io_uring.c:3345 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare+0x65c/0xc00 mm/page_alloc.c:1496 free_unref_page_prepare mm/page_alloc.c:3369 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3464 __vunmap+0x85d/0xd30 mm/vmalloc.c:2727 free_work+0x5c/0x80 mm/vmalloc.c:100 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Memory state around the buggy address: ffff88801cdd6f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801cdd6f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801cdd7000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801cdd7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801cdd7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================