================================================================== BUG: KASAN: use-after-free in io_wq_worker_running+0x114/0x130 io_uring/io-wq.c:674 Read of size 4 at addr ffff88807e40d404 by task iou-wrk-27354/27405 CPU: 0 PID: 27405 Comm: iou-wrk-27354 Not tainted 6.2.0-rc3-syzkaller-00021-g7dd4b804e080 #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/0x461 mm/kasan/report.c:417 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517 io_wq_worker_running+0x114/0x130 io_uring/io-wq.c:674 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 Allocated by task 27354: 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+0xa3/0xb0 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 27405: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] __cache_free mm/slab.c:3394 [inline] __do_kmem_cache_free mm/slab.c:3580 [inline] __kmem_cache_free+0xcd/0x3b0 mm/slab.c:3587 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+0x7b/0x90 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 Second to last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0x7b/0x90 mm/kasan/generic.c:488 kvfree_call_rcu+0x78/0x8f0 kernel/rcu/tree.c:3376 io_worker_exit io_uring/io-wq.c:237 [inline] io_wqe_worker+0x9e6/0xe40 io_uring/io-wq.c:661 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff88807e40d400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 4 bytes inside of 512-byte region [ffff88807e40d400, ffff88807e40d600) The buggy address belongs to the physical page: page:ffffea0001f90340 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e40d flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff888012440600 ffffea0001aa6890 ffffea000065f7d0 raw: 0000000000000000 ffff88807e40d000 0000000100000004 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 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 23111, tgid 23100 (syz-executor.0), ts 461254289402, free_ts 461250581042 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] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x94/0x390 mm/slab.c:2574 cache_alloc_refill+0x27f/0x380 mm/slab.c:2947 ____cache_alloc mm/slab.c:3023 [inline] ____cache_alloc mm/slab.c:3006 [inline] __do_cache_alloc mm/slab.c:3209 [inline] slab_alloc_node mm/slab.c:3254 [inline] __kmem_cache_alloc_node+0x478/0x510 mm/slab.c:3544 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 kasan_depopulate_vmalloc_pte+0x60/0x80 mm/kasan/shadow.c:372 apply_to_pte_range mm/memory.c:2600 [inline] apply_to_pmd_range mm/memory.c:2644 [inline] apply_to_pud_range mm/memory.c:2680 [inline] apply_to_p4d_range mm/memory.c:2716 [inline] __apply_to_page_range+0x68c/0x1030 mm/memory.c:2750 kasan_release_vmalloc+0xab/0xc0 mm/kasan/shadow.c:486 __purge_vmap_area_lazy+0x897/0x1f80 mm/vmalloc.c:1776 drain_vmap_area_work+0x56/0xe0 mm/vmalloc.c:1809 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: ffff88807e40d300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e40d380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807e40d400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e40d480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e40d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================