================================================================== BUG: KASAN: use-after-free in io_poll_remove_all_table+0x161/0x2bd io_uring/poll.c:740 Read of size 8 at addr ffff888070848958 by task syz-executor.0/5603 CPU: 0 PID: 5603 Comm: syz-executor.0 Not tainted 6.2.0-rc3-next-20230112-syzkaller-dirty #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+0xc0/0xf0 mm/kasan/report.c:517 io_poll_remove_all_table+0x161/0x2bd io_uring/poll.c:740 io_poll_remove_all+0x2e/0x4b io_uring/poll.c:761 io_ring_ctx_wait_and_kill+0x1a0/0x340 io_uring/io_uring.c:3024 io_uring_release+0x46/0x4a io_uring/io_uring.c:3049 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb17/0x2a90 kernel/exit.c:867 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 get_signal+0x225f/0x24f0 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+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7efcf9a8c0c9 Code: Unable to access opcode bytes at 0x7efcf9a8c09f. RSP: 002b:00007efcfa823168 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffe00 RBX: 00007efcf9babf80 RCX: 00007efcf9a8c0c9 RDX: 0000000000002020 RSI: 00000000200021c0 RDI: 0000000000000006 RBP: 00007efcf9ae7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffdae1fefdf R14: 00007efcfa823300 R15: 0000000000022000 Allocated by task 5603: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:769 [inline] kmem_cache_alloc_bulk+0x3aa/0x730 mm/slub.c:4033 __io_alloc_req_refill+0xcc/0x40b io_uring/io_uring.c:1063 io_alloc_req_refill io_uring/io_uring.h:348 [inline] io_submit_sqes.cold+0x7c/0xc2 io_uring/io_uring.c:2413 __do_sys_io_uring_enter+0x9e4/0x2c10 io_uring/io_uring.c:3436 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 5603: 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:162 [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+0xec/0x4e0 mm/slub.c:3809 io_free_batch_list+0xdc/0x7d0 io_uring/io_uring.c:1466 __io_submit_flush_completions+0x4ea/0x940 io_uring/io_uring.c:1501 io_submit_flush_completions io_uring/io_uring.c:173 [inline] ctx_flush_and_put+0x13c/0x210 io_uring/io_uring.c:1145 tctx_task_work+0x1af/0x530 io_uring/io_uring.c:1236 task_work_run+0x16f/0x270 kernel/task_work.c:179 get_signal+0x1c7/0x24f0 kernel/signal.c:2635 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+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880708488c0 which belongs to the cache io_kiocb of size 224 The buggy address is located 152 bytes inside of 224-byte region [ffff8880708488c0, ffff8880708489a0) The buggy address belongs to the physical page: page:ffffea0001c21200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x70848 memcg:ffff888017e79781 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff8881463e0500 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800c000c 00000001ffffffff ffff888017e79781 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5603, tgid 5602 (syz-executor.0), ts 91825186400, free_ts 91803934935 prep_new_page mm/page_alloc.c:2549 [inline] get_page_from_freelist+0x11bb/0x2d50 mm/page_alloc.c:4324 __alloc_pages+0x1cb/0x5c0 mm/page_alloc.c:5590 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2281 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x350 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __kmem_cache_alloc_bulk mm/slub.c:3951 [inline] kmem_cache_alloc_bulk+0x23d/0x730 mm/slub.c:4026 __io_alloc_req_refill+0xcc/0x40b io_uring/io_uring.c:1063 io_alloc_req_refill io_uring/io_uring.h:348 [inline] io_submit_sqes.cold+0x7c/0xc2 io_uring/io_uring.c:2413 __do_sys_io_uring_enter+0x9e4/0x2c10 io_uring/io_uring.c:3436 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:1451 [inline] free_pcp_prepare+0x4d0/0x910 mm/page_alloc.c:1501 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page_list+0x176/0xcd0 mm/page_alloc.c:3528 release_pages+0xcb1/0x1330 mm/swap.c:1072 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:97 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline] tlb_flush_mmu mm/mmu_gather.c:299 [inline] tlb_finish_mmu+0x14b/0x7e0 mm/mmu_gather.c:391 exit_mmap+0x202/0x7c0 mm/mmap.c:3100 __mmput+0x128/0x4c0 kernel/fork.c:1212 mmput+0x60/0x70 kernel/fork.c:1234 exit_mm kernel/exit.c:563 [inline] do_exit+0x9ac/0x2a90 kernel/exit.c:854 do_group_exit+0xd4/0x2a0 kernel/exit.c:1012 __do_sys_exit_group kernel/exit.c:1023 [inline] __se_sys_exit_group kernel/exit.c:1021 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1021 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 Memory state around the buggy address: ffff888070848800: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff888070848880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff888070848900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888070848980: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff888070848a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================