================================================================== BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1ba/0x200 lib/list_debug.c:49 Read of size 8 at addr ffff88806092bcd0 by task syz.2.131/6541 CPU: 1 UID: 0 PID: 6541 Comm: syz.2.131 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 __list_del_entry_valid_or_report+0x1ba/0x200 lib/list_debug.c:49 __list_del_entry_valid include/linux/list.h:132 [inline] __list_del_entry include/linux/list.h:223 [inline] list_del_init include/linux/list.h:295 [inline] io_waitid_wait+0xf7/0x230 io_uring/waitid.c:239 __wake_up_common+0x132/0x1f0 kernel/sched/wait.c:108 __wake_up_common_lock kernel/sched/wait.c:125 [inline] __wake_up_sync_key+0x36/0x50 kernel/sched/wait.c:192 do_notify_parent_cldstop+0x540/0xb50 kernel/signal.c:2333 ptrace_stop.part.0+0x7e1/0x950 kernel/signal.c:2437 ptrace_stop kernel/signal.c:2376 [inline] ptrace_signal kernel/signal.c:2743 [inline] get_signal+0x13d5/0x26d0 kernel/signal.c:2921 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x419/0x4e0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f790d9c1785 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007f790bb03f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f790dbe6090 RCX: 00007f790d9c1785 RDX: 00007f790bb03fc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f790da11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007f790dbe6128 R14: 00007f790dbe6090 R15: 00007ffd97f38b08 Allocated by task 6533: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5603 [inline] __kmalloc_noprof+0x32f/0x880 mm/slub.c:5615 kmalloc_noprof include/linux/slab.h:961 [inline] io_uring_alloc_async_data io_uring/io_uring.h:328 [inline] io_waitid_prep+0x1aa/0x470 io_uring/waitid.c:251 io_init_req io_uring/io_uring.c:2248 [inline] io_submit_sqe io_uring/io_uring.c:2295 [inline] io_submit_sqes+0x855/0x2710 io_uring/io_uring.c:2447 __do_sys_io_uring_enter+0xd69/0x1630 io_uring/io_uring.c:3514 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6533: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2514 [inline] slab_free mm/slub.c:6566 [inline] kfree+0x2b8/0x6d0 mm/slub.c:6773 io_req_async_data_free io_uring/io_uring.h:349 [inline] io_waitid_free io_uring/waitid.c:40 [inline] io_waitid_finish io_uring/waitid.c:108 [inline] io_waitid_complete+0x249/0x5e0 io_uring/waitid.c:123 io_waitid_cb+0xe4/0x3a0 io_uring/waitid.c:217 io_handle_tw_list+0x483/0x500 io_uring/io_uring.c:1151 tctx_task_work_run+0xac/0x380 io_uring/io_uring.c:1216 tctx_task_work+0x7a/0xd0 io_uring/io_uring.c:1234 task_work_run+0x150/0x240 kernel/task_work.c:227 get_signal+0x1d0/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x419/0x4e0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88806092bc80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 80 bytes inside of freed 96-byte region [ffff88806092bc80, ffff88806092bce0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6092b flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b042280 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080200020 00000000f5000000 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6533, tgid 6532 (syz.2.131), ts 64929735651, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3030 [inline] allocate_slab mm/slub.c:3203 [inline] new_slab+0x24a/0x360 mm/slub.c:3257 ___slab_alloc+0xdc4/0x1ae0 mm/slub.c:4627 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4746 __slab_alloc_node mm/slub.c:4822 [inline] slab_alloc_node mm/slub.c:5233 [inline] __do_kmalloc_node mm/slub.c:5602 [inline] __kmalloc_noprof+0x501/0x880 mm/slub.c:5615 kmalloc_noprof include/linux/slab.h:961 [inline] io_uring_alloc_async_data io_uring/io_uring.h:328 [inline] io_waitid_prep+0x1aa/0x470 io_uring/waitid.c:251 io_init_req io_uring/io_uring.c:2248 [inline] io_submit_sqe io_uring/io_uring.c:2295 [inline] io_submit_sqes+0x855/0x2710 io_uring/io_uring.c:2447 __do_sys_io_uring_enter+0xd69/0x1630 io_uring/io_uring.c:3514 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page_owner free stack trace missing Memory state around the buggy address: ffff88806092bb80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc ffff88806092bc00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc >ffff88806092bc80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88806092bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806092bd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================