================================================================== BUG: KASAN: double-free or invalid-free in slab_free syzkaller/managers/android-5-10/kernel/mm/slub.c:3204 [inline] BUG: KASAN: double-free or invalid-free in kfree+0xd5/0x320 syzkaller/managers/android-5-10/kernel/mm/slub.c:4192 CPU: 0 PID: 23973 Comm: io_wq_manager Not tainted 5.10.76-syzkaller-01178-g4944ec82ebb9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack syzkaller/managers/android-5-10/kernel/lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b syzkaller/managers/android-5-10/kernel/lib/dump_stack.c:118 print_address_description+0x8d/0x3d0 syzkaller/managers/android-5-10/kernel/mm/kasan/report.c:233 kasan_report_invalid_free+0x58/0x130 syzkaller/managers/android-5-10/kernel/mm/kasan/report.c:358 ____kasan_slab_free+0x14b/0x170 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:368 kasan_slab_free syzkaller/managers/android-5-10/kernel/./include/linux/kasan.h:235 [inline] slab_free_hook syzkaller/managers/android-5-10/kernel/mm/slub.c:1596 [inline] slab_free_freelist_hook+0xcc/0x1a0 syzkaller/managers/android-5-10/kernel/mm/slub.c:1622 slab_free syzkaller/managers/android-5-10/kernel/mm/slub.c:3204 [inline] kfree+0xd5/0x320 syzkaller/managers/android-5-10/kernel/mm/slub.c:4192 __io_queue_deferred syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1541 [inline] io_commit_cqring+0x76a/0xa00 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1587 __io_req_task_cancel+0x64/0x720 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2065 io_req_task_cancel+0x51/0x130 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2078 task_work_run+0x147/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:154 io_wq_manager+0x1aa/0x8b0 syzkaller/managers/android-5-10/kernel/fs/io-wq.c:797 kthread+0x371/0x390 syzkaller/managers/android-5-10/kernel/kernel/kthread.c:313 ret_from_fork+0x1f/0x30 syzkaller/managers/android-5-10/kernel/arch/x86/entry/entry_64.S:296 Allocated by task 23972: kasan_save_stack syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:38 [inline] kasan_set_track syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:46 [inline] set_alloc_info syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:428 [inline] ____kasan_kmalloc+0xdc/0x110 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:507 __kasan_kmalloc+0x9/0x10 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:516 kasan_kmalloc syzkaller/managers/android-5-10/kernel/./include/linux/kasan.h:269 [inline] kmem_cache_alloc_trace+0x210/0x3a0 syzkaller/managers/android-5-10/kernel/mm/slub.c:2975 kmalloc syzkaller/managers/android-5-10/kernel/./include/linux/slab.h:552 [inline] io_req_defer+0x40e/0x11b0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:5921 io_queue_sqe+0x2a/0x1180 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:6397 io_submit_sqe+0x385/0xfd0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:6487 io_submit_sqes+0x1050/0x2da0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:6715 __do_sys_io_uring_enter syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9110 [inline] __se_sys_io_uring_enter+0x322/0x12b0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9052 __x64_sys_io_uring_enter+0xe5/0x100 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9052 do_syscall_64+0x31/0x70 syzkaller/managers/android-5-10/kernel/arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88810da021c0 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff88810da021c0, ffff88810da021e0) The buggy address belongs to the page: page:ffffea0004368080 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88810da021c0 pfn:0x10da02 flags: 0x8000000000000200(slab) raw: 8000000000000200 0000000000000000 0000000100000001 ffff888100043980 raw: ffff88810da021c0 0000000080400020 00000001ffffffff 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 287, ts 12212385617, free_ts 12212299755 set_page_owner syzkaller/managers/android-5-10/kernel/./include/linux/page_owner.h:35 [inline] post_alloc_hook syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:2385 [inline] prep_new_page syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:2391 [inline] get_page_from_freelist+0xa74/0xa90 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:4063 __alloc_pages_nodemask+0x3c8/0x820 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:5106 alloc_slab_page syzkaller/managers/android-5-10/kernel/mm/slub.c:1807 [inline] allocate_slab+0x6b/0x350 syzkaller/managers/android-5-10/kernel/mm/slub.c:1809 new_slab syzkaller/managers/android-5-10/kernel/mm/slub.c:1870 [inline] new_slab_objects syzkaller/managers/android-5-10/kernel/mm/slub.c:2629 [inline] ___slab_alloc+0x143/0x2f0 syzkaller/managers/android-5-10/kernel/mm/slub.c:2792 __slab_alloc syzkaller/managers/android-5-10/kernel/mm/slub.c:2832 [inline] slab_alloc_node syzkaller/managers/android-5-10/kernel/mm/slub.c:2914 [inline] slab_alloc syzkaller/managers/android-5-10/kernel/mm/slub.c:2956 [inline] __kmalloc+0x2af/0x3d0 syzkaller/managers/android-5-10/kernel/mm/slub.c:4030 kmalloc syzkaller/managers/android-5-10/kernel/./include/linux/slab.h:557 [inline] kzalloc+0x21/0x30 syzkaller/managers/android-5-10/kernel/./include/linux/slab.h:664 lsm_cred_alloc syzkaller/managers/android-5-10/kernel/security/security.c:500 [inline] security_prepare_creds+0x40/0x270 syzkaller/managers/android-5-10/kernel/security/security.c:1607 prepare_creds+0x3f7/0x5e0 syzkaller/managers/android-5-10/kernel/kernel/cred.c:288 set_current_groups syzkaller/managers/android-5-10/kernel/kernel/groups.c:143 [inline] __do_sys_setgroups syzkaller/managers/android-5-10/kernel/kernel/groups.c:210 [inline] __se_sys_setgroups+0x2af/0x420 syzkaller/managers/android-5-10/kernel/kernel/groups.c:190 __x64_sys_setgroups+0x5b/0x70 syzkaller/managers/android-5-10/kernel/kernel/groups.c:190 do_syscall_64+0x31/0x70 syzkaller/managers/android-5-10/kernel/arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 page last free stack trace: reset_page_owner syzkaller/managers/android-5-10/kernel/./include/linux/page_owner.h:28 [inline] free_pages_prepare syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:1331 [inline] free_pcp_prepare+0x18f/0x1c0 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:1405 free_unref_page_prepare syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:3291 [inline] free_unref_page syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:3341 [inline] free_the_page syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:5165 [inline] __free_pages+0x2e3/0x4a0 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:5173 free_pages+0x7c/0x90 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:5184 kasan_depopulate_vmalloc_pte+0x6a/0x90 syzkaller/managers/android-5-10/kernel/mm/kasan/shadow.c:369 apply_to_pte_range syzkaller/managers/android-5-10/kernel/mm/memory.c:2462 [inline] apply_to_pmd_range syzkaller/managers/android-5-10/kernel/mm/memory.c:2498 [inline] apply_to_pud_range syzkaller/managers/android-5-10/kernel/mm/memory.c:2526 [inline] apply_to_p4d_range syzkaller/managers/android-5-10/kernel/mm/memory.c:2554 [inline] __apply_to_page_range+0x7f5/0xa10 syzkaller/managers/android-5-10/kernel/mm/memory.c:2581 apply_to_existing_page_range+0x38/0x50 syzkaller/managers/android-5-10/kernel/mm/memory.c:2830 kasan_release_vmalloc+0x9a/0xb0 syzkaller/managers/android-5-10/kernel/mm/kasan/shadow.c:479 __purge_vmap_area_lazy+0x13f0/0x1510 syzkaller/managers/android-5-10/kernel/mm/vmalloc.c:1374 _vm_unmap_aliases+0x354/0x3d0 syzkaller/managers/android-5-10/kernel/mm/vmalloc.c:1771 vm_unmap_aliases+0x19/0x20 syzkaller/managers/android-5-10/kernel/mm/vmalloc.c:1794 change_page_attr_set_clr+0x2ae/0x6a0 syzkaller/managers/android-5-10/kernel/arch/x86/mm/pat/set_memory.c:1732 change_page_attr_clear syzkaller/managers/android-5-10/kernel/arch/x86/mm/pat/set_memory.c:1789 [inline] set_memory_ro+0xa4/0xe0 syzkaller/managers/android-5-10/kernel/arch/x86/mm/pat/set_memory.c:1935 bpf_jit_binary_lock_ro syzkaller/managers/android-5-10/kernel/./include/linux/filter.h:839 [inline] bpf_int_jit_compile+0x9b1e/0x9fd0 syzkaller/managers/android-5-10/kernel/arch/x86/net/bpf_jit_comp.c:2155 bpf_prog_select_runtime+0x6c3/0x990 syzkaller/managers/android-5-10/kernel/kernel/bpf/core.c:1863 bpf_migrate_filter syzkaller/managers/android-5-10/kernel/net/core/filter.c:1294 [inline] bpf_prepare_filter+0x102c/0x1360 syzkaller/managers/android-5-10/kernel/net/core/filter.c:1342 __get_filter+0x2fd/0x430 syzkaller/managers/android-5-10/kernel/net/core/filter.c:1511 Memory state around the buggy address: ffff88810da02080: 00 00 00 00 fc fc fc fc fb fb fb fb fc fc fc fc ffff88810da02100: 00 00 01 fc fc fc fc fc fb fb fb fb fc fc fc fc >ffff88810da02180: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff88810da02200: fb fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ffff88810da02280: fb fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc ================================================================== ================================================================== BUG: KASAN: use-after-free in task_work_run+0x126/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:153 Read of size 8 at addr ffff88814d603958 by task io_wq_manager/23973 CPU: 0 PID: 23973 Comm: io_wq_manager Tainted: G B 5.10.76-syzkaller-01178-g4944ec82ebb9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack syzkaller/managers/android-5-10/kernel/lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b syzkaller/managers/android-5-10/kernel/lib/dump_stack.c:118 print_address_description+0x8d/0x3d0 syzkaller/managers/android-5-10/kernel/mm/kasan/report.c:233 __kasan_report+0x142/0x220 syzkaller/managers/android-5-10/kernel/mm/kasan/report.c:419 kasan_report+0x51/0x70 syzkaller/managers/android-5-10/kernel/mm/kasan/report.c:436 __asan_report_load8_noabort+0x14/0x20 syzkaller/managers/android-5-10/kernel/mm/kasan/report_generic.c:309 task_work_run+0x126/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:153 io_wq_manager+0x1aa/0x8b0 syzkaller/managers/android-5-10/kernel/fs/io-wq.c:797 kthread+0x371/0x390 syzkaller/managers/android-5-10/kernel/kernel/kthread.c:313 ret_from_fork+0x1f/0x30 syzkaller/managers/android-5-10/kernel/arch/x86/entry/entry_64.S:296 Allocated by task 23972: kasan_save_stack syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:38 [inline] kasan_set_track syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:46 [inline] set_alloc_info syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:428 [inline] __kasan_slab_alloc+0xb2/0xe0 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:461 kasan_slab_alloc syzkaller/managers/android-5-10/kernel/./include/linux/kasan.h:259 [inline] slab_post_alloc_hook syzkaller/managers/android-5-10/kernel/mm/slab.h:583 [inline] kmem_cache_alloc_bulk+0x2d5/0x3f0 syzkaller/managers/android-5-10/kernel/mm/slub.c:3406 io_alloc_req syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1857 [inline] io_submit_sqes+0x6bf/0x2da0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:6695 __do_sys_io_uring_enter syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9110 [inline] __se_sys_io_uring_enter+0x322/0x12b0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9052 __x64_sys_io_uring_enter+0xe5/0x100 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9052 do_syscall_64+0x31/0x70 syzkaller/managers/android-5-10/kernel/arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 23973: kasan_save_stack syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x80 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:46 kasan_set_free_info+0x23/0x40 syzkaller/managers/android-5-10/kernel/mm/kasan/generic.c:357 ____kasan_slab_free+0x133/0x170 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:360 __kasan_slab_free+0x11/0x20 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:368 kasan_slab_free syzkaller/managers/android-5-10/kernel/./include/linux/kasan.h:235 [inline] slab_free_hook syzkaller/managers/android-5-10/kernel/mm/slub.c:1596 [inline] slab_free_freelist_hook+0xcc/0x1a0 syzkaller/managers/android-5-10/kernel/mm/slub.c:1622 slab_free syzkaller/managers/android-5-10/kernel/mm/slub.c:3204 [inline] kmem_cache_free+0xb5/0x1f0 syzkaller/managers/android-5-10/kernel/mm/slub.c:3220 __io_free_req+0x20e/0x380 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1912 io_free_req syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2135 [inline] io_double_put_req syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2275 [inline] __io_req_task_cancel+0x144/0x720 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2070 io_req_task_cancel+0x51/0x130 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2078 task_work_run+0x147/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:154 io_wq_manager+0x1aa/0x8b0 syzkaller/managers/android-5-10/kernel/fs/io-wq.c:797 kthread+0x371/0x390 syzkaller/managers/android-5-10/kernel/kernel/kthread.c:313 ret_from_fork+0x1f/0x30 syzkaller/managers/android-5-10/kernel/arch/x86/entry/entry_64.S:296 Last potentially related work creation: kasan_save_stack+0x36/0x60 syzkaller/managers/android-5-10/kernel/mm/kasan/common.c:38 kasan_record_aux_stack+0xd3/0xf0 syzkaller/managers/android-5-10/kernel/mm/kasan/generic.c:345 task_work_add+0xa7/0x320 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:39 io_req_task_queue syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2119 [inline] __io_queue_deferred syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1540 [inline] io_commit_cqring+0x756/0xa00 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1587 __io_req_task_cancel+0x64/0x720 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2065 io_req_task_cancel+0x51/0x130 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2078 task_work_run+0x147/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:154 io_wq_manager+0x1aa/0x8b0 syzkaller/managers/android-5-10/kernel/fs/io-wq.c:797 kthread+0x371/0x390 syzkaller/managers/android-5-10/kernel/kernel/kthread.c:313 ret_from_fork+0x1f/0x30 syzkaller/managers/android-5-10/kernel/arch/x86/entry/entry_64.S:296 The buggy address belongs to the object at ffff88814d6038c0 which belongs to the cache io_kiocb of size 216 The buggy address is located 152 bytes inside of 216-byte region [ffff88814d6038c0, ffff88814d603998) The buggy address belongs to the page: page:ffffea00053580c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88814d603c80 pfn:0x14d603 flags: 0x8000000000000200(slab) raw: 8000000000000200 0000000000000000 0000000100000001 ffff888103fc6f00 raw: ffff88814d603c80 00000000800c000a 00000001ffffffff 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 21935, ts 1353047181205, free_ts 1353021242919 set_page_owner syzkaller/managers/android-5-10/kernel/./include/linux/page_owner.h:35 [inline] post_alloc_hook syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:2385 [inline] prep_new_page syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:2391 [inline] get_page_from_freelist+0xa74/0xa90 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:4063 __alloc_pages_nodemask+0x3c8/0x820 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:5106 alloc_slab_page syzkaller/managers/android-5-10/kernel/mm/slub.c:1807 [inline] allocate_slab+0x6b/0x350 syzkaller/managers/android-5-10/kernel/mm/slub.c:1809 new_slab syzkaller/managers/android-5-10/kernel/mm/slub.c:1870 [inline] new_slab_objects syzkaller/managers/android-5-10/kernel/mm/slub.c:2629 [inline] ___slab_alloc+0x143/0x2f0 syzkaller/managers/android-5-10/kernel/mm/slub.c:2792 kmem_cache_alloc_bulk+0x167/0x3f0 syzkaller/managers/android-5-10/kernel/mm/slub.c:3385 io_alloc_req syzkaller/managers/android-5-10/kernel/fs/io_uring.c:1857 [inline] io_submit_sqes+0x6bf/0x2da0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:6695 __do_sys_io_uring_enter syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9110 [inline] __se_sys_io_uring_enter+0x322/0x12b0 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9052 __x64_sys_io_uring_enter+0xe5/0x100 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:9052 do_syscall_64+0x31/0x70 syzkaller/managers/android-5-10/kernel/arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 page last free stack trace: reset_page_owner syzkaller/managers/android-5-10/kernel/./include/linux/page_owner.h:28 [inline] free_pages_prepare syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:1331 [inline] free_pcp_prepare+0x18f/0x1c0 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:1405 free_unref_page_prepare syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:3291 [inline] free_unref_page_list+0x116/0x5d0 syzkaller/managers/android-5-10/kernel/mm/page_alloc.c:3361 release_pages+0xa62/0xaa0 syzkaller/managers/android-5-10/kernel/mm/swap.c:1081 free_pages_and_swap_cache+0x88/0xa0 syzkaller/managers/android-5-10/kernel/mm/swap_state.c:356 tlb_batch_pages_flush syzkaller/managers/android-5-10/kernel/mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free syzkaller/managers/android-5-10/kernel/mm/mmu_gather.c:242 [inline] tlb_flush_mmu+0x860/0xa00 syzkaller/managers/android-5-10/kernel/mm/mmu_gather.c:249 tlb_finish_mmu+0xd2/0x1f0 syzkaller/managers/android-5-10/kernel/mm/mmu_gather.c:328 exit_mmap+0x2e8/0x570 syzkaller/managers/android-5-10/kernel/mm/mmap.c:3326 __mmput+0x95/0x2c0 syzkaller/managers/android-5-10/kernel/kernel/fork.c:1128 mmput+0x4b/0x50 syzkaller/managers/android-5-10/kernel/kernel/fork.c:1149 exit_mm+0x615/0x7e0 syzkaller/managers/android-5-10/kernel/kernel/exit.c:489 do_exit+0x6c4/0x23a0 syzkaller/managers/android-5-10/kernel/kernel/exit.c:800 do_group_exit+0x16a/0x2d0 syzkaller/managers/android-5-10/kernel/kernel/exit.c:910 get_signal+0x133e/0x1f80 syzkaller/managers/android-5-10/kernel/kernel/signal.c:2790 arch_do_signal+0x8d/0x620 syzkaller/managers/android-5-10/kernel/arch/x86/kernel/signal.c:805 exit_to_user_mode_loop syzkaller/managers/android-5-10/kernel/kernel/entry/common.c:161 [inline] exit_to_user_mode_prepare+0xaa/0xe0 syzkaller/managers/android-5-10/kernel/kernel/entry/common.c:191 syscall_exit_to_user_mode+0x24/0x40 syzkaller/managers/android-5-10/kernel/kernel/entry/common.c:266 Memory state around the buggy address: ffff88814d603800: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc ffff88814d603880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff88814d603900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88814d603980: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88814d603a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 23973 at lib/refcount.c:28 refcount_warn_saturate+0x165/0x1b0 syzkaller/managers/android-5-10/kernel/lib/refcount.c:28 Modules linked in: CPU: 1 PID: 23973 Comm: io_wq_manager Tainted: G B 5.10.76-syzkaller-01178-g4944ec82ebb9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:refcount_warn_saturate+0x165/0x1b0 syzkaller/managers/android-5-10/kernel/lib/refcount.c:28 Code: c7 a0 ae 49 85 31 c0 e8 99 7b eb fe 0f 0b eb 83 e8 f0 98 18 ff c6 05 9e cc 68 04 01 48 c7 c7 00 af 49 85 31 c0 e8 7b 7b eb fe <0f> 0b e9 62 ff ff ff e8 cf 98 18 ff c6 05 7e cc 68 04 01 48 c7 c7 RSP: 0018:ffffc90002e47d20 EFLAGS: 00010246 RAX: 4ac3c8e097c6fb00 RBX: 0000000000000003 RCX: 1ffff920005c8f5c RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: ffffc90002e47d30 R08: ffffffff81545288 R09: ffffed103ee295d8 R10: ffffed103ee295d8 R11: 0000000000000000 R12: ffff88814d603918 R13: ffff88814d6038c0 R14: 0000000000000003 R15: ffff88814d60391c FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa16bc37a91 CR3: 000000010d52d000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __refcount_sub_and_test syzkaller/managers/android-5-10/kernel/./include/linux/refcount.h:283 [inline] refcount_sub_and_test syzkaller/managers/android-5-10/kernel/./include/linux/refcount.h:310 [inline] io_double_put_req syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2274 [inline] __io_req_task_cancel+0x1c3/0x720 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2070 io_req_task_cancel+0x51/0x130 syzkaller/managers/android-5-10/kernel/fs/io_uring.c:2078 task_work_run+0x147/0x1b0 syzkaller/managers/android-5-10/kernel/kernel/task_work.c:154 io_wq_manager+0x1aa/0x8b0 syzkaller/managers/android-5-10/kernel/fs/io-wq.c:797 kthread+0x371/0x390 syzkaller/managers/android-5-10/kernel/kernel/kthread.c:313 ret_from_fork+0x1f/0x30 syzkaller/managers/android-5-10/kernel/arch/x86/entry/entry_64.S:296 ---[ end trace 322f92d036d90383 ]---