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KASAN: use-after-free Read in io_kill_linked_timeout

Status: closed as invalid on 2022/03/05 18:28
Reported-by: syzbot+694deebd17dcc89c73f8@syzkaller.appspotmail.com
First crash: 1042d, last: 994d
Cause bisection: failed (error log, bisect log)
  

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in io_kill_linked_timeout+0x7fa/0x960 fs/io_uring.c:1932
Read of size 4 at addr ffff888117e842d8 by task io_wq_manager/12477

CPU: 0 PID: 12477 Comm: io_wq_manager Not tainted 5.10.93-syzkaller-01028-g0347b1658399 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x8d/0x3d0 mm/kasan/report.c:233
 __kasan_report+0x142/0x220 mm/kasan/report.c:419
 kasan_report+0x51/0x70 mm/kasan/report.c:436
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 io_kill_linked_timeout+0x7fa/0x960 fs/io_uring.c:1932
 __io_req_find_next fs/io_uring.c:2011 [inline]
 io_req_find_next fs/io_uring.c:2029 [inline]
 io_queue_next fs/io_uring.c:2128 [inline]
 io_free_req fs/io_uring.c:2136 [inline]
 io_put_req_deferred_cb+0xb2/0x520 fs/io_uring.c:2233
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 io_wq_manager+0x1aa/0x8b0 fs/io-wq.c:797
 kthread+0x371/0x390 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Allocated by task 12474:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:428 [inline]
 __kasan_slab_alloc+0xb2/0xe0 mm/kasan/common.c:461
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:583 [inline]
 kmem_cache_alloc_bulk+0x2d5/0x3f0 mm/slub.c:3412
 io_alloc_req fs/io_uring.c:1857 [inline]
 io_submit_sqes+0x6bf/0x2da0 fs/io_uring.c:6697
 __do_sys_io_uring_enter fs/io_uring.c:9113 [inline]
 __se_sys_io_uring_enter+0x322/0x12b0 fs/io_uring.c:9055
 __x64_sys_io_uring_enter+0xe5/0x100 fs/io_uring.c:9055
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 12477:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357
 ____kasan_slab_free+0x133/0x170 mm/kasan/common.c:360
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:368
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1602 [inline]
 slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1628
 slab_free mm/slub.c:3210 [inline]
 kmem_cache_free+0xb5/0x1f0 mm/slub.c:3226
 __io_free_req+0x20e/0x380 fs/io_uring.c:1912
 io_free_req fs/io_uring.c:2137 [inline]
 io_put_req_deferred_cb+0x64/0x520 fs/io_uring.c:2233
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 io_wq_manager+0x1aa/0x8b0 fs/io-wq.c:797
 kthread+0x371/0x390 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:345
 task_work_add+0xa7/0x320 kernel/task_work.c:39
 io_free_req_deferred fs/io_uring.c:2246 [inline]
 io_put_req_deferred+0x1c6/0x240 fs/io_uring.c:2254
 io_link_timeout_fn+0x4c8/0x600 fs/io_uring.c:6279
 __run_hrtimer+0x199/0x6a0 kernel/time/hrtimer.c:1583
 __hrtimer_run_queues kernel/time/hrtimer.c:1647 [inline]
 hrtimer_interrupt+0x639/0x1380 kernel/time/hrtimer.c:1709
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1084 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x3c0 arch/x86/kernel/apic/apic.c:1101
 asm_call_irq_on_stack+0xf/0x20
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0x85/0xe0 arch/x86/kernel/apic/apic.c:1095
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635

The buggy address belongs to the object at ffff888117e84280
 which belongs to the cache io_kiocb of size 216
The buggy address is located 88 bytes inside of
 216-byte region [ffff888117e84280, ffff888117e84358)
The buggy address belongs to the page:
page:ffffea00045fa100 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888117e84b40 pfn:0x117e84
flags: 0x8000000000000200(slab)
raw: 8000000000000200 ffffea0004323a00 0000000400000004 ffff8881041bc600
raw: ffff888117e84b40 00000000800c0009 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 1992, ts 36652228018, free_ts 36650470740
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2385 [inline]
 prep_new_page mm/page_alloc.c:2391 [inline]
 get_page_from_freelist+0xa74/0xa90 mm/page_alloc.c:4063
 __alloc_pages_nodemask+0x3c8/0x820 mm/page_alloc.c:5106
 alloc_slab_page mm/slub.c:1813 [inline]
 allocate_slab+0x6b/0x350 mm/slub.c:1815
 new_slab mm/slub.c:1876 [inline]
 new_slab_objects mm/slub.c:2635 [inline]
 ___slab_alloc+0x143/0x2f0 mm/slub.c:2798
 __slab_alloc mm/slub.c:2838 [inline]
 slab_alloc_node mm/slub.c:2920 [inline]
 slab_alloc mm/slub.c:2962 [inline]
 kmem_cache_alloc+0x26f/0x380 mm/slub.c:2967
 io_ring_ctx_alloc fs/io_uring.c:1186 [inline]
 io_uring_create+0x4ff/0x3490 fs/io_uring.c:9414
 io_uring_setup fs/io_uring.c:9557 [inline]
 __do_sys_io_uring_setup fs/io_uring.c:9563 [inline]
 __se_sys_io_uring_setup fs/io_uring.c:9560 [inline]
 __x64_sys_io_uring_setup+0x1ce/0x290 fs/io_uring.c:9560
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1331 [inline]
 free_pcp_prepare+0x18f/0x1c0 mm/page_alloc.c:1405
 free_unref_page_prepare mm/page_alloc.c:3291 [inline]
 free_unref_page_list+0x116/0x5d0 mm/page_alloc.c:3361
 release_pages+0xa62/0xaa0 mm/swap.c:1081
 free_pages_and_swap_cache+0x88/0xa0 mm/swap_state.c:356
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:242 [inline]
 tlb_flush_mmu+0x8c0/0xaa0 mm/mmu_gather.c:249
 tlb_finish_mmu+0xd2/0x1f0 mm/mmu_gather.c:328
 exit_mmap+0x319/0x5c0 mm/mmap.c:3328
 __mmput+0x95/0x2c0 kernel/fork.c:1133
 mmput+0x4b/0x50 kernel/fork.c:1154
 exit_mm+0x615/0x7e0 kernel/exit.c:489
 do_exit+0x6c4/0x23a0 kernel/exit.c:800
 do_group_exit+0x16a/0x2d0 kernel/exit.c:910
 __do_sys_exit_group+0x17/0x20 kernel/exit.c:921
 __se_sys_exit_group+0x14/0x20 kernel/exit.c:919
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:919
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46

Memory state around the buggy address:
 ffff888117e84180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888117e84200: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888117e84280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff888117e84300: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff888117e84380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 12477 at lib/refcount.c:28 refcount_warn_saturate+0x165/0x1b0 lib/refcount.c:28
Modules linked in:
CPU: 1 PID: 12477 Comm: io_wq_manager Tainted: G    B             5.10.93-syzkaller-01028-g0347b1658399 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0x165/0x1b0 lib/refcount.c:28
Code: c7 a0 bd 49 85 31 c0 e8 e9 34 eb fe 0f 0b eb 83 e8 c0 4e 18 ff c6 05 0e 95 68 04 01 48 c7 c7 00 be 49 85 31 c0 e8 cb 34 eb fe <0f> 0b e9 62 ff ff ff e8 9f 4e 18 ff c6 05 ee 94 68 04 01 48 c7 c7
RSP: 0018:ffffc90007f47cd0 EFLAGS: 00010246
RAX: c3d6f5e2e3f76500 RBX: 0000000000000003 RCX: 1ffff92000fe8f54
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffffc90007f47ce0 R08: ffffffff815457c8 R09: ffffed103ee2a5d8
R10: ffffed103ee2a5d8 R11: 0000000000000000 R12: ffff888117e842f0
R13: ffff88810a2d2918 R14: 0000000000000003 R15: 00000000ffffffff
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0ab366c1d0 CR3: 0000000117519000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __refcount_sub_and_test include/linux/refcount.h:283 [inline]
 __refcount_dec_and_test include/linux/refcount.h:315 [inline]
 refcount_dec_and_test include/linux/refcount.h:333 [inline]
 io_put_req fs/io_uring.c:2225 [inline]
 io_kill_linked_timeout+0x3f4/0x960 fs/io_uring.c:1949
 __io_req_find_next fs/io_uring.c:2011 [inline]
 io_req_find_next fs/io_uring.c:2029 [inline]
 io_queue_next fs/io_uring.c:2128 [inline]
 io_free_req fs/io_uring.c:2136 [inline]
 io_put_req_deferred_cb+0xb2/0x520 fs/io_uring.c:2233
 task_work_run+0x147/0x1b0 kernel/task_work.c:154
 io_wq_manager+0x1aa/0x8b0 fs/io-wq.c:797
 kthread+0x371/0x390 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
---[ end trace 8879259892d57858 ]---

Crashes (14):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/01/23 15:40 android12-5.10-lts 0347b1658399 214351e1 .config console log report syz C ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/03/05 16:05 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/03/05 12:34 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/03/02 15:13 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/27 01:29 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/26 20:58 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/25 19:28 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/25 18:43 android12-5.10-lts e1b86e7f5cbb 45a13a73 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/25 18:00 android12-5.10-lts e1b86e7f5cbb 7c337266 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/25 17:13 android12-5.10-lts e1b86e7f5cbb 7c337266 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/25 13:44 android12-5.10-lts cbfab5c59cf6 7c337266 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/02/12 13:59 android12-5.10-lts 86e6176a4240 8b9ca619 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/01/23 15:27 android12-5.10-lts 0347b1658399 214351e1 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
2022/01/16 16:58 android12-5.10-lts d605f2f30d54 723cfaf0 .config console log report info ci2-android-5-10 KASAN: use-after-free Read in io_kill_linked_timeout
* Struck through repros no longer work on HEAD.