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KASAN: use-after-free Write in io_queue_worker_create

Status: fixed on 2022/03/08 16:11
Subsystems: fs io-uring
[Documentation on labels]
Reported-by: syzbot+b60c982cb0efc5e05a47@syzkaller.appspotmail.com
Fix commit: 71a85387546e io-wq: check for wq exit after adding new worker task_work e47498afeca9 io-wq: remove spurious bit clear on task_work addition
First crash: 872d, last: 861d
Cause bisection: introduced by (bisect log) [no-op commit]:
commit 360d1b65449356f56287e49d1b3d7579e758ca29
Author: Ian Chen <ian.chen@amd.com>
Date: Thu Jun 24 02:48:43 2021 +0000

  drm/amd/display: Extend dmub_cmd_psr_copy_settings_data struct

Crash: BUG: sleeping function called from invalid context in lock_sock_nested (log)
Repro: C syz .config
  
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[PATCH 5.15 000/177] 5.15.11-rc1 review 183 (183) 2021/12/21 23:14
[PATCH] io-wq: check for wq exit after adding new worker task_work 2 (2) 2021/12/10 18:38
[syzbot] KASAN: use-after-free Write in io_queue_worker_create 3 (7) 2021/12/10 16:15
▶ ▼ Last patch testing requests (2)
Created Duration User Patch Repo Result
2021/12/10 15:33 18m axboe@kernel.dk git://git.kernel.dk/linux-block io_uring-5.16 OK
2021/12/10 05:26 17m axboe@kernel.dk git://git.kernel.dk/linux-block io_uring-5.16 report log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_write include/linux/instrumented.h:86 [inline]
BUG: KASAN: use-after-free in io_queue_worker_create+0x1cc/0x320 include/asm-generic/bitops/instrumented-lock.h:25
Write of size 8 at addr ffff88807b52f0d8 by task kworker/0:3/3267

CPU: 0 PID: 3267 Comm: kworker/0:3 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events io_workqueue_create
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
 print_address_description+0x65/0x380 mm/kasan/report.c:247
 __kasan_report mm/kasan/report.c:433 [inline]
 kasan_report+0x19a/0x1f0 mm/kasan/report.c:450
 kasan_check_range+0x2b5/0x2f0 mm/kasan/generic.c:189
 instrument_atomic_write include/linux/instrumented.h:86 [inline]
 io_queue_worker_create+0x1cc/0x320 include/asm-generic/bitops/instrumented-lock.h:25
 io_workqueue_create+0x75/0xb0 fs/io-wq.c:780
 process_one_work+0x853/0x1140 kernel/workqueue.c:2298
 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445
 kthread+0x468/0x490 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30
 </TASK>

Allocated by task 3621:
 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:434 [inline]
 ____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:269 [inline]
 kmem_cache_alloc_node_trace+0x26f/0x370 mm/slub.c:3289
 kmalloc_node include/linux/slab.h:608 [inline]
 kzalloc_node include/linux/slab.h:735 [inline]
 create_io_worker+0xef/0x630 fs/io-wq.c:792
 create_worker_cb+0x16e/0x340 fs/io-wq.c:329
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 tracehook_notify_signal include/linux/tracehook.h:214 [inline]
 handle_signal_work kernel/entry/common.c:146 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x180/0x220 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 3621:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x10d/0x150 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1749
 slab_free mm/slub.c:3513 [inline]
 kfree+0xe1/0x330 mm/slub.c:4561
 create_worker_cont+0x4ca/0x5a0 fs/io-wq.c:766
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 tracehook_notify_signal include/linux/tracehook.h:214 [inline]
 handle_signal_work kernel/entry/common.c:146 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x180/0x220 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xfa/0x130 mm/kasan/generic.c:348
 task_work_add+0x2f/0x1b0 kernel/task_work.c:38
 io_queue_worker_create+0x1b4/0x320 fs/io-wq.c:362
 io_workqueue_create+0x75/0xb0 fs/io-wq.c:780
 process_one_work+0x853/0x1140 kernel/workqueue.c:2298
 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445
 kthread+0x468/0x490 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xfa/0x130 mm/kasan/generic.c:348
 insert_work+0x54/0x400 kernel/workqueue.c:1354
 __queue_work+0x928/0xc60 kernel/workqueue.c:1520
 queue_work_on+0x12b/0x220 kernel/workqueue.c:1547
 queue_work include/linux/workqueue.h:502 [inline]
 schedule_work include/linux/workqueue.h:563 [inline]
 create_worker_cont+0x442/0x5a0 fs/io-wq.c:772
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 tracehook_notify_signal include/linux/tracehook.h:214 [inline]
 handle_signal_work kernel/entry/common.c:146 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x180/0x220 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff88807b52f000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 216 bytes inside of
 512-byte region [ffff88807b52f000, ffff88807b52f200)
The buggy address belongs to the page:
page:ffffea0001ed4b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7b52c
head:ffffea0001ed4b00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011441c80
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 3621, ts 51184877647, free_ts 17901522119
 prep_new_page mm/page_alloc.c:2418 [inline]
 get_page_from_freelist+0x729/0x9e0 mm/page_alloc.c:4149
 __alloc_pages+0x255/0x580 mm/page_alloc.c:5369
 __alloc_pages_node include/linux/gfp.h:570 [inline]
 alloc_slab_page mm/slub.c:1795 [inline]
 allocate_slab+0x89/0x4d0 mm/slub.c:1930
 new_slab mm/slub.c:1993 [inline]
 ___slab_alloc+0x41e/0xc40 mm/slub.c:3022
 __slab_alloc mm/slub.c:3109 [inline]
 slab_alloc_node mm/slub.c:3200 [inline]
 kmem_cache_alloc_node_trace+0x2ca/0x370 mm/slub.c:3284
 kmalloc_node include/linux/slab.h:608 [inline]
 kzalloc_node include/linux/slab.h:735 [inline]
 create_io_worker+0xef/0x630 fs/io-wq.c:792
 create_worker_cb+0x16e/0x340 fs/io-wq.c:329
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 tracehook_notify_signal include/linux/tracehook.h:214 [inline]
 handle_signal_work kernel/entry/common.c:146 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x180/0x220 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0xd1c/0xe00 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3309 [inline]
 free_unref_page+0x7d/0x580 mm/page_alloc.c:3388
 free_slab mm/slub.c:2033 [inline]
 discard_slab mm/slub.c:2039 [inline]
 __unfreeze_partials+0x1ab/0x200 mm/slub.c:2527
 put_cpu_partial+0x116/0x180 mm/slub.c:2603
 do_slab_free mm/slub.c:3501 [inline]
 ___cache_free+0xe6/0x120 mm/slub.c:3520
 qlist_free_all mm/kasan/quarantine.c:165 [inline]
 kasan_quarantine_reduce+0x151/0x1c0 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3234 [inline]
 slab_alloc mm/slub.c:3242 [inline]
 __kmalloc+0x1ed/0x380 mm/slub.c:4419
 kmalloc include/linux/slab.h:595 [inline]
 tomoyo_realpath_from_path+0xd8/0x610 security/tomoyo/realpath.c:254
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x238/0x660 security/tomoyo/file.c:822
 security_inode_getattr+0xc0/0x140 security/security.c:1334
 vfs_getattr fs/stat.c:157 [inline]
 vfs_statx+0x168/0x3f0 fs/stat.c:225
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:412 [inline]
 __se_sys_newfstatat+0xc8/0x760 fs/stat.c:406
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff88807b52ef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807b52f000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807b52f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88807b52f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807b52f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (132):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/10 10:14 upstream c741e49150db 4d4ce9bc .config console log report syz C ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 05:20 upstream c741e49150db 4d4ce9bc .config console log report syz C ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/12 05:48 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/12 03:21 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/12 00:02 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 19:50 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 14:07 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 12:50 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 11:30 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 08:27 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 06:34 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 04:23 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 00:04 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 22:44 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 20:58 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 19:35 upstream c741e49150db 49ca1f59 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 17:51 upstream c741e49150db 49ca1f59 .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 16:35 upstream c741e49150db 49ca1f59 .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 15:45 upstream c741e49150db 49ca1f59 .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 14:34 upstream c741e49150db fc17c959 .config console log report info ci-qemu-upstream KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 07:57 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 06:24 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 04:47 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 03:44 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 03:39 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 02:35 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 02:31 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 01:59 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 01:32 upstream ded746bfc943 4d4ce9bc .config console log report info ci-qemu-upstream KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 00:54 upstream c741e49150db b54aa474 .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 00:53 upstream c741e49150db b54aa474 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 00:30 upstream c741e49150db b54aa474 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 00:15 upstream c741e49150db b54aa474 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 00:05 upstream c741e49150db b54aa474 .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 00:02 upstream c741e49150db b54aa474 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/06 02:58 upstream 944207047ca4 a617004c .config console log report info ci-qemu-upstream KASAN: use-after-free Write in io_queue_worker_create
2021/12/04 18:41 upstream bbef3c7a63d2 a617004c .config console log report info ci-qemu-upstream KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 17:32 upstream 6f513529296f 49ca1f59 .config console log report info ci-qemu-upstream-386 KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 16:28 upstream 6f513529296f 49ca1f59 .config console log report info ci-upstream-kasan-gce-386 KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 09:27 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce-386 KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 21:37 upstream b8a98b6bf66a 49ca1f59 .config console log report info ci-upstream-kasan-gce-386 KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 03:31 upstream c741e49150db 4d4ce9bc .config console log report info ci-upstream-kasan-gce-386 KASAN: use-after-free Write in io_queue_worker_create
2021/12/10 01:16 upstream ded746bfc943 4d4ce9bc .config console log report info ci-qemu-upstream-386 KASAN: use-after-free Write in io_queue_worker_create
2021/12/15 18:09 linux-next ea922272cbe5 572bcb40 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/15 05:21 linux-next ea922272cbe5 f752fb53 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/14 21:50 linux-next ea922272cbe5 d018dd31 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/14 10:04 linux-next ea922272cbe5 5d14b1ea .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/13 22:02 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/13 18:23 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/13 14:42 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/13 12:42 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/13 00:40 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/12 09:27 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/11 05:29 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Write in io_queue_worker_create
2021/12/12 16:10 linux-next ea922272cbe5 49ca1f59 .config console log report info ci-upstream-linux-next-kasan-gce-root KFENCE: use-after-free in io_queue_worker_create
* Struck through repros no longer work on HEAD.