KASAN: use-after-free Read in __fdget_raw

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 0347b1658399 Merge 5.10.93 into android12-5.10-lts
git tree: android12-5.10-lts
console output: https://syzkaller.appspot.com/x/log.txt?x=15c5013db00000
kernel config: https://syzkaller.appspot.com/x/.config?x=e0f3947457f8d2a4
dashboard link: https://syzkaller.appspot.com/bug?extid=569a9f38546d62a570d2
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13ab16d0700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15ac697bb00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+569a9f...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
BUG: KASAN: use-after-free in __fget_light fs/file.c:903 [inline]
BUG: KASAN: use-after-free in __fdget_raw+0x57/0x1e0 fs/file.c:923
Read of size 4 at addr ffff88811d4d0000 by task io_wqe_worker-0/374

CPU: 1 PID: 374 Comm: io_wqe_worker-0 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
check_region_inline mm/kasan/generic.c:135 [inline]
kasan_check_range+0x2b6/0x2f0 mm/kasan/generic.c:186
__kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31
instrument_atomic_read include/linux/instrumented.h:71 [inline]
atomic_read include/asm-generic/atomic-instrumented.h:27 [inline]
__fget_light fs/file.c:903 [inline]
__fdget_raw+0x57/0x1e0 fs/file.c:923
fdget_raw include/linux/file.h:70 [inline]
path_init+0x6aa/0x1130 fs/namei.c:2347
path_lookupat+0x2b/0x6c0 fs/namei.c:2403
filename_lookup+0x23f/0x6c0 fs/namei.c:2446
user_path_at_empty+0x40/0x50 fs/namei.c:2726
user_path_at include/linux/namei.h:59 [inline]
vfs_statx+0x10a/0x3f0 fs/stat.c:193
do_statx+0xec/0x170 fs/stat.c:588
io_statx fs/io_uring.c:4249 [inline]
io_issue_sqe+0x2541/0xfc10 fs/io_uring.c:6086
io_wq_submit_work+0x34c/0xf40 fs/io_uring.c:6155
io_worker_handle_work+0x1558/0x1d90 fs/io-wq.c:573
io_wqe_worker+0x39f/0xf20 fs/io-wq.c:615
kthread+0x371/0x390 kernel/kthread.c:313
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Allocated by task 365:
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]
slab_alloc_node mm/slub.c:2954 [inline]
slab_alloc mm/slub.c:2962 [inline]
kmem_cache_alloc+0x1a2/0x380 mm/slub.c:2967
dup_fd+0x71/0xc60 fs/file.c:293
copy_files kernel/fork.c:1517 [inline]
copy_process+0x12a6/0x5340 kernel/fork.c:2139
kernel_clone+0x21f/0x9a0 kernel/fork.c:2513
__do_sys_clone kernel/fork.c:2632 [inline]
__se_sys_clone kernel/fork.c:2616 [inline]
__x64_sys_clone+0x258/0x2d0 kernel/fork.c:2616
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 366:
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
put_files_struct+0x318/0x350 fs/file.c:434
exit_files+0x80/0xa0 fs/file.c:458
do_exit+0x6d9/0x23a0 kernel/exit.c:808
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
entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88811d4d0000
which belongs to the cache files_cache of size 704
The buggy address is located 0 bytes inside of
704-byte region [ffff88811d4d0000, ffff88811d4d02c0)
The buggy address belongs to the page:
page:ffffea0004753400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11d4d0
head:ffffea0004753400 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff888100066f00
raw: 0000000000000000 0000000080130013 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 357, ts 15953240908, free_ts 0
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
dup_fd+0x71/0xc60 fs/file.c:293
copy_files kernel/fork.c:1517 [inline]
copy_process+0x12a6/0x5340 kernel/fork.c:2139
kernel_clone+0x21f/0x9a0 kernel/fork.c:2513
__do_sys_clone kernel/fork.c:2632 [inline]
__se_sys_clone kernel/fork.c:2616 [inline]
__x64_sys_clone+0x258/0x2d0 kernel/fork.c:2616
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
page_owner free stack trace missing

Memory state around the buggy address:
ffff88811d4cff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88811d4cff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88811d4d0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88811d4d0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88811d4d0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
============================


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