[syzbot ci] Re: block: fix aligning of bounced dio read bios

[syzbot ci <syzbot+cid84789865f9e9652@syzkaller.appspotmail.com>]

syzbot ci has tested the following series

[v1] block: fix aligning of bounced dio read bios
https://lore.kernel.org/all/20260713152912.2333321-1-hch@lst.de
* [PATCH] block: fix aligning of bounced dio read bios

and found the following issues:
* KASAN: slab-out-of-bounds Read in bio_iov_iter_get_pages
* KASAN: stack-out-of-bounds Read in bio_iov_iter_get_pages
* KASAN: use-after-free Read in bio_iov_iter_get_pages

Full report is available here:
https://ci.syzbot.org/series/c5526ca4-0280-46b9-acac-a3952d0df609

***

KASAN: slab-out-of-bounds Read in bio_iov_iter_get_pages

tree:      torvalds
URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
base:      a13c140cc289c0b7b3770bce5b3ad42ab35074aa
arch:      amd64
compiler:  Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6
config:    https://ci.syzbot.org/builds/826b3d15-d916-4201-92f4-a3110bf41809/config
syz repro: https://ci.syzbot.org/findings/329bf95d-8223-48af-b49b-aad0ba31512c/syz_repro

==================================================================
BUG: KASAN: slab-out-of-bounds in bio_iov_iter_align_down block/bio.c:1204 [inline]
BUG: KASAN: slab-out-of-bounds in bio_iov_iter_get_pages+0x818/0xb00 block/bio.c:1278
Read of size 4 at addr ffff8881774e32f8 by task syz.2.19/5857

CPU: 1 UID: 0 PID: 5857 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 bio_iov_iter_align_down block/bio.c:1204 [inline]
 bio_iov_iter_get_pages+0x818/0xb00 block/bio.c:1278
 blkdev_iov_iter_get_pages block/fops.c:49 [inline]
 __blkdev_direct_IO+0x656/0xf30 block/fops.c:219
 blkdev_direct_IO+0x122e/0x17a0 block/fops.c:435
 blkdev_read_iter+0x223/0x420 block/fops.c:814
 do_iter_readv_writev+0x612/0x8c0 fs/read_write.c:-1
 vfs_readv+0x28d/0x850 fs/read_write.c:1019
 do_preadv fs/read_write.c:1133 [inline]
 __do_sys_preadv2 fs/read_write.c:1192 [inline]
 __se_sys_preadv2+0x177/0x2a0 fs/read_write.c:1183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff72e39ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff72f2bf028 EFLAGS: 00000246 ORIG_RAX: 0000000000000147
RAX: ffffffffffffffda RBX: 00007ff72e615fa0 RCX: 00007ff72e39ce59
RDX: 0000000000000002 RSI: 0000200000000400 RDI: 0000000000000003
RBP: 00007ff72e432e6f R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff72e616038 R14: 00007ff72e615fa0 R15: 00007fff57584868
 </TASK>

Allocated by task 1:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4612 [inline]
 slab_alloc_node mm/slub.c:4945 [inline]
 kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4959
 mempool_init_node+0x1f4/0x4f0 mm/mempool.c:259
 mempool_init_noprof+0x3a/0x50 mm/mempool.c:289
 biovec_init_pool block/bio.c:1909 [inline]
 bioset_init+0x5c1/0x7e0 block/bio.c:1978
 btrfs_init_dio+0x1f/0x30 fs/btrfs/direct-io.c:1145
 init_btrfs_fs+0x6d/0x1f0 fs/btrfs/super.c:2727
 do_one_initcall+0x250/0x870 init/main.c:1347
 do_initcall_level+0x10a/0x1a0 init/main.c:1409
 do_initcalls+0x59/0xa0 init/main.c:1425
 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658
 kernel_init+0x1d/0x1d0 init/main.c:1548
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 1:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_mempool_poison_object+0x16e/0x1d0 mm/kasan/common.c:539
 kasan_mempool_poison_object include/linux/kasan.h:363 [inline]
 kasan_poison_element mm/mempool.c:156 [inline]
 add_element mm/mempool.c:179 [inline]
 mempool_init_node+0x2a6/0x4f0 mm/mempool.c:264
 mempool_init_noprof+0x3a/0x50 mm/mempool.c:289
 biovec_init_pool block/bio.c:1909 [inline]
 bioset_init+0x5c1/0x7e0 block/bio.c:1978
 btrfs_init_dio+0x1f/0x30 fs/btrfs/direct-io.c:1145
 init_btrfs_fs+0x6d/0x1f0 fs/btrfs/super.c:2727
 do_one_initcall+0x250/0x870 init/main.c:1347
 do_initcall_level+0x10a/0x1a0 init/main.c:1409
 do_initcalls+0x59/0xa0 init/main.c:1425
 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658
 kernel_init+0x1d/0x1d0 init/main.c:1548
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff8881774e2200
 which belongs to the cache biovec-max of size 4096
The buggy address is located 248 bytes to the right of
 allocated 4096-byte region [ffff8881774e2200, ffff8881774e3200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1774e0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff888160414b40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800070007 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff888160414b40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800070007 00000000f5000000 0000000000000000
head: 057ff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 22595717829, free_ts 19809479246
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3294 [inline]
 allocate_slab+0x79/0x5e0 mm/slub.c:3408
 new_slab mm/slub.c:3454 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7338
 refill_sheaf mm/slub.c:2832 [inline]
 __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4703
 alloc_from_pcs mm/slub.c:4801 [inline]
 slab_alloc_node mm/slub.c:4933 [inline]
 kmem_cache_alloc_noprof+0x382/0x5f0 mm/slub.c:4959
 mempool_init_node+0x1f4/0x4f0 mm/mempool.c:259
 mempool_init_noprof+0x3a/0x50 mm/mempool.c:289
 biovec_init_pool block/bio.c:1909 [inline]
 bioset_init+0x5c1/0x7e0 block/bio.c:1978
 btrfs_init_dio+0x1f/0x30 fs/btrfs/direct-io.c:1145
 init_btrfs_fs+0x6d/0x1f0 fs/btrfs/super.c:2727
 do_one_initcall+0x250/0x870 init/main.c:1347
 do_initcall_level+0x10a/0x1a0 init/main.c:1409
 do_initcalls+0x59/0xa0 init/main.c:1425
 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658
page last free pid 11 tgid 11 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 free_pages_prepare+0x960/0xa60 mm/page_alloc.c:1451
 __free_contig_range_common+0x174/0x340 mm/page_alloc.c:6897
 __free_contig_range mm/page_alloc.c:6942 [inline]
 free_pages_bulk+0x48/0x120 mm/page_alloc.c:5257
 vm_area_free_pages mm/vmalloc.c:3439 [inline]
 vfree+0x224/0x4a0 mm/vmalloc.c:3488
 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:3392
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff8881774e3180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881774e3200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881774e3280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff8881774e3300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881774e3380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================


***

KASAN: stack-out-of-bounds Read in bio_iov_iter_get_pages

tree:      torvalds
URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
base:      a13c140cc289c0b7b3770bce5b3ad42ab35074aa
arch:      amd64
compiler:  Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6
config:    https://ci.syzbot.org/builds/826b3d15-d916-4201-92f4-a3110bf41809/config
syz repro: https://ci.syzbot.org/findings/7548167b-8086-40cf-b7c4-0729bb64a887/syz_repro

==================================================================
BUG: KASAN: stack-out-of-bounds in bio_iov_iter_align_down block/bio.c:1204 [inline]
BUG: KASAN: stack-out-of-bounds in bio_iov_iter_get_pages+0x818/0xb00 block/bio.c:1278
Read of size 4 at addr ffffc90003d0f8d8 by task syz.0.17/5816

CPU: 1 UID: 0 PID: 5816 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 bio_iov_iter_align_down block/bio.c:1204 [inline]
 bio_iov_iter_get_pages+0x818/0xb00 block/bio.c:1278
 blkdev_iov_iter_get_pages block/fops.c:49 [inline]
 __blkdev_direct_IO_simple block/fops.c:87 [inline]
 blkdev_direct_IO+0x103c/0x17a0 block/fops.c:429
 blkdev_direct_write+0x7c/0x140 block/fops.c:697
 blkdev_write_iter+0x52d/0x700 block/fops.c:765
 do_iter_readv_writev+0x612/0x8c0 fs/read_write.c:-1
 vfs_writev+0x343/0x990 fs/read_write.c:1058
 do_pwritev fs/read_write.c:1154 [inline]
 __do_sys_pwritev2 fs/read_write.c:1212 [inline]
 __se_sys_pwritev2+0x177/0x2a0 fs/read_write.c:1203
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f69e2f9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f69e3dd7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f69e3215fa0 RCX: 00007f69e2f9ce59
RDX: 0000000000000001 RSI: 00002000000004c0 RDI: 0000000000000003
RBP: 00007f69e3032e6f R08: 0000000000000006 R09: 000000000000000a
R10: 0000000000000400 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f69e3216038 R14: 00007f69e3215fa0 R15: 00007ffd3e932d38
 </TASK>

The buggy address belongs to stack of task syz.0.17/5816
 and is located at offset 24 in frame:
 blkdev_direct_IO+0x0/0x17a0 block/fops.c:467

This frame has 2 objects:
 [32, 96) 'inline_vecs.i'
 [128, 264) 'bio.i'

The buggy address belongs to a vmalloc virtual mapping
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1bc8af
memcg:ffff888171c78902
flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
raw: 057ff00000000000 0000000000000000 ffffea0006f22b88 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888171c78902
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x29c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO), pid 5815, tgid 5815 (syz.0.17), ts 75932045692, free_ts 28228426703
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_pages_mpol+0x212/0x380 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0xac/0x2a0 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3667 [inline]
 __vmalloc_area_node mm/vmalloc.c:3892 [inline]
 __vmalloc_node_range_noprof+0x795/0x1730 mm/vmalloc.c:4082
 __vmalloc_node_noprof+0xc2/0x100 mm/vmalloc.c:4143
 alloc_thread_stack_node kernel/fork.c:359 [inline]
 dup_task_struct+0x2a0/0x8e0 kernel/fork.c:929
 copy_process+0x820/0x4390 kernel/fork.c:2115
 kernel_clone+0x2d7/0x940 kernel/fork.c:2748
 __do_sys_clone3 kernel/fork.c:3050 [inline]
 __se_sys_clone3+0x33c/0x360 kernel/fork.c:3029
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5066 tgid 5066 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950
 __slab_free+0x274/0x2c0 mm/slub.c:5767
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4612 [inline]
 slab_alloc_node mm/slub.c:4945 [inline]
 kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4959
 alloc_filename fs/namei.c:147 [inline]
 do_getname+0x2e/0x250 fs/namei.c:187
 getname_flags fs/namei.c:230 [inline]
 getname include/linux/fs.h:2537 [inline]
 class_filename_constructor include/linux/fs.h:2564 [inline]
 __do_sys_symlink fs/namei.c:5710 [inline]
 __se_sys_symlink+0x2b/0x2b0 fs/namei.c:5708
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffffc90003d0f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90003d0f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90003d0f880: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
                                                    ^
 ffffc90003d0f900: 00 00 00 00 f2 f2 f2 f2 00 00 00 00 00 00 00 00
 ffffc90003d0f980: 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3
==================================================================


***

KASAN: use-after-free Read in bio_iov_iter_get_pages

tree:      torvalds
URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux
base:      a13c140cc289c0b7b3770bce5b3ad42ab35074aa
arch:      amd64
compiler:  Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6
config:    https://ci.syzbot.org/builds/826b3d15-d916-4201-92f4-a3110bf41809/config
syz repro: https://ci.syzbot.org/findings/9daf86a2-4bc7-464d-9b7d-713887f8d527/syz_repro

==================================================================
BUG: KASAN: use-after-free in bio_iov_iter_align_down block/bio.c:1204 [inline]
BUG: KASAN: use-after-free in bio_iov_iter_get_pages+0x818/0xb00 block/bio.c:1278
Read of size 4 at addr ffff88816bf6fff8 by task syz.2.19/5822

CPU: 1 UID: 0 PID: 5822 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 bio_iov_iter_align_down block/bio.c:1204 [inline]
 bio_iov_iter_get_pages+0x818/0xb00 block/bio.c:1278
 blkdev_iov_iter_get_pages block/fops.c:49 [inline]
 __blkdev_direct_IO+0x656/0xf30 block/fops.c:219
 blkdev_direct_IO+0x122e/0x17a0 block/fops.c:435
 blkdev_read_iter+0x223/0x420 block/fops.c:814
 do_iter_readv_writev+0x612/0x8c0 fs/read_write.c:-1
 vfs_readv+0x28d/0x850 fs/read_write.c:1019
 do_preadv fs/read_write.c:1133 [inline]
 __do_sys_preadv2 fs/read_write.c:1192 [inline]
 __se_sys_preadv2+0x177/0x2a0 fs/read_write.c:1183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc69259ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc691bfe028 EFLAGS: 00000246 ORIG_RAX: 0000000000000147
RAX: ffffffffffffffda RBX: 00007fc692815fa0 RCX: 00007fc69259ce59
RDX: 0000000000000006 RSI: 0000200000000e80 RDI: 0000000000000003
RBP: 00007fc692632e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc692816038 R14: 00007fc692815fa0 R15: 00007ffe0610dd38
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16bf6f
flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
raw: 057ff00000000000 0000000000000000 ffffea0005afdbc8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5461, tgid 5461 (rm), ts 41922484692, free_ts 75795985916
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3294 [inline]
 allocate_slab+0x79/0x5e0 mm/slub.c:3408
 new_slab mm/slub.c:3454 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7338
 refill_sheaf mm/slub.c:2832 [inline]
 __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4703
 alloc_from_pcs mm/slub.c:4801 [inline]
 slab_alloc_node mm/slub.c:4933 [inline]
 __do_kmalloc_node mm/slub.c:5361 [inline]
 __kmalloc_noprof+0x485/0x720 mm/slub.c:5387
 _kmalloc_noprof include/linux/slab.h:973 [inline]
 tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827
 security_inode_getattr+0x12b/0x310 security/security.c:1895
 vfs_getattr fs/stat.c:259 [inline]
 vfs_fstat fs/stat.c:281 [inline]
 vfs_fstatat+0xb4/0x170 fs/stat.c:371
 __do_sys_newfstatat fs/stat.c:538 [inline]
 __se_sys_newfstatat fs/stat.c:532 [inline]
 __x64_sys_newfstatat+0x151/0x200 fs/stat.c:532
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5753 tgid 5753 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950
 __slab_free+0x274/0x2c0 mm/slub.c:5767
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4612 [inline]
 slab_alloc_node mm/slub.c:4945 [inline]
 __do_kmalloc_node mm/slub.c:5361 [inline]
 __kvmalloc_node_noprof+0x4cd/0x860 mm/slub.c:6933
 proc_sys_call_handler+0x3d0/0x830 fs/proc/proc_sysctl.c:583
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:687
 ksys_write+0x150/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88816bf6fe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88816bf6ff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88816bf6ff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff88816bf70000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88816bf70080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================


***

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