==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebce000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Not tainted 6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14385:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4347
 __do_krealloc mm/slub.c:4905 [inline]
 krealloc_noprof+0x156/0x370 mm/slub.c:4958
 bch2_sb_realloc+0x20f/0x590 fs/bcachefs/super-io.c:222
 read_one_super+0x2e0/0x1580 fs/bcachefs/super-io.c:759
 __bch2_read_super+0x4d5/0x1120 fs/bcachefs/super-io.c:851
 bch2_fs_open+0x313/0xc50 fs/bcachefs/super.c:2391
 bch2_fs_get_tree+0xcbe/0x1b20 fs/bcachefs/fs.c:2473
 vfs_get_tree+0x8e/0x340 fs/super.c:1804
 do_new_mount fs/namespace.c:3885 [inline]
 path_mount+0x1414/0x2020 fs/namespace.c:4209
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount fs/namespace.c:4410 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebcc000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 0 bytes to the right of
 allocated 8192-byte region [ffff88807ebcc000, ffff88807ebce000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebc8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf201 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5569, tgid 5569 (S50crond), ts 71094773892, free_ts 69716881713
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
 tomoyo_init_log+0xc8a/0x2140 security/tomoyo/audit.c:264
 tomoyo_supervisor+0x302/0x13b0 security/tomoyo/common.c:2198
 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
 tomoyo_env_perm+0x191/0x200 security/tomoyo/environ.c:63
 tomoyo_environ security/tomoyo/domain.c:672 [inline]
 tomoyo_find_next_domain+0xec2/0x20b0 security/tomoyo/domain.c:888
 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline]
 tomoyo_bprm_check_security+0x12e/0x1d0 security/tomoyo/tomoyo.c:92
 security_bprm_check+0x1b9/0x1e0 security/security.c:1302
 search_binary_handler fs/exec.c:1655 [inline]
 exec_binprm fs/exec.c:1697 [inline]
 bprm_execve fs/exec.c:1749 [inline]
 bprm_execve+0x810/0x1650 fs/exec.c:1725
 do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1855
page last free pid 5537 tgid 5537 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88807ebcdf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807ebcdf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807ebce000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807ebce080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebce100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebcf000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14385:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4347
 __do_krealloc mm/slub.c:4905 [inline]
 krealloc_noprof+0x156/0x370 mm/slub.c:4958
 bch2_sb_realloc+0x20f/0x590 fs/bcachefs/super-io.c:222
 read_one_super+0x2e0/0x1580 fs/bcachefs/super-io.c:759
 __bch2_read_super+0x4d5/0x1120 fs/bcachefs/super-io.c:851
 bch2_fs_open+0x313/0xc50 fs/bcachefs/super.c:2391
 bch2_fs_get_tree+0xcbe/0x1b20 fs/bcachefs/fs.c:2473
 vfs_get_tree+0x8e/0x340 fs/super.c:1804
 do_new_mount fs/namespace.c:3885 [inline]
 path_mount+0x1414/0x2020 fs/namespace.c:4209
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount fs/namespace.c:4410 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebcc000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 4096 bytes to the right of
 allocated 8192-byte region [ffff88807ebcc000, ffff88807ebce000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebc8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf201 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5569, tgid 5569 (S50crond), ts 71094773892, free_ts 69716881713
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
 tomoyo_init_log+0xc8a/0x2140 security/tomoyo/audit.c:264
 tomoyo_supervisor+0x302/0x13b0 security/tomoyo/common.c:2198
 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
 tomoyo_env_perm+0x191/0x200 security/tomoyo/environ.c:63
 tomoyo_environ security/tomoyo/domain.c:672 [inline]
 tomoyo_find_next_domain+0xec2/0x20b0 security/tomoyo/domain.c:888
 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline]
 tomoyo_bprm_check_security+0x12e/0x1d0 security/tomoyo/tomoyo.c:92
 security_bprm_check+0x1b9/0x1e0 security/security.c:1302
 search_binary_handler fs/exec.c:1655 [inline]
 exec_binprm fs/exec.c:1697 [inline]
 bprm_execve fs/exec.c:1749 [inline]
 bprm_execve+0x810/0x1650 fs/exec.c:1725
 do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1855
page last free pid 5537 tgid 5537 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88807ebcef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebcef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807ebcf000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807ebcf080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebcf100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-use-after-free in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-use-after-free in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-use-after-free in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebd0000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 vfs_fstatat+0x85/0xf0 fs/stat.c:376
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebd0000
 which belongs to the cache names_cache of size 4096
The buggy address is located 0 bytes inside of
 freed 4096-byte region [ffff88807ebd0000, ffff88807ebd1000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf401 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 5199, tgid 5199 (udevd), ts 360509543199, free_ts 360182122805
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5843 tgid 5843 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195
 __vmf_anon_prepare+0x11c/0x240 mm/memory.c:3523
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_anonymous_page mm/memory.c:5087 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault+0x27f6/0x5490 mm/memory.c:6232
 handle_mm_fault+0x589/0xd10 mm/memory.c:6401
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff88807ebcff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebcff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807ebd0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88807ebd0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebd1000 by task kworker/u8:10/6464

CPU: 1 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 vfs_fstatat+0x85/0xf0 fs/stat.c:376
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebd0000
 which belongs to the cache names_cache of size 4096
The buggy address is located 0 bytes to the right of
 allocated 4096-byte region [ffff88807ebd0000, ffff88807ebd1000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf401 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 5199, tgid 5199 (udevd), ts 360509543199, free_ts 360182122805
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5843 tgid 5843 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195
 __vmf_anon_prepare+0x11c/0x240 mm/memory.c:3523
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_anonymous_page mm/memory.c:5087 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault+0x27f6/0x5490 mm/memory.c:6232
 handle_mm_fault+0x589/0xd10 mm/memory.c:6401
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff88807ebd0f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd0f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807ebd1000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807ebd1080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebd1100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-use-after-free in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-use-after-free in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-use-after-free in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebd2000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 do_sys_openat2+0xb8/0x1d0 fs/open.c:1431
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 do_sys_openat2+0x152/0x1d0 fs/open.c:1445
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebd1100
 which belongs to the cache names_cache of size 4096
The buggy address is located 3840 bytes inside of
 freed 4096-byte region [ffff88807ebd1100, ffff88807ebd2100)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf401 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 5199, tgid 5199 (udevd), ts 360509543199, free_ts 360182122805
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5843 tgid 5843 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195
 __vmf_anon_prepare+0x11c/0x240 mm/memory.c:3523
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_anonymous_page mm/memory.c:5087 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault+0x27f6/0x5490 mm/memory.c:6232
 handle_mm_fault+0x589/0xd10 mm/memory.c:6401
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff88807ebd1f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd1f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807ebd2000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88807ebd2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-use-after-free in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-use-after-free in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-use-after-free in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebd3000 by task kworker/u8:10/6464

CPU: 1 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14358:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 do_sys_openat2+0xb8/0x1d0 fs/open.c:1431
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14358:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 do_sys_openat2+0x152/0x1d0 fs/open.c:1445
 do_sys_open fs/open.c:1452 [inline]
 __do_sys_openat fs/open.c:1468 [inline]
 __se_sys_openat fs/open.c:1463 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1463
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebd2200
 which belongs to the cache names_cache of size 4096
The buggy address is located 3584 bytes inside of
 freed 4096-byte region [ffff88807ebd2200, ffff88807ebd3200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf401 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 5199, tgid 5199 (udevd), ts 360509543199, free_ts 360182122805
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5843 tgid 5843 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195
 __vmf_anon_prepare+0x11c/0x240 mm/memory.c:3523
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_anonymous_page mm/memory.c:5087 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault+0x27f6/0x5490 mm/memory.c:6232
 handle_mm_fault+0x589/0xd10 mm/memory.c:6401
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff88807ebd2f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd2f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807ebd3000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88807ebd3080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd3100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebce000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14385:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4347
 __do_krealloc mm/slub.c:4905 [inline]
 krealloc_noprof+0x156/0x370 mm/slub.c:4958
 bch2_sb_realloc+0x20f/0x590 fs/bcachefs/super-io.c:222
 read_one_super+0x2e0/0x1580 fs/bcachefs/super-io.c:759
 __bch2_read_super+0x4d5/0x1120 fs/bcachefs/super-io.c:851
 bch2_fs_open+0x313/0xc50 fs/bcachefs/super.c:2391
 bch2_fs_get_tree+0xcbe/0x1b20 fs/bcachefs/fs.c:2473
 vfs_get_tree+0x8e/0x340 fs/super.c:1804
 do_new_mount fs/namespace.c:3885 [inline]
 path_mount+0x1414/0x2020 fs/namespace.c:4209
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount fs/namespace.c:4410 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebcc000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 0 bytes to the right of
 allocated 8192-byte region [ffff88807ebcc000, ffff88807ebce000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebc8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf201 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5569, tgid 5569 (S50crond), ts 71094773892, free_ts 69716881713
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
 tomoyo_init_log+0xc8a/0x2140 security/tomoyo/audit.c:264
 tomoyo_supervisor+0x302/0x13b0 security/tomoyo/common.c:2198
 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
 tomoyo_env_perm+0x191/0x200 security/tomoyo/environ.c:63
 tomoyo_environ security/tomoyo/domain.c:672 [inline]
 tomoyo_find_next_domain+0xec2/0x20b0 security/tomoyo/domain.c:888
 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline]
 tomoyo_bprm_check_security+0x12e/0x1d0 security/tomoyo/tomoyo.c:92
 security_bprm_check+0x1b9/0x1e0 security/security.c:1302
 search_binary_handler fs/exec.c:1655 [inline]
 exec_binprm fs/exec.c:1697 [inline]
 bprm_execve fs/exec.c:1749 [inline]
 bprm_execve+0x810/0x1650 fs/exec.c:1725
 do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1855
page last free pid 5537 tgid 5537 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88807ebcdf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807ebcdf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807ebce000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807ebce080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebce100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebcf000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14385:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4347
 __do_krealloc mm/slub.c:4905 [inline]
 krealloc_noprof+0x156/0x370 mm/slub.c:4958
 bch2_sb_realloc+0x20f/0x590 fs/bcachefs/super-io.c:222
 read_one_super+0x2e0/0x1580 fs/bcachefs/super-io.c:759
 __bch2_read_super+0x4d5/0x1120 fs/bcachefs/super-io.c:851
 bch2_fs_open+0x313/0xc50 fs/bcachefs/super.c:2391
 bch2_fs_get_tree+0xcbe/0x1b20 fs/bcachefs/fs.c:2473
 vfs_get_tree+0x8e/0x340 fs/super.c:1804
 do_new_mount fs/namespace.c:3885 [inline]
 path_mount+0x1414/0x2020 fs/namespace.c:4209
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount fs/namespace.c:4410 [inline]
 __x64_sys_mount+0x28d/0x310 fs/namespace.c:4410
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebcc000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 4096 bytes to the right of
 allocated 8192-byte region [ffff88807ebcc000, ffff88807ebce000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebc8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842280 ffffea0000d82400 dead000000000002
head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf201 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5569, tgid 5569 (S50crond), ts 71094773892, free_ts 69716881713
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
 tomoyo_init_log+0xc8a/0x2140 security/tomoyo/audit.c:264
 tomoyo_supervisor+0x302/0x13b0 security/tomoyo/common.c:2198
 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
 tomoyo_env_perm+0x191/0x200 security/tomoyo/environ.c:63
 tomoyo_environ security/tomoyo/domain.c:672 [inline]
 tomoyo_find_next_domain+0xec2/0x20b0 security/tomoyo/domain.c:888
 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline]
 tomoyo_bprm_check_security+0x12e/0x1d0 security/tomoyo/tomoyo.c:92
 security_bprm_check+0x1b9/0x1e0 security/security.c:1302
 search_binary_handler fs/exec.c:1655 [inline]
 exec_binprm fs/exec.c:1697 [inline]
 bprm_execve fs/exec.c:1749 [inline]
 bprm_execve+0x810/0x1650 fs/exec.c:1725
 do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1855
page last free pid 5537 tgid 5537 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88807ebcef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebcef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807ebcf000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807ebcf080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebcf100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-use-after-free in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-use-after-free in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-use-after-free in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-use-after-free in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebd0000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 vfs_fstatat+0x85/0xf0 fs/stat.c:376
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebd0000
 which belongs to the cache names_cache of size 4096
The buggy address is located 0 bytes inside of
 freed 4096-byte region [ffff88807ebd0000, ffff88807ebd1000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf401 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 5199, tgid 5199 (udevd), ts 360509543199, free_ts 360182122805
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5843 tgid 5843 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195
 __vmf_anon_prepare+0x11c/0x240 mm/memory.c:3523
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_anonymous_page mm/memory.c:5087 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault+0x27f6/0x5490 mm/memory.c:6232
 handle_mm_fault+0x589/0xd10 mm/memory.c:6401
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff88807ebcff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebcff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807ebd0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88807ebd0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:73 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:328 [inline]
BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:249 [inline]
BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
Read of size 4096 at addr ffff88807ebd1000 by task kworker/u8:10/6464

CPU: 0 UID: 0 PID: 6464 Comm: kworker/u8:10 Tainted: G    B               6.16.0-rc2-syzkaller-00087-g24770983ccfe #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: loop0 loop_workfn
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:189
 __asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
 memcpy_from_iter lib/iov_iter.c:73 [inline]
 iterate_bvec include/linux/iov_iter.h:123 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:304 [inline]
 iterate_and_advance include/linux/iov_iter.h:328 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 copy_folio_from_iter_atomic+0xcb0/0x1aa0 lib/iov_iter.c:479
 generic_perform_write+0x22c/0x930 mm/filemap.c:4130
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3463
 lo_rw_aio+0xc58/0x10b0 drivers/block/loop.c:395
 do_req_filebacked drivers/block/loop.c:428 [inline]
 loop_handle_cmd drivers/block/loop.c:1889 [inline]
 loop_process_work+0x139/0x1070 drivers/block/loop.c:1924
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 vfs_fstatat+0xe1/0xf0 fs/stat.c:370
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14372:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4745
 putname+0x154/0x1a0 fs/namei.c:297
 vfs_fstatat+0x85/0xf0 fs/stat.c:376
 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ebd0000
 which belongs to the cache names_cache of size 4096
The buggy address is located 0 bytes to the right of
 allocated 4096-byte region [ffff88807ebd0000, ffff88807ebd1000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ebd0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
raw: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888140409640 ffffea0000ae3800 dead000000000002
head: 0000000000000000 0000000000070007 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001faf401 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 5199, tgid 5199 (udevd), ts 360509543199, free_ts 360182122805
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 do_readlinkat+0xb4/0x3a0 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5843 tgid 5843 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 __anon_vma_prepare+0xae/0x5e0 mm/rmap.c:195
 __vmf_anon_prepare+0x11c/0x240 mm/memory.c:3523
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_anonymous_page mm/memory.c:5087 [inline]
 do_pte_missing mm/memory.c:4249 [inline]
 handle_pte_fault mm/memory.c:6089 [inline]
 __handle_mm_fault+0x27f6/0x5490 mm/memory.c:6232
 handle_mm_fault+0x589/0xd10 mm/memory.c:6401
 do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x5c/0xb0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

Memory state around the buggy address:
 ffff88807ebd0f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ebd0f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807ebd1000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88807ebd1080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807ebd1100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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