==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: use-after-free in atomic_inc include/linux/atomic/atomic-instrumented.h:181 [inline]
BUG: KASAN: use-after-free in kernfs_get+0x5e/0x90 fs/kernfs/dir.c:505
Write of size 4 at addr ffff888120f9a3e8 by task kworker/0:5/556
CPU: 0 PID: 556 Comm: kworker/0:5 Not tainted 5.15.183-syzkaller-00056-g56993594bfa4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events flush_stashed_error_work
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:88
dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:427 [inline]
kasan_report+0xf1/0x140 mm/kasan/report.c:444
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x280/0x290 mm/kasan/generic.c:189
__kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
atomic_inc include/linux/atomic/atomic-instrumented.h:181 [inline]
kernfs_get+0x5e/0x90 fs/kernfs/dir.c:505
sysfs_notify+0x5a/0xd0 fs/sysfs/file.c:190
ext4_notify_error_sysfs+0x25/0x30 fs/ext4/sysfs.c:516
flush_stashed_error_work+0x2d5/0x2f0 fs/ext4/super.c:-1
process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
kthread+0x411/0x500 kernel/kthread.c:337
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Allocated by task 13141:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:433 [inline]
__kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466
kasan_slab_alloc include/linux/kasan.h:217 [inline]
slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
slab_alloc_node mm/slub.c:3240 [inline]
slab_alloc mm/slub.c:3250 [inline]
kmem_cache_alloc+0xf7/0x260 mm/slub.c:3255
kmem_cache_zalloc include/linux/slab.h:737 [inline]
__kernfs_new_node+0xdb/0x680 fs/kernfs/dir.c:593
kernfs_new_node+0x150/0x260 fs/kernfs/dir.c:669
kernfs_create_dir_ns+0x47/0x130 fs/kernfs/dir.c:1017
sysfs_create_dir_ns+0x11c/0x280 fs/sysfs/dir.c:59
create_dir lib/kobject.c:89 [inline]
kobject_add_internal+0x755/0xda0 lib/kobject.c:263
kobject_add_varg lib/kobject.c:398 [inline]
kobject_init_and_add+0x122/0x190 lib/kobject.c:481
ext4_register_sysfs+0xbb/0x2c0 fs/ext4/sysfs.c:529
ext4_fill_super+0x863b/0x9030 fs/ext4/super.c:4941
mount_bdev+0x2ae/0x3e0 fs/super.c:1400
ext4_mount+0x34/0x40 fs/ext4/super.c:6618
legacy_get_tree+0xed/0x190 fs/fs_context.c:611
vfs_get_tree+0x89/0x260 fs/super.c:1530
do_new_mount+0x25a/0xa20 fs/namespace.c:3014
path_mount+0x675/0x1020 fs/namespace.c:3344
do_mount fs/namespace.c:3357 [inline]
__do_sys_mount fs/namespace.c:3565 [inline]
__se_sys_mount+0x318/0x380 fs/namespace.c:3542
__x64_sys_mount+0xbf/0xd0 fs/namespace.c:3542
x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
Freed by task 7550:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365
__kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
kasan_slab_free include/linux/kasan.h:193 [inline]
slab_free_hook mm/slub.c:1723 [inline]
slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1749
slab_free mm/slub.c:3521 [inline]
kmem_cache_free+0x100/0x320 mm/slub.c:3539
kernfs_put+0x310/0x480 fs/kernfs/dir.c:547
sysfs_put include/linux/sysfs.h:641 [inline]
__kobject_del+0xf8/0x2f0 lib/kobject.c:629
kobject_del+0x45/0x60 lib/kobject.c:651
ext4_unregister_sysfs+0x91/0xa0 fs/ext4/sysfs.c:563
ext4_put_super+0x70/0xa70 fs/ext4/super.c:1183
generic_shutdown_super+0x151/0x330 fs/super.c:475
kill_block_super+0x7f/0xf0 fs/super.c:1427
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x446/0x500 fs/namespace.c:1143
__cleanup_mnt+0x19/0x20 fs/namespace.c:1150
task_work_run+0x127/0x190 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
The buggy address belongs to the object at ffff888120f9a3e8
which belongs to the cache kernfs_node_cache of size 136
The buggy address is located 0 bytes inside of
136-byte region [ffff888120f9a3e8, ffff888120f9a470)
The buggy address belongs to the page:
page:ffffea000483e680 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x120f9a
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 ffffea0004572e80 0000000a0000000a ffff8881001c4780
raw: 0000000000000000 0000000000140014 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 10329, ts 2524950421606, free_ts 2524690637811
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485
__alloc_pages+0x18f/0x440 mm/page_alloc.c:5781
alloc_slab_page mm/slub.c:-1 [inline]
allocate_slab mm/slub.c:1932 [inline]
new_slab+0xa1/0x4d0 mm/slub.c:1995
___slab_alloc+0x381/0x810 mm/slub.c:3028
__slab_alloc+0x49/0x90 mm/slub.c:3115
slab_alloc_node mm/slub.c:3206 [inline]
slab_alloc mm/slub.c:3250 [inline]
kmem_cache_alloc+0x138/0x260 mm/slub.c:3255
kmem_cache_zalloc include/linux/slab.h:737 [inline]
__kernfs_new_node+0xdb/0x680 fs/kernfs/dir.c:593
kernfs_new_node+0x150/0x260 fs/kernfs/dir.c:669
__kernfs_create_file+0x4e/0x270 fs/kernfs/file.c:987
sysfs_add_file_mode_ns+0x29a/0x350 fs/sysfs/file.c:317
create_files fs/sysfs/group.c:64 [inline]
internal_create_group+0x489/0xcf0 fs/sysfs/group.c:149
internal_create_groups fs/sysfs/group.c:189 [inline]
sysfs_create_groups+0x58/0x120 fs/sysfs/group.c:215
device_add_groups drivers/base/core.c:2501 [inline]
device_add_attrs+0x8c/0x700 drivers/base/core.c:2649
device_add+0x5e3/0xed0 drivers/base/core.c:3373
page last free stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
free_pages_prepare mm/page_alloc.c:1472 [inline]
free_pcp_prepare mm/page_alloc.c:1544 [inline]
free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534
free_unref_page+0xa2/0x550 mm/page_alloc.c:3616
free_the_page mm/page_alloc.c:805 [inline]
__free_pages+0x6c/0x100 mm/page_alloc.c:5857
free_pages+0x82/0x90 mm/page_alloc.c:5868
tlb_batch_list_free mm/mmu_gather.c:61 [inline]
tlb_finish_mmu+0x248/0x300 mm/mmu_gather.c:341
exit_mmap+0x40f/0x860 mm/mmap.c:3236
__mmput+0x93/0x320 kernel/fork.c:1180
mmput+0x50/0x150 kernel/fork.c:1203
exit_mm kernel/exit.c:554 [inline]
do_exit+0x9ca/0x27a0 kernel/exit.c:867
do_group_exit+0x141/0x310 kernel/exit.c:1002
__do_sys_exit_group kernel/exit.c:1013 [inline]
__se_sys_exit_group kernel/exit.c:1011 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1011
x64_sys_call+0x832/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
Memory state around the buggy address:
ffff888120f9a280: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
ffff888120f9a300: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb
>ffff888120f9a380: fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb fb
^
ffff888120f9a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
ffff888120f9a480: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb
==================================================================
general protection fault, probably for non-canonical address 0xfbaffc27a00003b9: 0000 [#1] PREEMPT SMP KASAN
KASAN: maybe wild-memory-access in range [0xdd80013d00001dc8-0xdd80013d00001dcf]
CPU: 0 PID: 556 Comm: kworker/0:5 Tainted: G B 5.15.183-syzkaller-00056-g56993594bfa4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events flush_stashed_error_work
RIP: 0010:kernfs_root fs/kernfs/kernfs-internal.h:50 [inline]
RIP: 0010:kernfs_find_and_get_ns+0x54/0x110 fs/kernfs/dir.c:884
Code: 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 33 a3 d8 ff 49 8b 5c 24 08 48 85 db 49 0f 44 dc 48 83 c3 50 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 0d a3 d8 ff 48 8b 1b 48 83 c3 68
RSP: 0018:ffffc90000c8fc60 EFLAGS: 00010a03
RAX: 1bb00027a00003b9 RBX: dd80013d00001dce RCX: ffffffff81ce71bd
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888120f9a3f0
RBP: ffffc90000c8fc88 R08: 0000000000000004 R09: 0000000000000003
R10: fffffbfff0e1764c R11: 1ffffffff0e1764c R12: ffff888120f9a3e8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff854f0260
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3351eff8 CR3: 000000013bd89000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kernfs_find_and_get include/linux/kernfs.h:574 [inline]
sysfs_notify+0x71/0xd0 fs/sysfs/file.c:193
ext4_notify_error_sysfs+0x25/0x30 fs/ext4/sysfs.c:516
flush_stashed_error_work+0x2d5/0x2f0 fs/ext4/super.c:-1
process_one_work+0x6be/0xba0 kernel/workqueue.c:2325
worker_thread+0xa59/0x1200 kernel/workqueue.c:2472
kthread+0x411/0x500 kernel/kthread.c:337
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Modules linked in:
---[ end trace 8a8cbc8e48996fa2 ]---
RIP: 0010:kernfs_root fs/kernfs/kernfs-internal.h:50 [inline]
RIP: 0010:kernfs_find_and_get_ns+0x54/0x110 fs/kernfs/dir.c:884
Code: 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74 05 e8 33 a3 d8 ff 49 8b 5c 24 08 48 85 db 49 0f 44 dc 48 83 c3 50 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 0d a3 d8 ff 48 8b 1b 48 83 c3 68
RSP: 0018:ffffc90000c8fc60 EFLAGS: 00010a03
RAX: 1bb00027a00003b9 RBX: dd80013d00001dce RCX: ffffffff81ce71bd
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff888120f9a3f0
RBP: ffffc90000c8fc88 R08: 0000000000000004 R09: 0000000000000003
R10: fffffbfff0e1764c R11: 1ffffffff0e1764c R12: ffff888120f9a3e8
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff854f0260
FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe5b5f4e178 CR3: 000000011d6c2000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 48 89 f8 mov %rdi,%rax
3: 48 c1 e8 03 shr $0x3,%rax
7: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1)
c: 74 05 je 0x13
e: e8 33 a3 d8 ff call 0xffd8a346
13: 49 8b 5c 24 08 mov 0x8(%r12),%rbx
18: 48 85 db test %rbx,%rbx
1b: 49 0f 44 dc cmove %r12,%rbx
1f: 48 83 c3 50 add $0x50,%rbx
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 0d a3 d8 ff call 0xffd8a346
39: 48 8b 1b mov (%rbx),%rbx
3c: 48 83 c3 68 add $0x68,%rbx