syzbot
KASAN: slab-use-after-free Read in gfs2_remove_from_ail
Status:
moderation: reported on 2026/09/09 15:40
Subsystems:
gfs2
Labels:
prio:high
[Documentation on labels]
Reported-by: syzbot+ca631240154854016d8f@syzkaller.appspotmail.com
First crash: 4d03h, last: 1d16h
Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
Read of size 8 at addr ffff88807c647920 by task kworker/0:6/5768
CPU: 0 UID: 0 PID: 5768 Comm: kworker/0:6 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
Workqueue: events gfs2_withdraw_func
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
__list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
__list_del_entry_valid include/linux/list.h:140 [inline]
__list_del_entry include/linux/list.h:261 [inline]
list_del_init include/linux/list.h:333 [inline]
gfs2_remove_from_ail+0x138/0x340 fs/gfs2/log.c:79
gfs2_ail_empty_tr fs/gfs2/log.c:287 [inline]
gfs2_ail_drain+0x39c/0x6b0 fs/gfs2/log.c:954
do_withdraw+0xeb/0x300 fs/gfs2/util.c:126
gfs2_withdraw_func+0x349/0x3d0 fs/gfs2/util.c:236
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 7723:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010
gfs2_glock_get+0x1e5/0x1260 fs/gfs2/glock.c:1074
gfs2_inode_lookup+0x2e0/0x920 fs/gfs2/inode.c:149
gfs2_lookup_root+0x57/0xe0 fs/gfs2/ops_fstype.c:428
init_sb+0xa17/0xfd0 fs/gfs2/ops_fstype.c:497
gfs2_fill_super+0x1acb/0x2d00 fs/gfs2/ops_fstype.c:1219
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 7773:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6499 [inline]
kmem_cache_free+0x127/0x6c0 mm/slub.c:6626
gfs2_glock_dealloc+0xd0/0x160 fs/gfs2/glock.c:134
rcu_do_batch kernel/rcu/tree.c:2650 [inline]
rcu_core+0x5f0/0x1260 kernel/rcu/tree.c:2919
handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
Last potentially related work creation:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3181
gfs2_glock_free+0x35/0xa0 fs/gfs2/glock.c:150
glock_work_func+0x437/0x4d0 fs/gfs2/glock.c:1003
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Second to last potentially related work creation:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
insert_work+0x36/0x230 kernel/workqueue.c:2272
__queue_work+0xa60/0x1370 kernel/workqueue.c:2448
__queue_delayed_work+0x357/0x450 kernel/workqueue.c:2617
queue_delayed_work_on+0x180/0x1e0 kernel/workqueue.c:2669
queue_delayed_work include/linux/workqueue.h:715 [inline]
gfs2_glock_queue_work+0x75/0x120 fs/gfs2/glock.c:198
do_xmote+0x453/0x680 fs/gfs2/glock.c:718
run_queue+0x555/0x6a0 fs/gfs2/glock.c:757
glock_work_func+0x35b/0x4d0 fs/gfs2/glock.c:987
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
The buggy address belongs to the object at ffff88807c647808
which belongs to the cache gfs2_glock(aspace) of size 1176
The buggy address is located 280 bytes inside of
freed 1176-byte region [ffff88807c647808, ffff88807c647ca0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c644
head: order:2 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 ffff8881404313c0 dead000000000122 0000000000000000
raw: 0000000000000000 00000002000c000c 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff8881404313c0 dead000000000122 0000000000000000
head: 0000000000000000 00000002000c000c 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7723, tgid 7722 (syz.3.658), ts 220778208215
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab mm/slub.c:3462 [inline]
new_slab+0xa9/0x6e0 mm/slub.c:3513
refill_objects+0xe3/0x410 mm/slub.c:7410
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
kmem_cache_alloc_noprof+0x4c4/0x6a0 mm/slub.c:5010
gfs2_glock_get+0x1e5/0x1260 fs/gfs2/glock.c:1074
gfs2_inode_lookup+0x2e0/0x920 fs/gfs2/inode.c:149
gfs2_lookup_root+0x57/0xe0 fs/gfs2/ops_fstype.c:428
init_sb+0xa17/0xfd0 fs/gfs2/ops_fstype.c:497
gfs2_fill_super+0x1acb/0x2d00 fs/gfs2/ops_fstype.c:1219
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
page last free pid 7723 tgid 7722 ts 220636014324 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
stack_depot_save_flags+0x456/0x9f0 lib/stackdepot.c:735
kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_node_noprof+0x30c/0x720 mm/slub.c:5582
_kmalloc_node_noprof include/linux/slab.h:1196 [inline]
alloc_worker kernel/workqueue.c:2755 [inline]
init_rescuer+0x19f/0x550 kernel/workqueue.c:5795
__alloc_workqueue+0xe82/0x1950 kernel/workqueue.c:5993
alloc_workqueue_va kernel/workqueue.c:6033 [inline]
alloc_workqueue_noprof+0xc7/0x130 kernel/workqueue.c:6049
gfs2_fill_super+0x140f/0x2d00 fs/gfs2/ops_fstype.c:1197
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
Memory state around the buggy address:
ffff88807c647800: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807c647880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807c647900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807c647980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807c647a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1a4/0x1d0 lib/list_debug.c:65
Read of size 8 at addr ffff88807c647928 by task kworker/0:6/5768
CPU: 0 UID: 0 PID: 5768 Comm: kworker/0:6 Tainted: G B syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
Workqueue: events gfs2_withdraw_func
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
__list_del_entry_valid_or_report+0x1a4/0x1d0 lib/list_debug.c:65
__list_del_entry_valid include/linux/list.h:140 [inline]
__list_del_entry include/linux/list.h:261 [inline]
list_del_init include/linux/list.h:333 [inline]
gfs2_remove_from_ail+0x138/0x340 fs/gfs2/log.c:79
gfs2_ail_empty_tr fs/gfs2/log.c:287 [inline]
gfs2_ail_drain+0x39c/0x6b0 fs/gfs2/log.c:954
do_withdraw+0xeb/0x300 fs/gfs2/util.c:126
gfs2_withdraw_func+0x349/0x3d0 fs/gfs2/util.c:236
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 7723:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010
gfs2_glock_get+0x1e5/0x1260 fs/gfs2/glock.c:1074
gfs2_inode_lookup+0x2e0/0x920 fs/gfs2/inode.c:149
gfs2_lookup_root+0x57/0xe0 fs/gfs2/ops_fstype.c:428
init_sb+0xa17/0xfd0 fs/gfs2/ops_fstype.c:497
gfs2_fill_super+0x1acb/0x2d00 fs/gfs2/ops_fstype.c:1219
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 7773:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6499 [inline]
kmem_cache_free+0x127/0x6c0 mm/slub.c:6626
gfs2_glock_dealloc+0xd0/0x160 fs/gfs2/glock.c:134
rcu_do_batch kernel/rcu/tree.c:2650 [inline]
rcu_core+0x5f0/0x1260 kernel/rcu/tree.c:2919
handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
Last potentially related work creation:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3181
gfs2_glock_free+0x35/0xa0 fs/gfs2/glock.c:150
glock_work_func+0x437/0x4d0 fs/gfs2/glock.c:1003
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Second to last potentially related work creation:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
insert_work+0x36/0x230 kernel/workqueue.c:2272
__queue_work+0xa60/0x1370 kernel/workqueue.c:2448
__queue_delayed_work+0x357/0x450 kernel/workqueue.c:2617
queue_delayed_work_on+0x180/0x1e0 kernel/workqueue.c:2669
queue_delayed_work include/linux/workqueue.h:715 [inline]
gfs2_glock_queue_work+0x75/0x120 fs/gfs2/glock.c:198
do_xmote+0x453/0x680 fs/gfs2/glock.c:718
run_queue+0x555/0x6a0 fs/gfs2/glock.c:757
glock_work_func+0x35b/0x4d0 fs/gfs2/glock.c:987
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
The buggy address belongs to the object at ffff88807c647808
which belongs to the cache gfs2_glock(aspace) of size 1176
The buggy address is located 288 bytes inside of
freed 1176-byte region [ffff88807c647808, ffff88807c647ca0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c644
head: order:2 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 ffff8881404313c0 dead000000000122 0000000000000000
raw: 0000000000000000 00000002000c000c 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff8881404313c0 dead000000000122 0000000000000000
head: 0000000000000000 00000002000c000c 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7723, tgid 7722 (syz.3.658), ts 220778208215
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab mm/slub.c:3462 [inline]
new_slab+0xa9/0x6e0 mm/slub.c:3513
refill_objects+0xe3/0x410 mm/slub.c:7410
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
kmem_cache_alloc_noprof+0x4c4/0x6a0 mm/slub.c:5010
gfs2_glock_get+0x1e5/0x1260 fs/gfs2/glock.c:1074
gfs2_inode_lookup+0x2e0/0x920 fs/gfs2/inode.c:149
gfs2_lookup_root+0x57/0xe0 fs/gfs2/ops_fstype.c:428
init_sb+0xa17/0xfd0 fs/gfs2/ops_fstype.c:497
gfs2_fill_super+0x1acb/0x2d00 fs/gfs2/ops_fstype.c:1219
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
page last free pid 7723 tgid 7722 ts 220636014324 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
stack_depot_save_flags+0x456/0x9f0 lib/stackdepot.c:735
kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_node_noprof+0x30c/0x720 mm/slub.c:5582
_kmalloc_node_noprof include/linux/slab.h:1196 [inline]
alloc_worker kernel/workqueue.c:2755 [inline]
init_rescuer+0x19f/0x550 kernel/workqueue.c:5795
__alloc_workqueue+0xe82/0x1950 kernel/workqueue.c:5993
alloc_workqueue_va kernel/workqueue.c:6033 [inline]
alloc_workqueue_noprof+0xc7/0x130 kernel/workqueue.c:6049
gfs2_fill_super+0x140f/0x2d00 fs/gfs2/ops_fstype.c:1197
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
Memory state around the buggy address:
ffff88807c647800: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807c647880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807c647900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807c647980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807c647a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in __list_del include/linux/list.h:241 [inline]
BUG: KASAN: slab-use-after-free in __list_del_entry include/linux/list.h:264 [inline]
BUG: KASAN: slab-use-after-free in __list_del_entry include/linux/list.h:259 [inline]
BUG: KASAN: slab-use-after-free in list_del_init include/linux/list.h:333 [inline]
BUG: KASAN: slab-use-after-free in gfs2_remove_from_ail+0x323/0x340 fs/gfs2/log.c:79
Write of size 8 at addr ffff88807c647928 by task kworker/0:6/5768
CPU: 0 UID: 0 PID: 5768 Comm: kworker/0:6 Tainted: G B syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
Workqueue: events gfs2_withdraw_func
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
__list_del include/linux/list.h:241 [inline]
__list_del_entry include/linux/list.h:264 [inline]
__list_del_entry include/linux/list.h:259 [inline]
list_del_init include/linux/list.h:333 [inline]
gfs2_remove_from_ail+0x323/0x340 fs/gfs2/log.c:79
gfs2_ail_empty_tr fs/gfs2/log.c:287 [inline]
gfs2_ail_drain+0x39c/0x6b0 fs/gfs2/log.c:954
do_withdraw+0xeb/0x300 fs/gfs2/util.c:126
gfs2_withdraw_func+0x349/0x3d0 fs/gfs2/util.c:236
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 7723:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010
gfs2_glock_get+0x1e5/0x1260 fs/gfs2/glock.c:1074
gfs2_inode_lookup+0x2e0/0x920 fs/gfs2/inode.c:149
gfs2_lookup_root+0x57/0xe0 fs/gfs2/ops_fstype.c:428
init_sb+0xa17/0xfd0 fs/gfs2/ops_fstype.c:497
gfs2_fill_super+0x1acb/0x2d00 fs/gfs2/ops_fstype.c:1219
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 7773:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6499 [inline]
kmem_cache_free+0x127/0x6c0 mm/slub.c:6626
gfs2_glock_dealloc+0xd0/0x160 fs/gfs2/glock.c:134
rcu_do_batch kernel/rcu/tree.c:2650 [inline]
rcu_core+0x5f0/0x1260 kernel/rcu/tree.c:2919
handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x56/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
Last potentially related work creation:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3181
gfs2_glock_free+0x35/0xa0 fs/gfs2/glock.c:150
glock_work_func+0x437/0x4d0 fs/gfs2/glock.c:1003
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Second to last potentially related work creation:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
insert_work+0x36/0x230 kernel/workqueue.c:2272
__queue_work+0xa60/0x1370 kernel/workqueue.c:2448
__queue_delayed_work+0x357/0x450 kernel/workqueue.c:2617
queue_delayed_work_on+0x180/0x1e0 kernel/workqueue.c:2669
queue_delayed_work include/linux/workqueue.h:715 [inline]
gfs2_glock_queue_work+0x75/0x120 fs/gfs2/glock.c:198
do_xmote+0x453/0x680 fs/gfs2/glock.c:718
run_queue+0x555/0x6a0 fs/gfs2/glock.c:757
glock_work_func+0x35b/0x4d0 fs/gfs2/glock.c:987
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
The buggy address belongs to the object at ffff88807c647808
which belongs to the cache gfs2_glock(aspace) of size 1176
The buggy address is located 288 bytes inside of
freed 1176-byte region [ffff88807c647808, ffff88807c647ca0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c644
head: order:2 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 ffff8881404313c0 dead000000000122 0000000000000000
raw: 0000000000000000 00000002000c000c 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff8881404313c0 dead000000000122 0000000000000000
head: 0000000000000000 00000002000c000c 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7723, tgid 7722 (syz.3.658), ts 220778208215
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab mm/slub.c:3462 [inline]
new_slab+0xa9/0x6e0 mm/slub.c:3513
refill_objects+0xe3/0x410 mm/slub.c:7410
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
kmem_cache_alloc_noprof+0x4c4/0x6a0 mm/slub.c:5010
gfs2_glock_get+0x1e5/0x1260 fs/gfs2/glock.c:1074
gfs2_inode_lookup+0x2e0/0x920 fs/gfs2/inode.c:149
gfs2_lookup_root+0x57/0xe0 fs/gfs2/ops_fstype.c:428
init_sb+0xa17/0xfd0 fs/gfs2/ops_fstype.c:497
gfs2_fill_super+0x1acb/0x2d00 fs/gfs2/ops_fstype.c:1219
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
page last free pid 7723 tgid 7722 ts 220636014324 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
stack_depot_save_flags+0x456/0x9f0 lib/stackdepot.c:735
kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_node_noprof+0x30c/0x720 mm/slub.c:5582
_kmalloc_node_noprof include/linux/slab.h:1196 [inline]
alloc_worker kernel/workqueue.c:2755 [inline]
init_rescuer+0x19f/0x550 kernel/workqueue.c:5795
__alloc_workqueue+0xe82/0x1950 kernel/workqueue.c:5993
alloc_workqueue_va kernel/workqueue.c:6033 [inline]
alloc_workqueue_noprof+0xc7/0x130 kernel/workqueue.c:6049
gfs2_fill_super+0x140f/0x2d00 fs/gfs2/ops_fstype.c:1197
get_tree_bdev_flags+0x38c/0x620 fs/super.c:1887
gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1333
vfs_get_tree+0x92/0x320 fs/super.c:1947
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
Memory state around the buggy address:
ffff88807c647800: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807c647880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807c647900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807c647980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807c647a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Struck through repros no longer work on HEAD.