syzbot

==================================================================
BUG: KASAN: slab-use-after-free in ocfs2_replay_truncate_records fs/ocfs2/alloc.c:5967 [inline]
BUG: KASAN: slab-use-after-free in __ocfs2_flush_truncate_log+0x684/0xf6c fs/ocfs2/alloc.c:6062
Read of size 4 at addr ffff0000e1468ac0 by task syz-executor/6661

CPU: 0 UID: 0 PID: 6661 Comm: syz-executor Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xa8/0x238 mm/kasan/report.c:378
 print_report+0x68/0x84 mm/kasan/report.c:482
 kasan_report+0xb0/0x110 mm/kasan/report.c:595
 __asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380
 ocfs2_replay_truncate_records fs/ocfs2/alloc.c:5967 [inline]
 __ocfs2_flush_truncate_log+0x684/0xf6c fs/ocfs2/alloc.c:6062
 ocfs2_flush_truncate_log+0x4c/0x6c fs/ocfs2/alloc.c:6084
 ocfs2_sync_fs+0xf8/0x2a4 fs/ocfs2/super.c:406
 sync_filesystem+0x1a0/0x218 fs/sync.c:66
 generic_shutdown_super+0x70/0x2b8 fs/super.c:621
 kill_block_super+0x44/0x90 fs/super.c:1722
 deactivate_locked_super+0xc4/0x12c fs/super.c:473
 deactivate_super+0xe0/0x100 fs/super.c:506
 cleanup_mnt+0x31c/0x3ac fs/namespace.c:1327
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1334
 task_work_run+0x1dc/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xfc/0x178 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:103 [inline]
 el0_svc+0x170/0x254 arch/arm64/kernel/entry-common.c:747
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Allocated by task 6553:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:77
 kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:573
 unpoison_slab_object mm/kasan/common.c:342 [inline]
 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:368
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4955 [inline]
 slab_alloc_node mm/slub.c:5265 [inline]
 kmem_cache_alloc_noprof+0x338/0x648 mm/slub.c:5272
 sigqueue_alloc kernel/signal.c:455 [inline]
 __send_signal_locked+0x1e8/0xc5c kernel/signal.c:1087
 send_signal_locked+0xac/0x854 kernel/signal.c:1216
 do_send_sig_info kernel/signal.c:1269 [inline]
 do_send_specific+0x19c/0x2cc kernel/signal.c:4133
 do_tkill kernel/signal.c:4154 [inline]
 __do_sys_tgkill kernel/signal.c:4173 [inline]
 __se_sys_tgkill kernel/signal.c:4167 [inline]
 __arm64_sys_tgkill+0x12c/0x188 kernel/signal.c:4167
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:746
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Freed by task 6550:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:77
 __kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2523 [inline]
 slab_free mm/slub.c:6611 [inline]
 kmem_cache_free+0x18c/0x6dc mm/slub.c:6721
 __sigqueue_free kernel/signal.c:475 [inline]
 collect_signal kernel/signal.c:587 [inline]
 __dequeue_signal+0x3b8/0x4bc kernel/signal.c:609
 dequeue_signal+0x110/0x308 kernel/signal.c:629
 get_signal+0x41c/0x12f8 kernel/signal.c:2914
 arch_do_signal_or_restart+0x1c0/0x4414 arch/arm64/kernel/signal.c:1619
 exit_to_user_mode_loop+0x7c/0x178 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:103 [inline]
 el0_svc+0x170/0x254 arch/arm64/kernel/entry-common.c:747
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

The buggy address belongs to the object at ffff0000e1468a80
 which belongs to the cache sigqueue of size 80
The buggy address is located 64 bytes inside of
 freed 80-byte region [ffff0000e1468a80, ffff0000e1468ad0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x121468
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 05ffc00000000000 ffff0000c18b9500 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000240024 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000e1468980: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fc fc
 ffff0000e1468a00: fc fc fa fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff0000e1468a80: fa fb fb fb fb fb fb fb fb fb fc fc fc fc fa fb
                                           ^
 ffff0000e1468b00: fb fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb
 ffff0000e1468b80: fb fb fb fb fb fb fc fc fc fc fa fb fb fb fb fb
==================================================================
(syz-executor,6661,1):ocfs2_read_blocks:239 ERROR: status = -12
(syz-executor,6661,1):_ocfs2_free_suballoc_bits:2579 ERROR: status = -12
(syz-executor,6661,1):_ocfs2_free_clusters:2676 ERROR: status = -12
(syz-executor,6661,1):ocfs2_replay_truncate_records:5984 ERROR: status = -12
(syz-executor,6661,1):__ocfs2_flush_truncate_log:6065 ERROR: status = -12
(syz-executor,6661,1):ocfs2_sync_fs:408 ERROR: status = -12
(syz-executor,6661,1):ocfs2_read_blocks:239 ERROR: status = -12
(syz-executor,6661,1):_ocfs2_free_suballoc_bits:2579 ERROR: status = -12
(syz-executor,6661,1):_ocfs2_free_clusters:2676 ERROR: status = -12
(syz-executor,6661,1):ocfs2_replay_truncate_records:5984 ERROR: status = -12
(syz-executor,6661,1):__ocfs2_flush_truncate_log:6065 ERROR: status = -12
(syz-executor,6661,1):ocfs2_truncate_log_shutdown:6345 ERROR: status = -12
ocfs2: Unmounting device (7,0) on (node local)