[syzbot] [jfs?] KASAN: slab-use-after-free Write in lmLogSync

[syzbot] [jfs?] KASAN: slab-use-after-free Write in lmLogSync

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    6a97c4d5262d Merge tag 'for-linus' of git://git.kernel.org..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10c04d36580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=67ffb7a3dae3b364
dashboard link: https://syzkaller.appspot.com/bug?extid=ea7ed3bb2f444cb4dfeb
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/27fccab6d587/disk-6a97c4d5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4e2627cdbafb/vmlinux-6a97c4d5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/061ff801444b/bzImage-6a97c4d5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ea7ed3bb2f444cb4dfeb@syzkaller.appspotmail.com

 ... Log Wrap ... Log Wrap ... Log Wrap ...
==================================================================
BUG: KASAN: slab-use-after-free in lmLogSync+0x794/0x7b0 fs/jfs/jfs_logmgr.c:1003
Write of size 4 at addr ffff88807d709218 by task jfsCommit/117

CPU: 0 UID: 0 PID: 117 Comm: jfsCommit Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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/0x1d0 mm/kasan/report.c:595
 lmLogSync+0x794/0x7b0 fs/jfs/jfs_logmgr.c:1003
 jfs_syncpt+0x89/0xa0 fs/jfs/jfs_logmgr.c:1039
 txEnd+0x318/0x490 fs/jfs/jfs_txnmgr.c:551
 txLazyCommit fs/jfs/jfs_txnmgr.c:2686 [inline]
 jfs_lazycommit+0x748/0xab0 fs/jfs/jfs_txnmgr.c:2735
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 15951:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 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
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 open_inline_log fs/jfs/jfs_logmgr.c:1157 [inline]
 lmLogOpen+0x571/0x1360 fs/jfs/jfs_logmgr.c:1067
 jfs_mount_rw+0x2e0/0x690 fs/jfs/jfs_mount.c:257
 jfs_fill_super+0xbc0/0xf50 fs/jfs/super.c:532
 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
 vfs_get_tree+0x92/0x320 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount fs/namespace.c:3834 [inline]
 path_mount+0x7d0/0x23d0 fs/namespace.c:4154
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount fs/namespace.c:4360 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0x860 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10281:
 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:2689 [inline]
 slab_free mm/slub.c:6251 [inline]
 kfree+0x223/0x6c0 mm/slub.c:6566
 lmLogClose+0x55f/0x6f0 fs/jfs/jfs_logmgr.c:1458
 jfs_umount+0x30c/0x430 fs/jfs/jfs_umount.c:124
 jfs_put_super+0x88/0x1a0 fs/jfs/super.c:194
 generic_shutdown_super+0x167/0x360 fs/super.c:646
 kill_block_super+0x3b/0xa0 fs/super.c:1725
 deactivate_locked_super+0xc1/0x1b0 fs/super.c:476
 deactivate_super fs/super.c:509 [inline]
 deactivate_super+0xe7/0x110 fs/super.c:505
 cleanup_mnt+0x21f/0x450 fs/namespace.c:1312
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0x107/0x4f0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x706/0x860 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807d709000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 536 bytes inside of
 freed 1024-byte region [ffff88807d709000, ffff88807d709400)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807d70d000 pfn:0x7d708
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88813fe34dc0 ffffea0001ddac10 ffffea0001e99e10
raw: ffff88807d70d000 000000080010000e 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe34dc0 ffffea0001ddac10 ffffea0001e99e10
head: ffff88807d70d000 000000080010000e 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5636, tgid 5636 (syz-executor), ts 92244588377, free_ts 92228867410
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1858
 prep_new_page mm/page_alloc.c:1866 [inline]
 get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab mm/slub.c:3467 [inline]
 new_slab+0xa6/0x6c0 mm/slub.c:3525
 refill_objects+0x277/0x420 mm/slub.c:7272
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x375/0x650 mm/slub.c:4652
 alloc_from_pcs mm/slub.c:4750 [inline]
 slab_alloc_node mm/slub.c:4884 [inline]
 __do_kmalloc_node mm/slub.c:5295 [inline]
 __kvmalloc_node_noprof+0x7da/0xa00 mm/slub.c:6833
 bucket_table_alloc.isra.0+0x88/0x460 lib/rhashtable.c:194
 rhashtable_init_noprof+0x43b/0x890 lib/rhashtable.c:1108
 ipc_init_ids+0x92/0x280 ipc/util.c:120
 create_ipc_ns ipc/namespace.c:89 [inline]
 copy_ipcs+0x5c8/0x7e0 ipc/namespace.c:116
 create_new_namespaces+0x20a/0xac0 kernel/nsproxy.c:112
 unshare_nsproxy_namespaces+0xf2/0x220 kernel/nsproxy.c:234
 ksys_unshare+0x438/0xab0 kernel/fork.c:3243
 __do_sys_unshare kernel/fork.c:3317 [inline]
 __se_sys_unshare kernel/fork.c:3315 [inline]
 __x64_sys_unshare+0x31/0x40 kernel/fork.c:3315
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0x860 arch/x86/entry/syscall_64.c:94
page last free pid 5646 tgid 5646 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 __free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4570 [inline]
 slab_alloc_node mm/slub.c:4899 [inline]
 __kmalloc_cache_noprof+0x243/0x6f0 mm/slub.c:5415
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 hci_chan_create+0xa6/0x410 net/bluetooth/hci_conn.c:2874
 l2cap_conn_add.part.0+0x1a/0xb00 net/bluetooth/l2cap_core.c:6997
 l2cap_conn_add net/bluetooth/l2cap_core.c:69 [inline]
 l2cap_connect_cfm+0x43e/0xf80 net/bluetooth/l2cap_core.c:7378
 hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline]
 le_conn_complete_evt+0x197c/0x1f60 net/bluetooth/hci_event.c:5865
 hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5891
 hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7529
 hci_event_func net/bluetooth/hci_event.c:7793 [inline]
 hci_event_packet+0x51c/0xcd0 net/bluetooth/hci_event.c:7847
 hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
 process_scheduled_works kernel/workqueue.c:3397 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
 kthread+0x370/0x450 kernel/kthread.c:436

Memory state around the buggy address:
 ffff88807d709100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d709180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807d709200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88807d709280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d709300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
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If the report is already addressed, let syzbot know by replying with:
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If you want to overwrite report's subsystems, reply with:
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
#syz undup

[PATCH] jfs: fix use-after-free in lmLogSync during unmount

[Jie Wang]

jfs_flush_journal(log, 2) waits for log->cqueue and log->synclist to
drain, but lazy commit transactions already moved to the global
TxAnchor.unlock_queue are not accounted for. The jfsCommit thread may
still be processing these through txEnd -> jfs_syncpt -> lmLogSync
after lmLogClose frees the log structure.

Fix by adding wait_event() in lmLogClose before kfree(log) to ensure
log->active has dropped to zero and log_SYNCBARRIER is clear. Add a
corresponding wakeup in txEnd when log->active reaches zero.

Reported-by: syzbot+ea7ed3bb2f444cb4dfeb@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=ea7ed3bb2f444cb4dfeb
Signed-off-by: Jie Wang <jie.wang@intel.com>
---
 fs/jfs/jfs_logmgr.c | 6 ++++++
 fs/jfs/jfs_txnmgr.c | 3 +++
 2 files changed, 9 insertions(+)

diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
index 306165e61438..9977c1359dbc 100644
--- a/fs/jfs/jfs_logmgr.c
+++ b/fs/jfs/jfs_logmgr.c
@@ -1454,6 +1454,9 @@ int lmLogClose(struct super_block *sb)
 		/*
 		 *	in-line log in host file system
 		 */
+		/* wait for lazy commit thread to finish txEnd() */
+		wait_event(log->syncwait, !log->active &&
+			   !test_bit(log_SYNCBARRIER, &log->flag));
 		rc = lmLogShutdown(log);
 		kfree(log);
 		goto out;
@@ -1478,6 +1481,9 @@ int lmLogClose(struct super_block *sb)
 	/*
 	 *	external log as separate logical volume
 	 */
+	/* wait for lazy commit thread to finish txEnd() */
+	wait_event(log->syncwait, !log->active &&
+		   !test_bit(log_SYNCBARRIER, &log->flag));
 	list_del(&log->journal_list);
 	bdev_file = log->bdev_file;
 	rc = lmLogShutdown(log);
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index 083dbbb0c326..75d5c2a10600 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -560,6 +560,9 @@ void txEnd(tid_t tid)
 
 			goto wakeup;
 		}
+
+		/* wakeup lmLogClose waiting for all txn completion */
+		TXN_WAKEUP(&log->syncwait);
 	}
 
 	TXN_UNLOCK();
-- 
2.34.1

Re: [syzbot] [jfs?] KASAN: slab-use-after-free Write in lmLogSync

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    ab9de95c9cf9 Merge tag 'rust-7.2-2' of git://git.kernel.or..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11e27046580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=86ba763b42fa66a
dashboard link: https://syzkaller.appspot.com/bug?extid=ea7ed3bb2f444cb4dfeb
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=109b430e580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c16df342a923/disk-ab9de95c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ddf00a828178/vmlinux-ab9de95c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f468c716a7be/bzImage-ab9de95c.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/410234fc5bd7/mount_0.gz
  fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=13bc540a580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ea7ed3bb2f444cb4dfeb@syzkaller.appspotmail.com

 ... Log Wrap ... Log Wrap ... Log Wrap ...
==================================================================
BUG: KASAN: slab-use-after-free in lmLogSync+0x9a5/0xa40 fs/jfs/jfs_logmgr.c:1003
Write of size 4 at addr ffff888078b39a18 by task jfsCommit/119

CPU: 1 UID: 0 PID: 119 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 lmLogSync+0x9a5/0xa40 fs/jfs/jfs_logmgr.c:1003
 jfs_syncpt+0x7b/0x90 fs/jfs/jfs_logmgr.c:1039
 txEnd+0x2e5/0x530 fs/jfs/jfs_txnmgr.c:551
 txLazyCommit fs/jfs/jfs_txnmgr.c:2686 [inline]
 jfs_lazycommit+0x5d6/0xac0 fs/jfs/jfs_txnmgr.c:2735
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 6176:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x32d/0x660 mm/slub.c:5515
 _kmalloc_noprof include/linux/slab.h:969 [inline]
 _kzalloc_noprof include/linux/slab.h:1290 [inline]
 open_inline_log fs/jfs/jfs_logmgr.c:1157 [inline]
 lmLogOpen+0x2d1/0xf90 fs/jfs/jfs_logmgr.c:1067
 jfs_mount_rw+0xf3/0x670 fs/jfs/jfs_mount.c:257
 jfs_fill_super+0x769/0xda0 fs/jfs/super.c:533
 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1634
 vfs_get_tree+0x92/0x2a0 fs/super.c:1694
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3765 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3841
 do_mount fs/namespace.c:4174 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4367
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5770:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2705 [inline]
 slab_free mm/slub.c:6405 [inline]
 kfree+0x1c5/0x640 mm/slub.c:6720
 lmLogClose+0x296/0x530 fs/jfs/jfs_logmgr.c:-1
 jfs_umount+0x2da/0x3b0 fs/jfs/jfs_umount.c:124
 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x13d/0x2d0 fs/super.c:647
 kill_block_super+0x44/0x90 fs/super.c:1665
 deactivate_locked_super+0xbc/0x130 fs/super.c:477
 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888078b39800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 536 bytes inside of
 freed 1024-byte region [ffff888078b39800, ffff888078b39c00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x78b38
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 ffff88813fe25dc0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fe25dc0 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6055, tgid 6055 (kworker/u8:2), ts 107606662230, free_ts 107579789139
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3294 [inline]
 allocate_slab+0x79/0x5e0 mm/slub.c:3408
 new_slab mm/slub.c:3454 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7338
 refill_sheaf mm/slub.c:2832 [inline]
 __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4703
 alloc_from_pcs mm/slub.c:4801 [inline]
 slab_alloc_node mm/slub.c:4933 [inline]
 __do_kmalloc_node mm/slub.c:5361 [inline]
 __kmalloc_noprof+0x485/0x720 mm/slub.c:5387
 _kmalloc_noprof include/linux/slab.h:973 [inline]
 load_elf_phdrs fs/binfmt_elf.c:540 [inline]
 load_elf_binary+0x2c3/0x2950 fs/binfmt_elf.c:869
 search_binary_handler fs/exec.c:1694 [inline]
 exec_binprm fs/exec.c:1726 [inline]
 bprm_execve+0x9c7/0x1630 fs/exec.c:1778
 kernel_execve+0x8c3/0x9c0 fs/exec.c:1922
 call_usermodehelper_exec_async+0x20f/0x360 kernel/umh.c:109
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page last free pid 4986 tgid 4986 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950
 __slab_free+0x274/0x2c0 mm/slub.c:5767
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4612 [inline]
 slab_alloc_node mm/slub.c:4945 [inline]
 kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4959
 alloc_filename fs/namei.c:147 [inline]
 do_getname+0x2e/0x250 fs/namei.c:187
 class_filename_flags_constructor include/linux/fs.h:2561 [inline]
 do_readlinkat+0xc8/0x510 fs/stat.c:569
 __do_sys_readlink fs/stat.c:605 [inline]
 __se_sys_readlink fs/stat.c:602 [inline]
 __x64_sys_readlink+0x7f/0x90 fs/stat.c:602
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888078b39900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888078b39980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888078b39a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888078b39a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888078b39b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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