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BUG: KASAN: slab-use-after-free in lbmIODone+0x1312/0x16c0 fs/jfs/jfs_logmgr.c:2192
Read of size 4 at addr ffff888036f07008 by task ktimers/1/29

CPU: 1 UID: 0 PID: 29 Comm: ktimers/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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
 lbmIODone+0x1312/0x16c0 fs/jfs/jfs_logmgr.c:2192
 blk_update_request+0x57e/0xe60 block/blk-mq.c:1016
 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178
 blk_complete_reqs block/blk-mq.c:1253 [inline]
 blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258
 handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1151
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 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 6554:
 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+0x3a6/0x690 mm/slub.c:5419
 kmalloc_noprof include/linux/slab.h:950 [inline]
 lbmLogInit fs/jfs/jfs_logmgr.c:1819 [inline]
 lmLogInit+0x3e5/0x1a00 fs/jfs/jfs_logmgr.c:1267
 open_inline_log fs/jfs/jfs_logmgr.c:1173 [inline]
 lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1067
 jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257
 jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532
 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x341/0xd30 fs/namespace.c:3834
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6554:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 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:2689 [inline]
 slab_free mm/slub.c:6250 [inline]
 kfree+0x1c5/0x6c0 mm/slub.c:6565
 lbmLogShutdown fs/jfs/jfs_logmgr.c:1862 [inline]
 lmLogShutdown+0x456/0x850 fs/jfs/jfs_logmgr.c:1681
 lmLogClose+0x28a/0x520 fs/jfs/jfs_logmgr.c:1457
 jfs_umount+0x2fb/0x3d0 fs/jfs/jfs_umount.c:124
 jfs_fill_super+0x9c5/0xd80 fs/jfs/super.c:567
 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x341/0xd30 fs/namespace.c:3834
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888036f07000
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 8 bytes inside of
 freed 256-byte region [ffff888036f07000, ffff888036f07100)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x36f06
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88801a010b40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88801a010b40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5267, tgid 5267 (dhcpcd-run-hook), ts 51650273804, free_ts 49728648990
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
 prep_new_page mm/page_alloc.c:1866 [inline]
 get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3467
 new_slab mm/slub.c:3525 [inline]
 refill_objects+0x33c/0x3d0 mm/slub.c:7255
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651
 alloc_from_pcs mm/slub.c:4749 [inline]
 slab_alloc_node mm/slub.c:4883 [inline]
 __kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5414
 kmalloc_noprof include/linux/slab.h:950 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 smk_fetch+0x95/0x140 security/smack/smack_lsm.c:285
 smack_d_instantiate+0x757/0x990 security/smack/smack_lsm.c:3653
 security_d_instantiate+0x106/0x1d0 security/security.c:3704
 d_splice_alias_ops+0x71/0x3e0 fs/dcache.c:3141
 ext4_lookup+0x302/0x710 fs/ext4/namei.c:1812
 __lookup_slow+0x2d2/0x440 fs/namei.c:1915
 lookup_slow+0x53/0x70 fs/namei.c:1932
 walk_component fs/namei.c:2278 [inline]
 lookup_last fs/namei.c:2785 [inline]
 path_lookupat+0x3f5/0x8c0 fs/namei.c:2809
 filename_lookup+0x256/0x5d0 fs/namei.c:2838
page last free pid 20 tgid 20 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 __free_frozen_pages+0xfa6/0x10f0 mm/page_alloc.c:2943
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core kernel/rcu/tree.c:2869 [inline]
 rcu_cpu_kthread+0x99e/0x1470 kernel/rcu/tree.c:2957
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 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

Memory state around the buggy address:
 ffff888036f06f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888036f06f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888036f07000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888036f07080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888036f07100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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