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BUG: KASAN: slab-use-after-free in txUnlock+0x951/0xde0 fs/jfs/jfs_txnmgr.c:927
Read of size 2 at addr ffff888030b2e0f8 by task jfsCommit/108

CPU: 0 UID: 0 PID: 108 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
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
 txUnlock+0x951/0xde0 fs/jfs/jfs_txnmgr.c:927
 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline]
 jfs_lazycommit+0x59f/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 5327:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4584 [inline]
 slab_alloc_node mm/slub.c:4917 [inline]
 kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4931
 mempool_alloc_noprof+0x1bf/0x300 mm/mempool.c:559
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x4ed/0xdf0 fs/jfs/jfs_metapage.c:761
 diNewExt+0xa53/0x3020 fs/jfs/jfs_imap.c:2275
 diAllocExt fs/jfs/jfs_imap.c:1952 [inline]
 diAllocAG+0xbed/0x1de0 fs/jfs/jfs_imap.c:1669
 diAlloc+0x1e2/0x16b0 fs/jfs/jfs_imap.c:1590
 ialloc+0x8c/0x8e0 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x1e4/0xb00 fs/jfs/namei.c:226
 vfs_mkdir+0x406/0x620 fs/namei.c:5276
 filename_mkdirat+0x285/0x510 fs/namei.c:5309
 __do_sys_mkdirat fs/namei.c:5330 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5327
 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 69:
 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:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kmem_cache_free+0x182/0x650 mm/slub.c:6504
 mempool_free+0xec/0x130 mm/mempool.c:704
 free_metapage fs/jfs/jfs_metapage.c:280 [inline]
 metapage_release_folio+0x462/0x590 fs/jfs/jfs_metapage.c:637
 shrink_folio_list+0x2364/0x5330 mm/vmscan.c:1463
 evict_folios+0x3821/0x4b40 mm/vmscan.c:4835
 try_to_shrink_lruvec+0xb4f/0xed0 mm/vmscan.c:4983
 shrink_one+0x233/0x730 mm/vmscan.c:5024
 shrink_many mm/vmscan.c:5087 [inline]
 lru_gen_shrink_node mm/vmscan.c:5165 [inline]
 shrink_node+0x3303/0x3b60 mm/vmscan.c:6154
 kswapd_shrink_node mm/vmscan.c:7008 [inline]
 balance_pgdat mm/vmscan.c:7186 [inline]
 kswapd+0x17b6/0x31c0 mm/vmscan.c:7462
 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

The buggy address belongs to the object at ffff888030b2e0f8
 which belongs to the cache jfs_mp of size 184
The buggy address is located 0 bytes inside of
 freed 184-byte region [ffff888030b2e0f8, ffff888030b2e1b0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30b2e
flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000000 ffff888030b2c000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000800100010 00000000f5000000 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 8671169913, free_ts 0
 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:3266 [inline]
 allocate_slab+0x79/0x5e0 mm/slub.c:3380
 new_slab mm/slub.c:3426 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 kmem_cache_alloc_noprof+0x382/0x5f0 mm/slub.c:4931
 mempool_init_node+0x1f4/0x4f0 mm/mempool.c:259
 mempool_create_node_noprof+0xb8/0x150 mm/mempool.c:323
 metapage_init+0xed/0x150 fs/jfs/jfs_metapage.c:293
 init_jfs_fs+0xfd/0x4e0 fs/jfs/super.c:969
 do_one_initcall+0x250/0x870 init/main.c:1347
 do_initcall_level+0x10a/0x1a0 init/main.c:1409
 do_initcalls+0x59/0xa0 init/main.c:1425
 kernel_init_freeable+0x29d/0x3e0 init/main.c:1658
 kernel_init+0x1d/0x1d0 init/main.c:1548
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888030b2df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888030b2e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888030b2e080: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa
                                                                ^
 ffff888030b2e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888030b2e180: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb
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