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BUG: KASAN: slab-use-after-free in jfs_readdir+0x1152/0x3420 fs/jfs/jfs_dtree.c:2878
Read of size 8 at addr ffff88805be89168 by task syz.3.320/8107

CPU: 0 UID: 0 PID: 8107 Comm: syz.3.320 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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
 jfs_readdir+0x1152/0x3420 fs/jfs/jfs_dtree.c:2878
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:67
 iterate_dir+0x3a5/0x580 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:399 [inline]
 __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384
 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
RIP: 0033:0x7f51e093c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f51deb96028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f51e0bb5fa0 RCX: 00007f51e093c819
RDX: 0000000000000022 RSI: 0000000000000000 RDI: 0000000000000009
RBP: 00007f51e09d2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f51e0bb6038 R14: 00007f51e0bb5fa0 R15: 00007ffff1c46158
 </TASK>

Allocated by task 8107:
 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:4569 [inline]
 slab_alloc_node mm/slub.c:4898 [inline]
 kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4905
 mempool_alloc_noprof+0x1d4/0x300 mm/mempool.c:566
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x50c/0xe20 fs/jfs/jfs_metapage.c:761
 dtReadFirst+0xbb/0x780 fs/jfs/jfs_dtree.c:3076
 dtReadNext fs/jfs/jfs_dtree.c:3157 [inline]
 jfs_readdir+0x8b7/0x3420 fs/jfs/jfs_dtree.c:2871
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:67
 iterate_dir+0x3a5/0x580 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:399 [inline]
 __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384
 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 8107:
 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:6246 [inline]
 kmem_cache_free+0x187/0x6c0 mm/slub.c:6373
 mempool_free+0xf5/0x140 mm/mempool.c:711
 free_metapage fs/jfs/jfs_metapage.c:280 [inline]
 drop_metapage fs/jfs/jfs_metapage.c:317 [inline]
 release_metapage+0x827/0xa90 fs/jfs/jfs_metapage.c:893
 dtReadNext fs/jfs/jfs_dtree.c:3199 [inline]
 jfs_readdir+0xee3/0x3420 fs/jfs/jfs_dtree.c:2871
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:67
 iterate_dir+0x3a5/0x580 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:399 [inline]
 __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384
 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 ffff88805be89138
 which belongs to the cache jfs_mp of size 248
The buggy address is located 48 bytes inside of
 freed 248-byte region [ffff88805be89138, ffff88805be89230)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5be89
flags: 0x80000000000000(node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000000 ffff888140425a00 dead000000000122 0000000000000000
raw: 0000000000000000 00000008000d000d 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5808, tgid 5808 (syz-executor), ts 359624727323, free_ts 359585580991
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3938
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5218
 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:7251
 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]
 kmem_cache_alloc_noprof+0x433/0x680 mm/slub.c:4905
 mempool_alloc_noprof+0x1d4/0x300 mm/mempool.c:566
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x50c/0xe20 fs/jfs/jfs_metapage.c:761
 diSync+0xc4/0x8d0 fs/jfs/jfs_imap.c:216
 diUnmount+0xc8/0x130 fs/jfs/jfs_imap.c:185
 jfs_umount+0x21f/0x3d0 fs/jfs/jfs_umount.c:87
 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646
 kill_block_super+0x44/0x90 fs/super.c:1725
 deactivate_locked_super+0xbc/0x130 fs/super.c:476
page last free pid 7801 tgid 7797 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xfa6/0x10f0 mm/page_alloc.c:2935
 tlb_batch_list_free mm/mmu_gather.c:161 [inline]
 tlb_finish_mmu+0x144/0x230 mm/mmu_gather.c:552
 exit_mmap+0x498/0x9e0 mm/mmap.c:1313
 __mmput+0xcb/0x3d0 kernel/fork.c:1178
 exit_mm+0x18e/0x250 kernel/exit.c:581
 do_exit+0x6a2/0x22c0 kernel/exit.c:963
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
 get_signal+0x125c/0x1310 kernel/signal.c:3037
 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x480 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:238 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
 do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805be89000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805be89080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805be89100: fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb
                                                          ^
 ffff88805be89180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805be89200: fb fb fb fb fb fb fc fc fc fc fc fc fc fc 00 00
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