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BUG: KASAN: slab-use-after-free in jfs_readdir+0x118f/0x3ae0 fs/jfs/jfs_dtree.c:2881
Read of size 8 at addr ffff88803ee31648 by task syz.2.76/6268

CPU: 1 UID: 0 PID: 6268 Comm: syz.2.76 Tainted: G        W           6.17.0-rc1-syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 jfs_readdir+0x118f/0x3ae0 fs/jfs/jfs_dtree.c:2881
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x3a2/0x580 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:410 [inline]
 __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6595fbebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6594226038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f65961e5fa0 RCX: 00007f6595fbebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007f6596041e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f65961e6038 R14: 00007f65961e5fa0 R15: 00007ffc5961e1a8
 </TASK>

Allocated by task 6268:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:330 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x143/0x310 mm/slub.c:4236
 mempool_alloc_noprof+0x1a0/0x4e0 mm/mempool.c:406
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x509/0xde0 fs/jfs/jfs_metapage.c:760
 dtSplitRoot+0x202/0x16c0 fs/jfs/jfs_dtree.c:1910
 dtSplitUp fs/jfs/jfs_dtree.c:993 [inline]
 dtInsert+0xef8/0x5f40 fs/jfs/jfs_dtree.c:871
 jfs_mkdir+0x6ec/0xa70 fs/jfs/namei.c:270
 vfs_mkdir+0x306/0x510 fs/namei.c:4366
 do_mkdirat+0x247/0x590 fs/namei.c:4399
 __do_sys_mkdirat fs/namei.c:4416 [inline]
 __se_sys_mkdirat fs/namei.c:4414 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6268:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:243 [inline]
 __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x195/0x510 mm/slub.c:4782
 free_metapage fs/jfs/jfs_metapage.c:279 [inline]
 drop_metapage fs/jfs/jfs_metapage.c:316 [inline]
 release_metapage+0x84c/0xab0 fs/jfs/jfs_metapage.c:892
 dtReadNext fs/jfs/jfs_dtree.c:3202 [inline]
 jfs_readdir+0xece/0x3ae0 fs/jfs/jfs_dtree.c:2874
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x3a2/0x580 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:410 [inline]
 __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803ee31618
 which belongs to the cache jfs_mp of size 248
The buggy address is located 48 bytes inside of
 freed 248-byte region [ffff88803ee31618, ffff88803ee31710)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3ee31
flags: 0x80000000000000(node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000000 ffff8881476f9500 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 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 5993, tgid 5992 (syz.4.5), ts 118862014431, free_ts 118851803709
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x2119/0x21b0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0x8d1/0xdd0 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 kmem_cache_alloc_noprof+0xe6/0x310 mm/slub.c:4236
 mempool_alloc_noprof+0x1a0/0x4e0 mm/mempool.c:406
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x509/0xde0 fs/jfs/jfs_metapage.c:760
 diReadSpecial+0x25b/0x710 fs/jfs/jfs_imap.c:447
 jfs_mount+0x73/0x870 fs/jfs/jfs_mount.c:87
 jfs_fill_super+0x6bc/0xd80 fs/jfs/super.c:523
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
 vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4321
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:1395 [inline]
 __free_frozen_pages+0xb59/0xce0 mm/page_alloc.c:2895
 pagetable_free include/linux/mm.h:2898 [inline]
 pagetable_dtor_free include/linux/mm.h:2996 [inline]
 __tlb_remove_table+0x2d2/0x3b0 include/asm-generic/tlb.h:220
 __tlb_remove_table_free mm/mmu_gather.c:227 [inline]
 tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core kernel/rcu/tree.c:2861 [inline]
 rcu_cpu_kthread+0xbf6/0x1b50 kernel/rcu/tree.c:2949
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88803ee31500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88803ee31580: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
>ffff88803ee31600: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff88803ee31680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803ee31700: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb
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