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BUG: KASAN: slab-use-after-free in jfs_readdir+0x118c/0x3ae0 fs/jfs/jfs_dtree.c:2881
Read of size 8 at addr ffff88807e49bdc0 by task syz.5.1817/13928

CPU: 1 UID: 0 PID: 13928 Comm: syz.5.1817 Not tainted 6.16.0-syzkaller-08685-g260f6f4fda93 #0 PREEMPT(full) 
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+0x118c/0x3ae0 fs/jfs/jfs_dtree.c:2881
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x5af/0x770 fs/readdir.c:108
 __do_sys_getdents fs/readdir.c:326 [inline]
 __se_sys_getdents+0xe4/0x250 fs/readdir.c:312
 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: 0033:0x7f380a18eb69
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:00007f380afd7038 EFLAGS: 00000246 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007f380a3b5fa0 RCX: 00007f380a18eb69
RDX: 0000000000000022 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00007f380a211df1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f380a3b5fa0 R15: 00007ffeb2dbadc8
 </TASK>

Allocated by task 13928:
 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:319 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4179 [inline]
 slab_alloc_node mm/slub.c:4228 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4235
 mempool_alloc_noprof+0x1a7/0x510 mm/mempool.c:402
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x509/0xde0 fs/jfs/jfs_metapage.c:758
 dtReadFirst+0xd5/0x930 fs/jfs/jfs_dtree.c:3079
 dtReadNext fs/jfs/jfs_dtree.c:3160 [inline]
 jfs_readdir+0x8ed/0x3ae0 fs/jfs/jfs_dtree.c:2874
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x5af/0x770 fs/readdir.c:108
 __do_sys_getdents fs/readdir.c:326 [inline]
 __se_sys_getdents+0xe4/0x250 fs/readdir.c:312
 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 13928:
 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:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2416 [inline]
 slab_free mm/slub.c:4679 [inline]
 kmem_cache_free+0x18f/0x400 mm/slub.c:4781
 free_metapage fs/jfs/jfs_metapage.c:279 [inline]
 drop_metapage fs/jfs/jfs_metapage.c:316 [inline]
 release_metapage+0x859/0xac0 fs/jfs/jfs_metapage.c:890
 dtReadNext fs/jfs/jfs_dtree.c:3202 [inline]
 jfs_readdir+0xecb/0x3ae0 fs/jfs/jfs_dtree.c:2874
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x5af/0x770 fs/readdir.c:108
 __do_sys_getdents fs/readdir.c:326 [inline]
 __se_sys_getdents+0xe4/0x250 fs/readdir.c:312
 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 ffff88807e49bd90
 which belongs to the cache jfs_mp of size 184
The buggy address is located 48 bytes inside of
 freed 184-byte region [ffff88807e49bd90, ffff88807e49be48)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807e49b5d0 pfn:0x7e49b
anon flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801e7ba780 0000000000000000 0000000000000001
raw: ffff88807e49b5d0 0000000080100009 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 7026, tgid 7021 (syz.5.290), ts 194122643071, free_ts 192843656905
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2486 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2654
 new_slab mm/slub.c:2708 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3890
 __slab_alloc mm/slub.c:3980 [inline]
 __slab_alloc_node mm/slub.c:4055 [inline]
 slab_alloc_node mm/slub.c:4216 [inline]
 kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4235
 mempool_alloc_noprof+0x1a7/0x510 mm/mempool.c:402
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x509/0xde0 fs/jfs/jfs_metapage.c:758
 dbMount+0xeb/0xb80 fs/jfs/jfs_dmap.c:169
 jfs_mount+0x1e7/0x870 fs/jfs/jfs_mount.c:121
 jfs_fill_super+0x6bc/0xd80 fs/jfs/super.c:523
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
 vfs_get_tree+0x92/0x2b0 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 23 tgid 23 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 pagetable_free include/linux/mm.h:2886 [inline]
 pagetable_dtor_free include/linux/mm.h:2984 [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+0xcab/0x1770 kernel/rcu/tree.c:2861
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:464
 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:
 ffff88807e49bc80: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807e49bd00: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc
>ffff88807e49bd80: fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff88807e49be00: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
 ffff88807e49be80: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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