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BUG: KASAN: slab-use-after-free in jfs_readdir+0x10a8/0x33f0 fs/jfs/jfs_dtree.c:2878
Read of size 8 at addr ffff888040376b28 by task syz.8.263/8380

CPU: 1 UID: 0 PID: 8380 Comm: syz.8.263 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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+0x10a8/0x33f0 fs/jfs/jfs_dtree.c:2878
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:67
 iterate_dir+0x2f1/0x4e0 fs/readdir.c:110
 __do_sys_getdents fs/readdir.c:319 [inline]
 __se_sys_getdents+0xf1/0x270 fs/readdir.c:304
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55e955e159
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:00007f55e7795028 EFLAGS: 00000246 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007f55e97e6090 RCX: 00007f55e955e159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f55e95f506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55e97e6128 R14: 00007f55e97e6090 R15: 00007fffd6cf2a68
 </TASK>

Allocated by task 8380:
 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:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 kmem_cache_alloc_noprof+0x360/0x690 mm/slub.c:5010
 mempool_alloc_noprof+0x1c5/0x300 mm/mempool.c:572
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x4ed/0xdf0 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+0x8bb/0x33f0 fs/jfs/jfs_dtree.c:2871
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:67
 iterate_dir+0x2f1/0x4e0 fs/readdir.c:110
 __do_sys_getdents fs/readdir.c:319 [inline]
 __se_sys_getdents+0xf1/0x270 fs/readdir.c:304
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 8380:
 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:2748 [inline]
 slab_free mm/slub.c:6508 [inline]
 kmem_cache_free+0x187/0x6d0 mm/slub.c:6635
 mempool_free+0xf5/0x140 mm/mempool.c:717
 free_metapage fs/jfs/jfs_metapage.c:280 [inline]
 drop_metapage fs/jfs/jfs_metapage.c:317 [inline]
 release_metapage+0x7eb/0xa50 fs/jfs/jfs_metapage.c:893
 dtReadNext fs/jfs/jfs_dtree.c:3199 [inline]
 jfs_readdir+0xe35/0x33f0 fs/jfs/jfs_dtree.c:2871
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:67
 iterate_dir+0x2f1/0x4e0 fs/readdir.c:110
 __do_sys_getdents fs/readdir.c:319 [inline]
 __se_sys_getdents+0xf1/0x270 fs/readdir.c:304
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888040376af8
 which belongs to the cache jfs_mp of size 248
The buggy address is located 48 bytes inside of
 freed 248-byte region [ffff888040376af8, ffff888040376bf0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888040376d68 pfn:0x40376
flags: 0x80000000000200(workingset|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000200 ffff88801ebcc280 ffffea00017d8ed0 ffffea0000c9e6d0
raw: ffff888040376d68 00000002000d0008 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 6482, tgid 6481 (syz.5.65), ts 161878136213
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x2591/0x2600 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x230/0x5c0 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab+0x7d/0x620 mm/slub.c:3462
 new_slab mm/slub.c:3513 [inline]
 refill_objects+0x2d8/0x350 mm/slub.c:7417
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x339/0x690 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 kmem_cache_alloc_noprof+0x45d/0x690 mm/slub.c:5010
 mempool_alloc_noprof+0x1c5/0x300 mm/mempool.c:572
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x4ed/0xdf0 fs/jfs/jfs_metapage.c:761
 diIAGRead fs/jfs/jfs_imap.c:2672 [inline]
 diRead+0x211/0xbc0 fs/jfs/jfs_imap.c:316
 jfs_iget+0x89/0x470 fs/jfs/inode.c:35
 jfs_fill_super+0x8ff/0xda0 fs/jfs/super.c:548
 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1873
 vfs_get_tree+0x92/0x2a0 fs/super.c:1933
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3772 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3848
 do_mount fs/namespace.c:4181 [inline]
 __do_sys_mount fs/namespace.c:4397 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4374
page last free pid 28 tgid 28 ts 161865221921 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0xf8e/0x1070 mm/page_alloc.c:2962
 rcu_do_batch kernel/rcu/tree.c:2650 [inline]
 rcu_core kernel/rcu/tree.c:2919 [inline]
 rcu_cpu_kthread+0xb2c/0x1740 kernel/rcu/tree.c:3007
 smpboot_thread_fn+0x565/0xa70 kernel/smpboot.c:160
 kthread+0x38b/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:
 ffff888040376a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888040376a80: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa
>ffff888040376b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888040376b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff888040376c00: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb
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