bn = 72c, index = 96
bn = 0, index = 0
bn = 72c, index = 96
bn = 0, index = 0
bn = 72c, index = 96
bn = 0, index = 0
bn = 0, index = 0
==================================================================
BUG: KASAN: slab-use-after-free in drop_metapage fs/jfs/jfs_metapage.c:311 [inline]
BUG: KASAN: slab-use-after-free in release_metapage+0x753/0xab0 fs/jfs/jfs_metapage.c:892
Read of size 8 at addr ffff8880629229e8 by task syz.7.124/6970

CPU: 1 UID: 0 PID: 6970 Comm: syz.7.124 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 drop_metapage fs/jfs/jfs_metapage.c:311 [inline]
 release_metapage+0x753/0xab0 fs/jfs/jfs_metapage.c:892
 dtSearch+0x1c4e/0x21b0 fs/jfs/jfs_dtree.c:793
 jfs_symlink+0x857/0xfd0 fs/jfs/namei.c:1017
 vfs_symlink+0x29a/0x2d0 fs/namei.c:5523
 do_symlinkat+0x1f1/0x3c0 fs/namei.c:5550
 __do_sys_symlinkat fs/namei.c:5571 [inline]
 __se_sys_symlinkat fs/namei.c:5568 [inline]
 __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:5568
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6a480cacb9
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:00007f6a46326028 EFLAGS: 00000246 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 00007f6a48345fa0 RCX: 00007f6a480cacb9
RDX: 00002000000007c0 RSI: 0000000000000005 RDI: 0000200000000440
RBP: 00007f6a48138bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6a48346038 R14: 00007f6a48345fa0 R15: 00007fff50b5db48
 </TASK>

Allocated by task 6970:
 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:4953 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 kmem_cache_alloc_noprof+0x188/0x6a0 mm/slub.c:5270
 mempool_alloc_noprof+0x1d4/0x300 mm/mempool.c:567
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x50c/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+0xedd/0x5de0 fs/jfs/jfs_dtree.c:871
 jfs_create+0x75b/0xb10 fs/jfs/namei.c:137
 lookup_open fs/namei.c:4449 [inline]
 open_last_lookups fs/namei.c:4549 [inline]
 path_openat+0x1902/0x3e70 fs/namei.c:4793
 do_filp_open+0x22d/0x490 fs/namei.c:4823
 do_sys_openat2+0x12f/0x220 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6995:
 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:2540 [inline]
 slab_free mm/slub.c:6674 [inline]
 kmem_cache_free+0x18d/0x8c0 mm/slub.c:6785
 mempool_free+0xf5/0x140 mm/mempool.c:712
 free_metapage fs/jfs/jfs_metapage.c:279 [inline]
 metapage_release_folio+0x478/0x5b0 fs/jfs/jfs_metapage.c:636
 folio_invalidate mm/truncate.c:140 [inline]
 truncate_cleanup_folio+0x2d8/0x430 mm/truncate.c:160
 truncate_inode_pages_range+0x2d1/0xe30 mm/truncate.c:404
 jfs_reconfigure+0x5ac/0xa00 fs/jfs/super.c:406
 reconfigure_super+0x227/0x8a0 fs/super.c:1077
 do_remount fs/namespace.c:3264 [inline]
 path_mount+0xd3e/0x1000 fs/namespace.c:4014
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880629229c0
 which belongs to the cache jfs_mp of size 248
The buggy address is located 40 bytes inside of
 freed 248-byte region [ffff8880629229c0, ffff888062922ab8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x62922
ksm flags: 0x80000000000000(node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000000 ffff8881452dadc0 ffffea0000e6ae00 0000000000000003
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 6281, tgid 6280 (syz.0.57), ts 122349960825, free_ts 122330459332
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884
 prep_new_page mm/page_alloc.c:1892 [inline]
 get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3945
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5240
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486
 alloc_slab_page mm/slub.c:3075 [inline]
 allocate_slab+0x86/0x3a0 mm/slub.c:3248
 new_slab mm/slub.c:3302 [inline]
 ___slab_alloc+0xaf8/0x13d0 mm/slub.c:4656
 __slab_alloc+0xc5/0x1f0 mm/slub.c:4779
 __slab_alloc_node mm/slub.c:4855 [inline]
 slab_alloc_node mm/slub.c:5251 [inline]
 kmem_cache_alloc_noprof+0x100/0x6a0 mm/slub.c:5270
 mempool_alloc_noprof+0x1d4/0x300 mm/mempool.c:567
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x50c/0xde0 fs/jfs/jfs_metapage.c:760
 diWrite+0x401/0x1f40 fs/jfs/jfs_imap.c:639
 txCommit+0x869/0x5410 fs/jfs/jfs_txnmgr.c:1256
 jfs_create+0x8f4/0xb10 fs/jfs/namei.c:156
 lookup_open fs/namei.c:4449 [inline]
 open_last_lookups fs/namei.c:4549 [inline]
 path_openat+0x1902/0x3e70 fs/namei.c:4793
 do_filp_open+0x22d/0x490 fs/namei.c:4823
 do_sys_openat2+0x12f/0x220 fs/open.c:1430
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:1433 [inline]
 __free_frozen_pages+0xfc1/0x1130 mm/page_alloc.c:2973
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core kernel/rcu/tree.c:2857 [inline]
 rcu_cpu_kthread+0xbba/0x1b10 kernel/rcu/tree.c:2945
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x726/0x8b0 kernel/kthread.c:463
 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Memory state around the buggy address:
 ffff888062922880: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888062922900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888062922980: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
                                                          ^
 ffff888062922a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888062922a80: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc 00
==================================================================