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BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1
Read of size 1 at addr ffff8880117ded6d by task syz.4.379/9194

CPU: 1 UID: 0 PID: 9194 Comm: syz.4.379 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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
 dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1
 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
 dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871
 jfs_symlink+0x715/0xe60 fs/jfs/namei.c:1020
 vfs_symlink+0x143/0x2f0 fs/namei.c:4856
 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4882
 __do_sys_symlink fs/namei.c:4903 [inline]
 __se_sys_symlink fs/namei.c:4901 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4901
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f836418f6c9
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:00007f8364f83038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007f83643e5fa0 RCX: 00007f836418f6c9
RDX: 0000000000000000 RSI: 0000200000000300 RDI: 00002000000002c0
RBP: 00007f8364211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f83643e6038 R14: 00007f83643e5fa0 R15: 00007ffc9a515ea8
 </TASK>

Allocated by task 9194:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 unpoison_slab_object mm/kasan/common.c:339 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4950 [inline]
 slab_alloc_node mm/slub.c:5260 [inline]
 kmem_cache_alloc_lru_noprof+0x36c/0x6e0 mm/slub.c:5279
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 iget_locked+0x135/0x6c0 fs/inode.c:1473
 jfs_iget+0x24/0x470 fs/jfs/inode.c:29
 jfs_lookup+0x1c5/0x380 fs/jfs/namei.c:1469
 __lookup_slow+0x297/0x3d0 fs/namei.c:1855
 lookup_slow+0x53/0x70 fs/namei.c:1872
 walk_component+0x2d2/0x400 fs/namei.c:2190
 lookup_last fs/namei.c:2691 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2715
 filename_lookup+0x212/0x570 fs/namei.c:2744
 user_path_at+0x3a/0x60 fs/namei.c:3254
 __do_sys_chdir fs/open.c:558 [inline]
 __se_sys_chdir+0x91/0x280 fs/open.c:552
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880117de4b8
 which belongs to the cache jfs_ip of size 2216
The buggy address is located 13 bytes to the right of
 allocated 2216-byte region [ffff8880117de4b8, ffff8880117ded60)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x117d8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88805b405801
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801bb64000 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff88805b405801
head: 00fff00000000040 ffff88801bb64000 dead000000000122 0000000000000000
head: 0000000000000000 00000000800d000d 00000000f5000000 ffff88805b405801
head: 00fff00000000003 ffffea000045f601 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6011, tgid 6010 (syz.3.19), ts 102482548662, free_ts 101672746180
 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+0x2365/0x2440 mm/page_alloc.c:3920
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486
 alloc_slab_page mm/slub.c:3077 [inline]
 allocate_slab+0x96/0x350 mm/slub.c:3250
 new_slab mm/slub.c:3304 [inline]
 ___slab_alloc+0xf56/0x1990 mm/slub.c:4653
 __slab_alloc+0x65/0x100 mm/slub.c:4776
 __slab_alloc_node mm/slub.c:4852 [inline]
 slab_alloc_node mm/slub.c:5248 [inline]
 kmem_cache_alloc_lru_noprof+0x3fe/0x6e0 mm/slub.c:5279
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 new_inode+0x22/0x170 fs/inode.c:1175
 jfs_fill_super+0x569/0xd80 fs/jfs/super.c:511
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1697
 vfs_get_tree+0x92/0x2b0 fs/super.c:1757
 fc_mount fs/namespace.c:1209 [inline]
 do_new_mount_fc fs/namespace.c:3652 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3728
 do_mount fs/namespace.c:4051 [inline]
 __do_sys_mount fs/namespace.c:4240 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4217
page last free pid 5845 tgid 5845 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2948
 discard_slab mm/slub.c:3348 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3888
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3963
 __slab_free+0x288/0x2a0 mm/slub.c:5949
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4950 [inline]
 slab_alloc_node mm/slub.c:5260 [inline]
 kmem_cache_alloc_noprof+0x37d/0x700 mm/slub.c:5267
 getname_flags+0xb8/0x540 fs/namei.c:146
 getname include/linux/fs.h:2522 [inline]
 getname_maybe_null include/linux/fs.h:2529 [inline]
 vfs_fstatat+0x43/0x170 fs/stat.c:370
 __do_sys_newfstatat fs/stat.c:542 [inline]
 __se_sys_newfstatat fs/stat.c:536 [inline]
 __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8880117dec00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880117dec80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880117ded00: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
                                                          ^
 ffff8880117ded80: fc fc fc fc fc fc fc fc fc fc fc fc fa fb fb fb
 ffff8880117dee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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