==================================================================
BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1
Read of size 1 at addr ffff88805c9eb065 by task syz.4.144/6879

CPU: 1 UID: 0 PID: 6879 Comm: syz.4.144 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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_mkdir+0x6ec/0xa70 fs/jfs/namei.c:270
 vfs_mkdir+0x306/0x510 fs/namei.c:4453
 do_mkdirat+0x247/0x590 fs/namei.c:4486
 __do_sys_mkdirat fs/namei.c:4503 [inline]
 __se_sys_mkdirat fs/namei.c:4501 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
 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: 0033:0x7ff77b34d617
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007ff7795b5e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007ff7795b5ef0 RCX: 00007ff77b34d617
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c
RBP: 00002000000002c0 R08: 00002000000007c0 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000246 R12: 00002000000000c0
R13: 00007ff7795b5eb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 6879:
 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:342 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4955 [inline]
 slab_alloc_node mm/slub.c:5265 [inline]
 kmem_cache_alloc_lru_noprof+0x188/0x6b0 mm/slub.c:5284
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 iget_locked+0x106/0x580 fs/inode.c:1445
 jfs_iget+0x24/0x470 fs/jfs/inode.c:29
 jfs_lookup+0x1c5/0x380 fs/jfs/namei.c:1469
 __lookup_slow+0x29d/0x3d0 fs/namei.c:1816
 lookup_slow+0x53/0x70 fs/namei.c:1833
 walk_component+0x2d2/0x400 fs/namei.c:2151
 lookup_last fs/namei.c:2652 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2676
 filename_lookup+0x212/0x570 fs/namei.c:2705
 user_path_at+0x3a/0x60 fs/namei.c:3215
 __do_sys_chdir fs/open.c:561 [inline]
 __se_sys_chdir+0x91/0x280 fs/open.c:555
 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 ffff88805c9ea700
 which belongs to the cache jfs_ip of size 2368
The buggy address is located 37 bytes to the right of
 allocated 2368-byte region [ffff88805c9ea700, ffff88805c9eb040)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c9e8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88802d4ea001
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff8881404f6780 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff88802d4ea001
head: 0080000000000040 ffff8881404f6780 dead000000000122 0000000000000000
head: 0000000000000000 00000000800d000d 00000000f5000000 ffff88802d4ea001
head: 0080000000000003 ffffea0001727a01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 6042, tgid 6040 (syz.1.20), ts 111757233576, free_ts 110460026920
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3039 [inline]
 allocate_slab+0x96/0x3a0 mm/slub.c:3212
 new_slab mm/slub.c:3266 [inline]
 ___slab_alloc+0xb12/0x13f0 mm/slub.c:4636
 __slab_alloc+0xc6/0x1f0 mm/slub.c:4755
 __slab_alloc_node mm/slub.c:4831 [inline]
 slab_alloc_node mm/slub.c:5253 [inline]
 kmem_cache_alloc_lru_noprof+0xf0/0x6b0 mm/slub.c:5284
 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:1145
 ialloc+0x4c/0x8f0 fs/jfs/jfs_inode.c:48
 jfs_symlink+0x1c4/0xe60 fs/jfs/namei.c:917
 vfs_symlink+0x143/0x2f0 fs/namei.c:4817
 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4843
 __do_sys_symlink fs/namei.c:4864 [inline]
 __se_sys_symlink fs/namei.c:4862 [inline]
 __x64_sys_symlink+0x7a/0x90 fs/namei.c:4862
page last free pid 5937 tgid 5937 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xfb6/0x1140 mm/page_alloc.c:2906
 __slab_free+0x2c6/0x370 mm/slub.c:5947
 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:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4955 [inline]
 slab_alloc_node mm/slub.c:5265 [inline]
 kmem_cache_alloc_noprof+0x181/0x6b0 mm/slub.c:5272
 anon_vma_chain_alloc mm/rmap.c:141 [inline]
 __anon_vma_prepare+0xcb/0x4a0 mm/rmap.c:194
 __vmf_anon_prepare mm/memory.c:3633 [inline]
 vmf_anon_prepare mm/internal.h:432 [inline]
 do_anonymous_page mm/memory.c:5178 [inline]
 do_pte_missing mm/memory.c:4359 [inline]
 handle_pte_fault mm/memory.c:6177 [inline]
 __handle_mm_fault mm/memory.c:6318 [inline]
 handle_mm_fault+0x2a86/0x3400 mm/memory.c:6487
 do_user_addr_fault+0x764/0x1380 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618

Memory state around the buggy address:
 ffff88805c9eaf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805c9eaf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805c9eb000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                                       ^
 ffff88805c9eb080: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
 ffff88805c9eb100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================