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BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x1248/0x37c0 fs/jfs/jfs_dtree.c:-1
Read of size 1 at addr ffff88805e75ba25 by task syz.2.3/5915

CPU: 0 UID: 0 PID: 5915 Comm: syz.2.3 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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
 dtSplitPage+0x1248/0x37c0 fs/jfs/jfs_dtree.c:-1
 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
 dtInsert+0x10a4/0x5f10 fs/jfs/jfs_dtree.c:871
 jfs_mkdir+0x783/0xb00 fs/jfs/namei.c:271
 vfs_mkdir+0x40b/0x630 fs/namei.c:5233
 filename_mkdirat+0x289/0x520 fs/namei.c:5266
 __do_sys_mkdir fs/namei.c:5293 [inline]
 __se_sys_mkdir+0x34/0x150 fs/namei.c:5290
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f60319ec799
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:00007f602fc25028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f6031c66090 RCX: 00007f60319ec799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000300
RBP: 00007f6031a82bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6031c66128 R14: 00007f6031c66090 R15: 00007fff56fc6218
 </TASK>

Allocated by task 5912:
 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:4515 [inline]
 slab_alloc_node mm/slub.c:4844 [inline]
 kmem_cache_alloc_lru_noprof+0x33c/0x680 mm/slub.c:4863
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:347
 iget_locked+0x131/0x6a0 fs/inode.c:1480
 jfs_iget+0x24/0x470 fs/jfs/inode.c:29
 jfs_lookup+0x220/0x420 fs/jfs/namei.c:1472
 __lookup_slow+0x2d2/0x440 fs/namei.c:1916
 lookup_slow+0x53/0x70 fs/namei.c:1933
 walk_component fs/namei.c:2279 [inline]
 lookup_last fs/namei.c:2780 [inline]
 path_lookupat+0x3f5/0x8c0 fs/namei.c:2804
 filename_lookup+0x256/0x5d0 fs/namei.c:2833
 __do_sys_chdir fs/open.c:559 [inline]
 __se_sys_chdir+0xa8/0x2a0 fs/open.c:552
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805e75b0c0
 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 [ffff88805e75b0c0, ffff88805e75ba00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805e75eb40 pfn:0x5e758
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88805e75fec1
flags: 0x80000000000240(workingset|head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000240 ffff88814043cc80 ffff88801e721c88 ffff88801e721c88
raw: ffff88805e75eb40 00000008000d000b 00000000f5000000 ffff88805e75fec1
head: 0080000000000240 ffff88814043cc80 ffff88801e721c88 ffff88801e721c88
head: ffff88805e75eb40 00000008000d000b 00000000f5000000 ffff88805e75fec1
head: 0080000000000003 ffffea000179d601 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 5912, tgid 5911 (syz.2.3), ts 83807904368, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3269 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3458
 new_slab mm/slub.c:3516 [inline]
 refill_objects+0x334/0x3c0 mm/slub.c:7153
 refill_sheaf+0x29/0x50 mm/slub.c:2818
 alloc_full_sheaf mm/slub.c:2839 [inline]
 __pcs_replace_empty_main+0x3ab/0x5f0 mm/slub.c:4602
 alloc_from_pcs mm/slub.c:4695 [inline]
 slab_alloc_node mm/slub.c:4829 [inline]
 kmem_cache_alloc_lru_noprof+0x433/0x680 mm/slub.c:4863
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:347
 new_inode+0x22/0x170 fs/inode.c:1185
 diReadSpecial+0x52/0x710 fs/jfs/jfs_imap.c:426
 jfs_mount+0x73/0x870 fs/jfs/jfs_mount.c:87
 jfs_fill_super+0x6bc/0xd80 fs/jfs/super.c:523
 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88805e75b900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805e75b980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805e75ba00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff88805e75ba80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805e75bb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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