loop6: detected capacity change from 0 to 32768
 ... Log Wrap ... Log Wrap ... Log Wrap ...
==================================================================
BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x1248/0x37c0 fs/jfs/jfs_dtree.c:-1
Read of size 1 at addr ffff88805fb1f4a5 by task syz.6.2323/21459

CPU: 1 UID: 0 PID: 21459 Comm: syz.6.2323 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
 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:270
 vfs_mkdir+0x75d/0x870 fs/namei.c:5139
 do_mkdirat+0x281/0x4c0 fs/namei.c:5173
 __do_sys_mkdirat fs/namei.c:5195 [inline]
 __se_sys_mkdirat fs/namei.c:5193 [inline]
 __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5193
 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: 0033:0x7fed5c2b9d97
Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 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:00007fed5a515e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fed5a515ee0 RCX: 00007fed5c2b9d97
RDX: 00000000000001ff RSI: 0000200000000040 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000040
R13: 00007fed5a515ea0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 21459:
 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_lru_noprof+0x18e/0x6a0 mm/slub.c:5282
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 iget_locked+0x131/0x6a0 fs/inode.c:1470
 jfs_iget+0x24/0x470 fs/jfs/inode.c:29
 jfs_lookup+0x220/0x420 fs/jfs/namei.c:1469
 __lookup_slow+0x2d2/0x440 fs/namei.c:1866
 lookup_slow+0x53/0x70 fs/namei.c:1883
 walk_component fs/namei.c:2229 [inline]
 lookup_last fs/namei.c:2730 [inline]
 path_lookupat+0x3f5/0x8c0 fs/namei.c:2754
 filename_lookup+0x256/0x5d0 fs/namei.c:2783
 user_path_at+0x3a/0x60 fs/namei.c:3576
 __do_sys_chdir fs/open.c:558 [inline]
 __se_sys_chdir+0x98/0x280 fs/open.c:552
 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 ffff88805fb1eb40
 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 [ffff88805fb1eb40, ffff88805fb1f480)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805fb1d7c0 pfn:0x5fb18
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88805e950001
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88801c3d9280 ffffea0000fcb800 0000000000000004
raw: ffff88805fb1d7c0 00000000800d000a 00000000f5000000 ffff88805e950001
head: 0080000000000040 ffff88801c3d9280 ffffea0000fcb800 0000000000000004
head: ffff88805fb1d7c0 00000000800d000a 00000000f5000000 ffff88805e950001
head: 0080000000000003 ffffea00017ec601 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 8953, tgid 8952 (syz.9.604), ts 303820603968, free_ts 303524650756
 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_lru_noprof+0x103/0x6a0 mm/slub.c:5282
 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
 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:1691
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
page last free pid 8952 tgid 8952 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0xfd0/0x1160 mm/page_alloc.c:2973
 __slab_free+0x2e6/0x330 mm/slub.c:6008
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 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
 getname_flags+0xb7/0x540 fs/namei.c:146
 user_path_at+0x24/0x60 fs/namei.c:3575
 __do_sys_chdir fs/open.c:558 [inline]
 __se_sys_chdir+0x98/0x280 fs/open.c:552
 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

Memory state around the buggy address:
 ffff88805fb1f380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805fb1f400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805fb1f480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                               ^
 ffff88805fb1f500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805fb1f580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================