==================================================================
BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x2f18/0x3740 fs/jfs/jfs_dtree.c:1522
Read of size 1 at addr ffff88805f5fb67d by task syz.5.1388/12558

CPU: 1 UID: 0 PID: 12558 Comm: syz.5.1388 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 dtSplitPage+0x2f18/0x3740 fs/jfs/jfs_dtree.c:1522
 dtSplitUp+0x7ec/0x5920 fs/jfs/jfs_dtree.c:1092
 dtInsert+0x8dd/0xb40 fs/jfs/jfs_dtree.c:871
 jfs_mkdir+0x641/0xb50 fs/jfs/namei.c:271
 vfs_mkdir+0x361/0x850 fs/namei.c:5233
 filename_mkdirat+0x48b/0x5e0 fs/namei.c:5266
 __do_sys_mkdirat fs/namei.c:5287 [inline]
 __se_sys_mkdirat fs/namei.c:5284 [inline]
 __x64_sys_mkdirat+0x89/0xc0 fs/namei.c:5284
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e6739c799
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:00007f6e68233028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f6e67616180 RCX: 00007f6e6739c799
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007f6e67432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6e67616218 R14: 00007f6e67616180 R15: 00007ffc63f869f8
 </TASK>

Allocated by task 12539:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_lru_noprof+0x246/0x6e0 mm/slub.c:4885
 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105
 alloc_inode+0x68/0x250 fs/inode.c:347
 iget_locked+0x1d9/0x6d0 fs/inode.c:1480
 jfs_iget+0x20/0x530 fs/jfs/inode.c:29
 jfs_lookup+0x285/0x330 fs/jfs/namei.c:1472
 __lookup_slow+0x251/0x460 fs/namei.c:1916
 lookup_slow+0x50/0x70 fs/namei.c:1933
 walk_component fs/namei.c:2279 [inline]
 lookup_last fs/namei.c:2780 [inline]
 path_lookupat+0x5e8/0xc40 fs/namei.c:2804
 filename_lookup+0x202/0x590 fs/namei.c:2833
 __do_sys_chdir fs/open.c:559 [inline]
 __se_sys_chdir fs/open.c:552 [inline]
 __x64_sys_chdir+0xc8/0x280 fs/open.c:552
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805f5fadc8
 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 [ffff88805f5fadc8, ffff88805f5fb670)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805f5fa4a0 pfn:0x5f5f8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88805f5ff709
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff888140ad8500 ffff8880206d8b88 ffffea00017dc610
raw: ffff88805f5fa4a0 00000008000d0008 00000000f5000000 ffff88805f5ff709
head: 00fff00000000240 ffff888140ad8500 ffff8880206d8b88 ffffea00017dc610
head: ffff88805f5fa4a0 00000008000d0008 00000000f5000000 ffff88805f5ff709
head: 00fff00000000003 ffffea00017d7e01 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 11823, tgid 11822 (syz.1.1256), ts 1008242517219, free_ts 945685181931
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3292 [inline]
 allocate_slab mm/slub.c:3481 [inline]
 new_slab+0xa6/0x6b0 mm/slub.c:3539
 refill_objects+0x26b/0x400 mm/slub.c:7175
 refill_sheaf mm/slub.c:2812 [inline]
 alloc_full_sheaf mm/slub.c:2834 [inline]
 __pcs_replace_empty_main+0x43f/0x660 mm/slub.c:4626
 alloc_from_pcs mm/slub.c:4717 [inline]
 slab_alloc_node mm/slub.c:4851 [inline]
 kmem_cache_alloc_lru_noprof+0x485/0x6e0 mm/slub.c:4885
 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105
 alloc_inode+0x68/0x250 fs/inode.c:347
 new_inode+0x22/0x1c0 fs/inode.c:1185
 jfs_fill_super+0x6a8/0xf50 fs/jfs/super.c:511
 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
 vfs_get_tree+0x92/0x320 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3763 [inline]
 do_new_mount fs/namespace.c:3839 [inline]
 path_mount+0x7d0/0x23d0 fs/namespace.c:4159
 do_mount fs/namespace.c:4172 [inline]
 __do_sys_mount fs/namespace.c:4361 [inline]
 __se_sys_mount fs/namespace.c:4338 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4338
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
page last free pid 11232 tgid 11232 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4873
 alloc_filename fs/namei.c:142 [inline]
 do_getname+0x35/0x390 fs/namei.c:182
 getname include/linux/fs.h:2512 [inline]
 class_filename_constructor include/linux/fs.h:2539 [inline]
 do_sys_openat2+0xc5/0x1e0 fs/open.c:1365
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805f5fb500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805f5fb580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88805f5fb600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
                                                                ^
 ffff88805f5fb680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc 00 00
 ffff88805f5fb700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
==================================================================
BUG: KASAN: slab-out-of-bounds in dtInsertEntry.isra.0+0x148c/0x1630 fs/jfs/jfs_dtree.c:3765
Read of size 4 at addr ffff88805f5fb694 by task syz.5.1388/12558

CPU: 0 UID: 0 PID: 12558 Comm: syz.5.1388 Tainted: G    B               syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 dtInsertEntry.isra.0+0x148c/0x1630 fs/jfs/jfs_dtree.c:3765
 dtSplitPage+0x231a/0x3740 fs/jfs/jfs_dtree.c:1596
 dtSplitUp+0x7ec/0x5920 fs/jfs/jfs_dtree.c:1092
 dtInsert+0x8dd/0xb40 fs/jfs/jfs_dtree.c:871
 jfs_mkdir+0x641/0xb50 fs/jfs/namei.c:271
 vfs_mkdir+0x361/0x850 fs/namei.c:5233
 filename_mkdirat+0x48b/0x5e0 fs/namei.c:5266
 __do_sys_mkdirat fs/namei.c:5287 [inline]
 __se_sys_mkdirat fs/namei.c:5284 [inline]
 __x64_sys_mkdirat+0x89/0xc0 fs/namei.c:5284
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e6739c799
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:00007f6e68233028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f6e67616180 RCX: 00007f6e6739c799
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007f6e67432c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6e67616218 R14: 00007f6e67616180 R15: 00007ffc63f869f8
 </TASK>

Allocated by task 12539:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_lru_noprof+0x246/0x6e0 mm/slub.c:4885
 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105
 alloc_inode+0x68/0x250 fs/inode.c:347
 iget_locked+0x1d9/0x6d0 fs/inode.c:1480
 jfs_iget+0x20/0x530 fs/jfs/inode.c:29
 jfs_lookup+0x285/0x330 fs/jfs/namei.c:1472
 __lookup_slow+0x251/0x460 fs/namei.c:1916
 lookup_slow+0x50/0x70 fs/namei.c:1933
 walk_component fs/namei.c:2279 [inline]
 lookup_last fs/namei.c:2780 [inline]
 path_lookupat+0x5e8/0xc40 fs/namei.c:2804
 filename_lookup+0x202/0x590 fs/namei.c:2833
 __do_sys_chdir fs/open.c:559 [inline]
 __se_sys_chdir fs/open.c:552 [inline]
 __x64_sys_chdir+0xc8/0x280 fs/open.c:552
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805f5fadc8
 which belongs to the cache jfs_ip of size 2216
The buggy address is located 36 bytes to the right of
 allocated 2216-byte region [ffff88805f5fadc8, ffff88805f5fb670)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805f5fa4a0 pfn:0x5f5f8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88805f5ff709
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff888140ad8500 ffff8880206d8b88 ffffea00017dc610
raw: ffff88805f5fa4a0 00000008000d0008 00000000f5000000 ffff88805f5ff709
head: 00fff00000000240 ffff888140ad8500 ffff8880206d8b88 ffffea00017dc610
head: ffff88805f5fa4a0 00000008000d0008 00000000f5000000 ffff88805f5ff709
head: 00fff00000000003 ffffea00017d7e01 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 11823, tgid 11822 (syz.1.1256), ts 1008242517219, free_ts 945685181931
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3292 [inline]
 allocate_slab mm/slub.c:3481 [inline]
 new_slab+0xa6/0x6b0 mm/slub.c:3539
 refill_objects+0x26b/0x400 mm/slub.c:7175
 refill_sheaf mm/slub.c:2812 [inline]
 alloc_full_sheaf mm/slub.c:2834 [inline]
 __pcs_replace_empty_main+0x43f/0x660 mm/slub.c:4626
 alloc_from_pcs mm/slub.c:4717 [inline]
 slab_alloc_node mm/slub.c:4851 [inline]
 kmem_cache_alloc_lru_noprof+0x485/0x6e0 mm/slub.c:4885
 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105
 alloc_inode+0x68/0x250 fs/inode.c:347
 new_inode+0x22/0x1c0 fs/inode.c:1185
 jfs_fill_super+0x6a8/0xf50 fs/jfs/super.c:511
 get_tree_bdev_flags+0x38c/0x620 fs/super.c:1694
 vfs_get_tree+0x92/0x320 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3763 [inline]
 do_new_mount fs/namespace.c:3839 [inline]
 path_mount+0x7d0/0x23d0 fs/namespace.c:4159
 do_mount fs/namespace.c:4172 [inline]
 __do_sys_mount fs/namespace.c:4361 [inline]
 __se_sys_mount fs/namespace.c:4338 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4338
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
page last free pid 11232 tgid 11232 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4873
 alloc_filename fs/namei.c:142 [inline]
 do_getname+0x35/0x390 fs/namei.c:182
 getname include/linux/fs.h:2512 [inline]
 class_filename_constructor include/linux/fs.h:2539 [inline]
 do_sys_openat2+0xc5/0x1e0 fs/open.c:1365
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x12d/0x210 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805f5fb580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805f5fb600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
>ffff88805f5fb680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc 00 00
                         ^
 ffff88805f5fb700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88805f5fb780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
find_entry called with index >= next_index
read_mapping_page failed!
ERROR: (device loop5): txAbort: