==================================================================
BUG: KASAN: slab-out-of-bounds in dtCompare fs/jfs/jfs_dtree.c:3333 [inline]
BUG: KASAN: slab-out-of-bounds in dtSearch+0x12d4/0x1b18 fs/jfs/jfs_dtree.c:650
Read of size 1 at addr ffff0000f68e4078 by task syz.1.2/4426

CPU: 1 PID: 4426 Comm: syz.1.2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call trace:
 dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load1_noabort+0x2c/0x38 mm/kasan/report_generic.c:348
 dtCompare fs/jfs/jfs_dtree.c:3333 [inline]
 dtSearch+0x12d4/0x1b18 fs/jfs/jfs_dtree.c:650
 jfs_lookup+0x164/0x378 fs/jfs/namei.c:1461
 lookup_one_qstr_excl+0x108/0x230 fs/namei.c:1613
 filename_create+0x1d0/0x3a8 fs/namei.c:3885
 do_linkat+0x16c/0x4e4 fs/namei.c:4662
 __do_sys_linkat fs/namei.c:4706 [inline]
 __se_sys_linkat fs/namei.c:4703 [inline]
 __arm64_sys_linkat+0xe4/0x100 fs/namei.c:4703
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Allocated by task 4418:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x74/0x430 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc_lru+0x1a4/0x280 mm/slub.c:3390
 alloc_inode_sb include/linux/fs.h:3245 [inline]
 jfs_alloc_inode+0x2c/0x68 fs/jfs/super.c:105
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x178/0x7c4 fs/inode.c:1373
 jfs_iget+0x30/0x3e4 fs/jfs/inode.c:29
 jfs_lookup+0x1c0/0x378 fs/jfs/namei.c:1469
 lookup_open fs/namei.c:3468 [inline]
 open_last_lookups fs/namei.c:3558 [inline]
 path_openat+0xc98/0x26bc fs/namei.c:3788
 do_filp_open+0x194/0x384 fs/namei.c:3818
 do_sys_openat2+0x134/0x3f4 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __arm64_sys_openat+0x118/0x14c fs/open.c:1347
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000f68e3780
 which belongs to the cache jfs_ip of size 2240
The buggy address is located 56 bytes to the right of
 2240-byte region [ffff0000f68e3780, ffff0000f68e4040)

The buggy address belongs to the physical page:
page:00000000f2dabb13 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1368e0
head:00000000f2dabb13 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff0000cf3c0f01
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 0000000000000000 dead000000000122 ffff0000c4320d80
raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff0000cf3c0f01
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000f68e3f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000f68e3f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000f68e4000: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                                                ^
 ffff0000f68e4080: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff0000f68e4100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
ERROR: (device loop1): dtSearch: stack overrun!

ERROR: (device loop1): remounting filesystem as read-only
btstack dump:
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
bn = 0, index = 0
jfs_lookup: dtSearch returned -5