ERROR: (device loop5): dtReadFirst: stbl[0] out of bound
ERROR: (device loop5): remounting filesystem as read-only
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:784:21
index -1 is out of range for type 'struct dtslot[128]'
CPU: 1 UID: 0 PID: 7040 Comm: syz.5.55 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 ubsan_epilogue+0x14/0x48 lib/ubsan.c:233
 __ubsan_handle_out_of_bounds+0xd0/0xfc lib/ubsan.c:455
 dtSearch+0x1664/0x1d00 fs/jfs/jfs_dtree.c:784
 jfs_lookup+0x13c/0x32c fs/jfs/namei.c:1461
 __lookup_slow+0x254/0x378 fs/namei.c:1858
 lookup_slow+0x5c/0x80 fs/namei.c:1875
 walk_component fs/namei.c:2221 [inline]
 lookup_last fs/namei.c:2722 [inline]
 path_lookupat+0x338/0x780 fs/namei.c:2746
 filename_lookup+0x1ac/0x454 fs/namei.c:2775
 kern_path+0x48/0x6c fs/namei.c:2987
 unix_find_bsd net/unix/af_unix.c:1215 [inline]
 unix_find_other+0x150/0x924 net/unix/af_unix.c:1277
 unix_dgram_sendmsg+0x5d4/0x132c net/unix/af_unix.c:2151
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x490/0x7c4 net/socket.c:2592
 ___sys_sendmsg+0x204/0x278 net/socket.c:2646
 __sys_sendmmsg+0x1f4/0x548 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2762 [inline]
 __se_sys_sendmmsg net/socket.c:2759 [inline]
 __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2759
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
---[ end trace ]---
==================================================================
BUG: KASAN: use-after-free in addressPXD fs/jfs/jfs_types.h:80 [inline]
BUG: KASAN: use-after-free in dtSearch+0x1680/0x1d00 fs/jfs/jfs_dtree.c:785
Read of size 4 at addr ffff0000da8d0fe0 by task syz.5.55/7040

CPU: 1 UID: 0 PID: 7040 Comm: syz.5.55 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xa8/0x238 mm/kasan/report.c:378
 print_report+0x68/0x84 mm/kasan/report.c:482
 kasan_report+0xb0/0x110 mm/kasan/report.c:595
 __asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380
 addressPXD fs/jfs/jfs_types.h:80 [inline]
 dtSearch+0x1680/0x1d00 fs/jfs/jfs_dtree.c:785
 jfs_lookup+0x13c/0x32c fs/jfs/namei.c:1461
 __lookup_slow+0x254/0x378 fs/namei.c:1858
 lookup_slow+0x5c/0x80 fs/namei.c:1875
 walk_component fs/namei.c:2221 [inline]
 lookup_last fs/namei.c:2722 [inline]
 path_lookupat+0x338/0x780 fs/namei.c:2746
 filename_lookup+0x1ac/0x454 fs/namei.c:2775
 kern_path+0x48/0x6c fs/namei.c:2987
 unix_find_bsd net/unix/af_unix.c:1215 [inline]
 unix_find_other+0x150/0x924 net/unix/af_unix.c:1277
 unix_dgram_sendmsg+0x5d4/0x132c net/unix/af_unix.c:2151
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x490/0x7c4 net/socket.c:2592
 ___sys_sendmsg+0x204/0x278 net/socket.c:2646
 __sys_sendmmsg+0x1f4/0x548 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2762 [inline]
 __se_sys_sendmmsg net/socket.c:2759 [inline]
 __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2759
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xb pfn:0x11a8d0
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
page_type: f0(buddy)
raw: 05ffc00000000000 fffffdffc36d8b88 fffffdffc36da808 0000000000000000
raw: 000000000000000b 0000000000000000 00000000f0000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000da8d0e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000da8d0f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000da8d0f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                       ^
 ffff0000da8d1000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000da8d1080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
ERROR: (device loop5): dtSearch: stack overrun!

btstack dump:
bn = 0, index = 0
bn = 20, index = 0
bn = 0, index = 0
bn = 20, index = 0
bn = 0, index = 0
bn = 20, index = 0
bn = 0, index = 0
bn = 0, index = 0
jfs_lookup: dtSearch returned -5