syzbot

 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
------------[ cut here ]------------
kernel BUG at mm/filemap.c:166!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 4353 Comm: syz.0.17 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:unaccount_page_cache_page+0x75c/0x870 mm/filemap.c:166
Code: e8 e9 70 db ff 4c 89 f7 48 c7 c6 e0 e4 12 8a e8 aa db 0d 00 0f 0b e8 d3 70 db ff 4c 89 f7 48 c7 c6 20 e5 12 8a e8 94 db 0d 00 <0f> 0b 48 85 ed 75 59 e8 b8 70 db ff eb 5d e8 b1 70 db ff 4c 89 f7
RSP: 0018:ffffc9000334f688 EFLAGS: 00010046
RAX: 3749e65dd1ec9600 RBX: 0000000000000000 RCX: ffff888023001dc0
RDX: 0000000000000000 RSI: 000000000000ffff RDI: 000000000000ffff
RBP: 1ffffd400034d7d9 R08: dffffc0000000000 R09: ffffed1017224f24
R10: ffffed1017224f24 R11: 1ffff11017224f23 R12: ffffea0001a6bec0
R13: dffffc0000000000 R14: ffffea0001a6bec0 R15: ffffea0001a6bec8
FS:  000055556c3f9500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000280 CR3: 000000001e731000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __delete_from_page_cache+0xbf/0x6b0 mm/filemap.c:231
 delete_from_page_cache+0x121/0x190 mm/filemap.c:266
 truncate_inode_page+0x8d/0xb0 mm/truncate.c:219
 shmem_undo_range+0x49b/0x1840 mm/shmem.c:960
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x20d/0xa00 mm/shmem.c:1145
 evict+0x485/0x870 fs/inode.c:647
 __dentry_kill+0x431/0x650 fs/dcache.c:586
 dentry_kill+0xb8/0x290 fs/dcache.c:-1
 dput+0xd8/0x1a0 fs/dcache.c:893
 __fput+0x5ee/0x930 fs/file_table.c:319
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc157acebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd83c04038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00000000000131c1 RCX: 00007fc157acebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000883c0432f
R10: 0000001b2fd20000 R11: 0000000000000246 R12: 00007fc157cf5fac
R13: 00007fc157cf5fa0 R14: ffffffffffffffff R15: 0000000000000003
 </TASK>
Modules linked in:
---[ end trace 9eea126791e88ec5 ]---
RIP: 0010:unaccount_page_cache_page+0x75c/0x870 mm/filemap.c:166
Code: e8 e9 70 db ff 4c 89 f7 48 c7 c6 e0 e4 12 8a e8 aa db 0d 00 0f 0b e8 d3 70 db ff 4c 89 f7 48 c7 c6 20 e5 12 8a e8 94 db 0d 00 <0f> 0b 48 85 ed 75 59 e8 b8 70 db ff eb 5d e8 b1 70 db ff 4c 89 f7
RSP: 0018:ffffc9000334f688 EFLAGS: 00010046
RAX: 3749e65dd1ec9600 RBX: 0000000000000000 RCX: ffff888023001dc0
RDX: 0000000000000000 RSI: 000000000000ffff RDI: 000000000000ffff
RBP: 1ffffd400034d7d9 R08: dffffc0000000000 R09: ffffed1017224f24
R10: ffffed1017224f24 R11: 1ffff11017224f23 R12: ffffea0001a6bec0
R13: dffffc0000000000 R14: ffffea0001a6bec0 R15: ffffea0001a6bec8
FS:  000055556c3f9500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000280 CR3: 000000001e731000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400