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truncate spotted in mem i_size < btree i_size: 128 < 134283264
WARNING: CPU: 0 PID: 6956 at fs/bcachefs/fs-io.c:457 bchfs_truncate+0xaaa/0xb70 fs/bcachefs/fs-io.c:454
Modules linked in:
CPU: 0 UID: 0 PID: 6956 Comm: syz.6.98 Not tainted 6.15.0-rc4-syzkaller-00021-gca91b9500108 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:bchfs_truncate+0xaaa/0xb70 fs/bcachefs/fs-io.c:454
Code: 00 74 0a 48 8b 7c 24 18 e8 23 bd ee fd 4c 8b 7c 24 18 49 8b 37 48 8b 94 24 00 01 00 00 48 c7 c7 a0 1a b4 8b e8 87 4b 53 fd 90 <0f> 0b 90 90 e9 31 fa ff ff e8 98 ed 8e fd 4c 8b 7c 24 50 4c 89 ff
RSP: 0018:ffffc900042df5a0 EFLAGS: 00010246
RAX: 5d841ef5ba8d0f00 RBX: 1ffff1100b94f188 RCX: ffff8880272f3c00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc900042df7f0 R08: ffff8880b8823e93 R09: 1ffff110171047d2
R10: dffffc0000000000 R11: ffffed10171047d3 R12: ffff88805ca78c40
R13: ffff88805ca78d00 R14: 0000000000000080 R15: ffff88805ca787e8
FS:  00007f6f0d9d56c0(0000) GS:ffff888126103000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6fb434f000 CR3: 000000002fb8c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 notify_change+0xb33/0xe40 fs/attr.c:552
 do_truncate+0x19a/0x220 fs/open.c:65
 handle_truncate fs/namei.c:3501 [inline]
 do_open fs/namei.c:3884 [inline]
 path_openat+0x306c/0x3830 fs/namei.c:4039
 do_filp_open+0x1fa/0x410 fs/namei.c:4066
 do_sys_openat2+0x121/0x1c0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_open fs/open.c:1452 [inline]
 __se_sys_open fs/open.c:1448 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1448
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f0fb8e969
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:00007f6f0d9d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f6f0fdb6160 RCX: 00007f6f0fb8e969
RDX: 0000000000000000 RSI: 000000000014927e RDI: 0000200000000180
RBP: 00007f6f0fc10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f6f0fdb6160 R15: 00007fffabb77718
 </TASK>