------------[ cut here ]------------
truncate spotted in mem i_size < btree i_size: 10 < 1048576
WARNING: CPU: 0 PID: 5326 at fs/bcachefs/fs-io.c:428 bchfs_truncate+0xbca/0xc90 fs/bcachefs/fs-io.c:425
Modules linked in:
CPU: 0 UID: 0 PID: 5326 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-12113-gbcc8eda6d349 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:bchfs_truncate+0xbca/0xc90 fs/bcachefs/fs-io.c:425
Code: fc ff df 41 80 3c 06 00 74 08 48 89 df e8 1e 67 cb fd 48 8b 94 24 20 01 00 00 48 c7 c7 00 2a 52 8c 4c 89 fe e8 17 27 21 fd 90 <0f> 0b 90 90 e9 cf f9 ff ff e8 28 7f 60 fd 48 8b 5c 24 60 48 89 df
RSP: 0018:ffffc9000d4c7500 EFLAGS: 00010246
RAX: 96c9b74a7a7eca00 RBX: ffffc9000d4c7620 RCX: ffff88801cff8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000d4c7778 R08: ffffffff81601c02 R09: 1ffff11003f8519a
R10: dffffc0000000000 R11: ffffed1003f8519b R12: 1ffff1100a940183
R13: ffff888054a007d0 R14: 1ffff92001a98ec4 R15: 000000000000000a
FS:  00007fcb1e2306c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000043a40000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 notify_change+0xbca/0xe90 fs/attr.c:552
 do_truncate+0x220/0x310 fs/open.c:65
 handle_truncate fs/namei.c:3449 [inline]
 do_open fs/namei.c:3832 [inline]
 path_openat+0x2e1e/0x3590 fs/namei.c:3987
 do_filp_open+0x27f/0x4e0 fs/namei.c:4014
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_creat fs/open.c:1495 [inline]
 __se_sys_creat fs/open.c:1489 [inline]
 __x64_sys_creat+0x123/0x170 fs/open.c:1489
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcb1d380849
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:00007fcb1e230058 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fcb1d546160 RCX: 00007fcb1d380849
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000440
RBP: 00007fcb1d3f3986 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fcb1d546160 R15: 00007ffc0a1b0f28
 </TASK>