linux-kernel - [syzbot] [f2fs?] kernel BUG in f2fs_truncate

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Message-ID: <68a68e27.050a0220.1a3988.0002.GAE@google.com>
Date: Wed, 20 Aug 2025 20:10:31 -0700
From: syzbot <syzbot+b9c7ffd609c3f09416ab@...kaller.appspotmail.com>
To: chao@...nel.org, jaegeuk@...nel.org, 
	linux-f2fs-devel@...ts.sourceforge.net, linux-kernel@...r.kernel.org, 
	syzkaller-bugs@...glegroups.com
Subject: [syzbot] [f2fs?] kernel BUG in f2fs_truncate_hole (2)

Hello,

syzbot found the following issue on:

HEAD commit:    90d970cade8e Merge tag 'ata-ata-6.17-rc2' of git://git.ker..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=118fb3a2580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3f81850843b877ed
dashboard link: https://syzkaller.appspot.com/bug?extid=b9c7ffd609c3f09416ab
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-90d970ca.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/746014c1cf11/vmlinux-90d970ca.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4f69411b895d/bzImage-90d970ca.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b9c7ffd609c3f09416ab@...kaller.appspotmail.com

 </TASK>
F2FS-fs (loop0): access invalid blkaddr:1818846767
CPU: 0 UID: 0 PID: 5354 Comm: syz.0.0 Not tainted 6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 __f2fs_is_valid_blkaddr+0xe52/0x14f0 fs/f2fs/checkpoint.c:213
 f2fs_truncate_data_blocks_range+0x790/0x1390 fs/f2fs/file.c:674
 f2fs_truncate_hole+0x3f2/0x6c0 fs/f2fs/file.c:1245
 f2fs_punch_hole+0x2db/0x330 fs/f2fs/file.c:1306
 f2fs_fallocate+0x546/0x990 fs/f2fs/file.c:2018
 vfs_fallocate+0x666/0x7e0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e65f8ebe9
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:00007f1e66dd1038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f1e661b6090 RCX: 00007f1e65f8ebe9
RDX: 0000000000000003 RSI: 0000000000000003 RDI: 000000000000000a
RBP: 00007f1e66011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000404042bbe R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1e661b6128 R14: 00007f1e661b6090 R15: 00007ffe98c9dc98
 </TASK>
F2FS-fs (loop0): Inconsistent error blkaddr:12389, sit bitmap:0
CPU: 0 UID: 0 PID: 5354 Comm: syz.0.0 Not tainted 6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 __is_bitmap_valid fs/f2fs/checkpoint.c:168 [inline]
 __f2fs_is_valid_blkaddr+0xd84/0x14f0 fs/f2fs/checkpoint.c:216
 f2fs_truncate_data_blocks_range+0x790/0x1390 fs/f2fs/file.c:674
 f2fs_truncate_hole+0x3f2/0x6c0 fs/f2fs/file.c:1245
 f2fs_punch_hole+0x2db/0x330 fs/f2fs/file.c:1306
 f2fs_fallocate+0x546/0x990 fs/f2fs/file.c:2018
 vfs_fallocate+0x666/0x7e0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e65f8ebe9
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:00007f1e66dd1038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f1e661b6090 RCX: 00007f1e65f8ebe9
RDX: 0000000000000003 RSI: 0000000000000003 RDI: 000000000000000a
RBP: 00007f1e66011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000404042bbe R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1e661b6128 R14: 00007f1e661b6090 R15: 00007ffe98c9dc98
 </TASK>
------------[ cut here ]------------
kernel BUG at fs/f2fs/file.c:1243!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5354 Comm: syz.0.0 Not tainted 6.17.0-rc1-syzkaller-00211-g90d970cade8e #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:f2fs_truncate_hole+0x69e/0x6c0 fs/f2fs/file.c:1243
Code: 75 1d 89 d8 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 55 7b 7d 07 cc e8 af fa be fd eb a4 e8 58 96 7a 07 e8 a3 fa be fd 90 <0f> 0b e8 9b fa be fd 4c 89 ef 48 c7 c6 20 8c d1 8b e8 cc 3b 27 fd
RSP: 0018:ffffc9000eddfbe0 EFLAGS: 00010287
RAX: ffffffff8400c09d RBX: 0000000000000000 RCX: 0000000000100000
RDX: ffffc9000e523000 RSI: 0000000000072bb6 RDI: 0000000000072bb7
RBP: ffffc9000eddfd18 R08: ffff8880433a2887 R09: 1ffff11008674510
R10: dffffc0000000000 R11: ffffed1008674511 R12: 0000000000000360
R13: ffffffffffffffff R14: 0000000000404042 R15: 00000000000006c0
FS:  00007f1e66dd16c0(0000) GS:ffff88808d210000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e65fec470 CR3: 000000003f147000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 f2fs_punch_hole+0x2db/0x330 fs/f2fs/file.c:1306
 f2fs_fallocate+0x546/0x990 fs/f2fs/file.c:2018
 vfs_fallocate+0x666/0x7e0 fs/open.c:342
 ksys_fallocate fs/open.c:366 [inline]
 __do_sys_fallocate fs/open.c:371 [inline]
 __se_sys_fallocate fs/open.c:369 [inline]
 __x64_sys_fallocate+0xc0/0x110 fs/open.c:369
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1e65f8ebe9
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:00007f1e66dd1038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f1e661b6090 RCX: 00007f1e65f8ebe9
RDX: 0000000000000003 RSI: 0000000000000003 RDI: 000000000000000a
RBP: 00007f1e66011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000404042bbe R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1e661b6128 R14: 00007f1e661b6090 R15: 00007ffe98c9dc98
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:f2fs_truncate_hole+0x69e/0x6c0 fs/f2fs/file.c:1243
Code: 75 1d 89 d8 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 55 7b 7d 07 cc e8 af fa be fd eb a4 e8 58 96 7a 07 e8 a3 fa be fd 90 <0f> 0b e8 9b fa be fd 4c 89 ef 48 c7 c6 20 8c d1 8b e8 cc 3b 27 fd
RSP: 0018:ffffc9000eddfbe0 EFLAGS: 00010287
RAX: ffffffff8400c09d RBX: 0000000000000000 RCX: 0000000000100000
RDX: ffffc9000e523000 RSI: 0000000000072bb6 RDI: 0000000000072bb7
RBP: ffffc9000eddfd18 R08: ffff8880433a2887 R09: 1ffff11008674510
R10: dffffc0000000000 R11: ffffed1008674511 R12: 0000000000000360
R13: ffffffffffffffff R14: 0000000000404042 R15: 00000000000006c0
FS:  00007f1e66dd16c0(0000) GS:ffff88808d210000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e65fec470 CR3: 000000003f147000 CR4: 0000000000352ef0


---
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