[syzbot] [iomap?] WARNING in iomap_zero_iter

syzbot
2024-12-02T01:48:29Z

Hello,

syzbot found the following issue on:

HEAD commit: b86545e02e8c Merge tag 'acpi-6.13-rc1-2' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=107623c0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5f0b9d4913852126
dashboard link: https://syzkaller.appspot.com/bug?extid=af7e25f0384dc888e1bf
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-b86545e0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/00ec87aaa7ee/vmlinux-b86545e0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fcc70e20d51b/bzImage-b86545e0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+af7e25f0384dc888e1bf@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
gfs2: fsid=syz:syz: Trying to join cluster "lock_nolock", "syz:syz"
gfs2: fsid=syz:syz: Now mounting FS (format 1801)...
gfs2: fsid=syz:syz.0: journal 0 mapped with 1 extents in 0ms
gfs2: fsid=syz:syz.0: first mount done, others may mount
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5341 at fs/iomap/buffered-io.c:1373 iomap_zero_iter+0x3b3/0x4c0 fs/iomap/buffered-io.c:1373
Modules linked in:
CPU: 0 UID: 0 PID: 5341 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-10553-gb86545e02e8c #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:iomap_zero_iter+0x3b3/0x4c0 fs/iomap/buffered-io.c:1373
Code: 85 ff 49 bc 00 00 00 00 00 fc ff df 7e 56 49 01 dd e8 21 66 60 ff 48 8b 1c 24 48 8d 4c 24 60 e9 0b fe ff ff e8 0e 66 60 ff 90 <0f> 0b 90 e9 1b ff ff ff 48 8b 4c 24 10 80 e1 07 fe c1 38 c1 0f 8c
RSP: 0018:ffffc9000d27f3e0 EFLAGS: 00010283
RAX: ffffffff82357e72 RBX: 0000000000000000 RCX: 0000000000100000
RDX: ffffc9000e2fa000 RSI: 000000000000053d RDI: 000000000000053e
RBP: ffffc9000d27f4b0 R08: ffffffff82357d88 R09: 1ffffd40002a07d8
R10: dffffc0000000000 R11: fffff940002a07d9 R12: 0000000000008000
R13: 0000000000008000 R14: ffffea0001503ec0 R15: 0000000000000001
FS: 00007efeb79fe6c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efeb81360e8 CR3: 00000000442d8000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
iomap_zero_range+0x69b/0x970 fs/iomap/buffered-io.c:1456
gfs2_block_zero_range fs/gfs2/bmap.c:1303 [inline]
__gfs2_punch_hole+0x311/0xb30 fs/gfs2/bmap.c:2420
gfs2_fallocate+0x3a1/0x490 fs/gfs2/file.c:1399
vfs_fallocate+0x569/0x6e0 fs/open.c:327
do_vfs_ioctl+0x258c/0x2e40 fs/ioctl.c:885
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl+0x80/0x170 fs/ioctl.c:892
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: 0033:0x7efeb7f80809
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:00007efeb79fe058 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007efeb8145fa0 RCX: 00007efeb7f80809
RDX: 0000000020000000 RSI: 0000000040305829 RDI: 0000000000000005
RBP: 00007efeb7ff393e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007efeb8145fa0 R15: 00007ffd994f7a38
</TASK>

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