[syzbot] [iomap?] WARNING in iomap_iter (3)

[syzbot] [iomap?] WARNING in iomap_iter (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    d61a00525464 Add linux-next specific files for 20241011
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=175a3b27980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8554528c7f4bf3fb
dashboard link: https://syzkaller.appspot.com/bug?extid=74cc7d98ae5484c2744d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1513b840580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1313b840580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f615720e9964/disk-d61a0052.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c4a45c7583c6/vmlinux-d61a0052.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d767ab86d0d0/bzImage-d61a0052.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/fce276498eea/mount_0.gz

The issue was bisected to:

commit 56bd565ea59192bbc7d5bbcea155e861a20393f4
Author: Gao Xiang <hsiangkao@linux.alibaba.com>
Date:   Thu Oct 10 09:04:20 2024 +0000

    erofs: get rid of kaddr in `struct z_erofs_maprecorder`

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=11fd305f980000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=13fd305f980000
console output: https://syzkaller.appspot.com/x/log.txt?x=15fd305f980000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+74cc7d98ae5484c2744d@syzkaller.appspotmail.com
Fixes: 56bd565ea591 ("erofs: get rid of kaddr in `struct z_erofs_maprecorder`")

erofs: (device loop0): mounted with root inode @ nid 36.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 5233 at fs/iomap/iter.c:51 iomap_iter_done fs/iomap/iter.c:51 [inline]
WARNING: CPU: 1 PID: 5233 at fs/iomap/iter.c:51 iomap_iter+0x9db/0xf60 fs/iomap/iter.c:95
Modules linked in:
CPU: 1 UID: 0 PID: 5233 Comm: syz-executor323 Not tainted 6.12.0-rc2-next-20241011-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:iomap_iter_done fs/iomap/iter.c:51 [inline]
RIP: 0010:iomap_iter+0x9db/0xf60 fs/iomap/iter.c:95
Code: 0f 0b 90 e9 0a f9 ff ff e8 d2 10 62 ff 90 0f 0b 90 e9 42 fd ff ff e8 c4 10 62 ff 90 0f 0b 90 e9 71 fd ff ff e8 b6 10 62 ff 90 <0f> 0b 90 e9 d5 fd ff ff e8 a8 10 62 ff 90 0f 0b 90 43 80 3c 2e 00
RSP: 0018:ffffc900036af6e0 EFLAGS: 00010293
RAX: ffffffff8232e26a RBX: 0000000000004000 RCX: ffff88802b559e00
RDX: 0000000000000000 RSI: 0000000000018057 RDI: 0000000000004000
RBP: 0000000000018057 R08: ffffffff8232e03a R09: 1ffffd40001490be
R10: dffffc0000000000 R11: fffff940001490bf R12: 1ffff920006d5f05
R13: dffffc0000000000 R14: 1ffff920006d5f04 R15: ffffc900036af820
FS:  000055556b120380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000066c7e0 CR3: 000000007edfe000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 iomap_fiemap+0x73b/0x9b0 fs/iomap/fiemap.c:80
 ioctl_fiemap fs/ioctl.c:220 [inline]
 do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893
 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: 0033:0x7f5ca9685679
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd8eaa5b98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffd8eaa5d68 RCX: 00007f5ca9685679
RDX: 0000000020000040 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 00007f5ca96f8610 R08: 0000000000000000 R09: 00007ffd8eaa5d68
R10: 00000000000001e1 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd8eaa5d58 R14: 0000000000000001 R15: 0000000000000001
 </TASK>


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [iomap?] WARNING in iomap_iter (3)

[Gao Xiang]

Hi,

On 2024/10/15 17:03, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    d61a00525464 Add linux-next specific files for 20241011
> git tree:       linux-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=175a3b27980000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=8554528c7f4bf3fb
> dashboard link: https://syzkaller.appspot.com/bug?extid=74cc7d98ae5484c2744d
> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1513b840580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1313b840580000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/f615720e9964/disk-d61a0052.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/c4a45c7583c6/vmlinux-d61a0052.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/d767ab86d0d0/bzImage-d61a0052.xz
> mounted in repro: https://storage.googleapis.com/syzbot-assets/fce276498eea/mount_0.gz
> 
> The issue was bisected to:
> 
> commit 56bd565ea59192bbc7d5bbcea155e861a20393f4
> Author: Gao Xiang <hsiangkao@linux.alibaba.com>
> Date:   Thu Oct 10 09:04:20 2024 +0000
> 
>      erofs: get rid of kaddr in `struct z_erofs_maprecorder`

I will look into that, but it seems it's just a trivial cleanup,
not quite sure what happens here...

Thanks,
Gao Xiang

Re: [syzbot] [iomap?] WARNING in iomap_iter (3)

[Gao Xiang]

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git next-20241014

Re: [syzbot] [iomap?] WARNING in iomap_iter (3)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+74cc7d98ae5484c2744d@syzkaller.appspotmail.com
Tested-by: syzbot+74cc7d98ae5484c2744d@syzkaller.appspotmail.com

Tested on:

commit:         7f773fd6 Add linux-next specific files for 20241014
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git next-20241014
console output: https://syzkaller.appspot.com/x/log.txt?x=138ad727980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=4d6083ad781cbf8
dashboard link: https://syzkaller.appspot.com/bug?extid=74cc7d98ae5484c2744d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [iomap?] WARNING in iomap_iter (3)

[Gao Xiang]

another one:
#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git erofs-for-6.12-rc4-fixes

Re: [syzbot] [iomap?] WARNING in iomap_iter (3)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+74cc7d98ae5484c2744d@syzkaller.appspotmail.com
Tested-by: syzbot+74cc7d98ae5484c2744d@syzkaller.appspotmail.com

Tested on:

commit:         ae54567e erofs: get rid of kaddr in `struct z_erofs_ma..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git erofs-for-6.12-rc4-fixes
console output: https://syzkaller.appspot.com/x/log.txt?x=17bac030580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=286b31f2cf1c36b5
dashboard link: https://syzkaller.appspot.com/bug?extid=74cc7d98ae5484c2744d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [iomap?] WARNING in iomap_iter (3)

[Gao Xiang]

On 2024/10/15 17:10, Gao Xiang wrote:
> Hi,
> 
> On 2024/10/15 17:03, syzbot wrote:
>> Hello,
>>
>> syzbot found the following issue on:
>>
>> HEAD commit:    d61a00525464 Add linux-next specific files for 20241011
>> git tree:       linux-next

..

>>
>> commit 56bd565ea59192bbc7d5bbcea155e861a20393f4
>> Author: Gao Xiang <hsiangkao@linux.alibaba.com>
>> Date:   Thu Oct 10 09:04:20 2024 +0000
>>
>>      erofs: get rid of kaddr in `struct z_erofs_maprecorder`
> 
> I will look into that, but it seems it's just a trivial cleanup,
> not quite sure what happens here...

It seems that it's only caused by an outdated version in
next-20241011, which doesn't impact to upstream or the
latest -next:
https://lore.kernel.org/r/670e399e.050a0220.d9b66.014e.GAE@google.com
https://lore.kernel.org/r/670e3f3f.050a0220.f16b.000b.GAE@google.com

so

#syz set subsystems: erofs

#syz invalid