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

From: syzbot
Date: Tue Oct 15 2024 - 05:05:26 EST


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@xxxxxxxxxxxxxxxxx>
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@xxxxxxxxxxxxxxxxxxxxxxxxx
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>


---
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