[syzbot] [erofs?] WARNING in get_next_unlocked_entry

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e927c520e1ba Merge tag 'loongarch-fixes-6.18-1' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=129957cd980000
kernel config: https://syzkaller.appspot.com/x/.config?x=929790bc044e87d7
dashboard link: https://syzkaller.appspot.com/bug?extid=31b8fb02cb8a25bd5e78
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16994692580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16d58d32580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-e927c520.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/924fb782edf1/vmlinux-e927c520.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7e6af189c28e/bzImage-e927c520.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6a0aec9d15b8/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=1740497c580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+31b8fb...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 16
erofs (device loop0): mounted with root inode @ nid 36.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5492 at fs/dax.c:224 get_next_unlocked_entry+0x329/0x340 fs/dax.c:224
Modules linked in:
CPU: 0 UID: 0 PID: 5492 Comm: syz.0.17 Not tainted syzkaller #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:get_next_unlocked_entry+0x329/0x340 fs/dax.c:224
Code: 45 1d 10 48 3b 84 24 c0 00 00 00 75 22 4c 89 e8 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 3e 8a f9 08 cc e8 08 59 6e ff 90 <0f> 0b 90 eb a0 e8 6d a6 f6 08 66 66 66 66 2e 0f 1f 84 00 00 00 00
RSP: 0018:ffffc90002b7e8a0 EFLAGS: 00010093
RAX: ffffffff8251ba68 RBX: 1ffff9200056fd9c RCX: ffff8880354e4900
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002b7e9b0 R08: ffffc90002b7e937 R09: 0000000000000000
R10: ffffc90002b7e900 R11: fffff5200056fd27 R12: ffffc90002b7e918
R13: ffffea00010af380 R14: ffffc90002b7e900 R15: dffffc0000000000
FS: 0000555581eb2500(0000) GS:ffff88808d730000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557f23763138 CR3: 00000000424dd000 CR4: 0000000000352ef0
Call Trace:
<TASK>
grab_mapping_entry+0x176/0x660 fs/dax.c:660
dax_iomap_pte_fault fs/dax.c:1891 [inline]
dax_iomap_fault+0x8ab/0x18d0 fs/dax.c:2080
__do_fault+0x138/0x390 mm/memory.c:5281
do_cow_fault mm/memory.c:5746 [inline]
do_fault mm/memory.c:5852 [inline]
do_pte_missing mm/memory.c:4362 [inline]
handle_pte_fault mm/memory.c:6195 [inline]
__handle_mm_fault+0x1719/0x5400 mm/memory.c:6336
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6505
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0x165c/0x2a00 mm/gup.c:1428
__get_user_pages_locked mm/gup.c:1692 [inline]
get_user_pages_remote+0x2f1/0xac0 mm/gup.c:2614
uprobe_write+0x1b6/0x2160 kernel/events/uprobes.c:529
uprobe_write_opcode+0xa8/0xf0 kernel/events/uprobes.c:493
set_swbp+0x121/0x290 arch/x86/kernel/uprobes.c:1090
install_breakpoint+0x451/0x5a0 kernel/events/uprobes.c:1170
register_for_each_vma+0xabb/0xc30 kernel/events/uprobes.c:1315
uprobe_apply+0xfb/0x270 kernel/events/uprobes.c:1459
uprobe_perf_open kernel/trace/trace_uprobe.c:1371 [inline]
trace_uprobe_register+0x4df/0x560 kernel/trace/trace_uprobe.c:1533
perf_trace_event_open kernel/trace/trace_event_perf.c:184 [inline]
perf_trace_event_init+0x19a/0x9d0 kernel/trace/trace_event_perf.c:206
perf_uprobe_init+0x12e/0x1a0 kernel/trace/trace_event_perf.c:332
perf_uprobe_event_init+0xe6/0x180 kernel/events/core.c:11170
perf_try_init_event+0x17f/0x870 kernel/events/core.c:12615
perf_init_event kernel/events/core.c:12713 [inline]
perf_event_alloc+0x133e/0x2be0 kernel/events/core.c:12988
__do_sys_perf_event_open kernel/events/core.c:13506 [inline]
__se_sys_perf_event_open+0x772/0x1d70 kernel/events/core.c:13387
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe38998f6c9
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:00007ffe19690378 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007fe389be5fa0 RCX: 00007fe38998f6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000000c0
RBP: 00007fe389a11f91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe389be5fa0 R14: 00007fe389be5fa0 R15: 0000000000000005
</TASK>


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