syzbot

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kernel BUG at fs/buffer.c:2785!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 6383 Comm: syz.0.111 Not tainted 6.12.0-rc3-syzkaller-00044-g2f87d0916ce0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:submit_bh_wbc+0x556/0x560 fs/buffer.c:2785
Code: 89 fa e8 5d 6f cc 02 e9 95 fe ff ff e8 a3 98 74 ff 90 0f 0b e8 9b 98 74 ff 90 0f 0b e8 93 98 74 ff 90 0f 0b e8 8b 98 74 ff 90 <0f> 0b e8 83 98 74 ff 90 0f 0b 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900042a7358 EFLAGS: 00010287
RAX: ffffffff82204e75 RBX: 0000000000000154 RCX: 0000000000040000
RDX: ffffc90015576000 RSI: 0000000000000516 RDI: 0000000000000517
RBP: 0000000000000100 R08: ffffffff82204a39 R09: 1ffff1100b7ecb22
R10: dffffc0000000000 R11: ffffed100b7ecb23 R12: 0000000000000000
R13: ffff88805bf65910 R14: 0000000000000000 R15: 1ffff1100b7ecb22
FS:  00007f7cc825a6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000002c4a2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 submit_bh fs/buffer.c:2824 [inline]
 block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2451
 do_mpage_readpage+0x1a73/0x1c80 fs/mpage.c:317
 mpage_read_folio+0x108/0x1e0 fs/mpage.c:392
 filemap_read_folio+0x14b/0x630 mm/filemap.c:2367
 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3825
 do_read_cache_page+0x30/0x200 mm/filemap.c:3891
 read_mapping_page include/linux/pagemap.h:1005 [inline]
 page_get_link+0x56/0x4a0 fs/namei.c:5319
 pick_link+0x631/0xd50
 step_into+0xca9/0x1080 fs/namei.c:1923
 lookup_last fs/namei.c:2556 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2580
 filename_lookup+0x256/0x610 fs/namei.c:2609
 user_path_at+0x3a/0x60 fs/namei.c:3016
 do_mount fs/namespace.c:3844 [inline]
 __do_sys_mount fs/namespace.c:4055 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:4032
 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: 0033:0x7f7cc737dff9
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:00007f7cc825a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f7cc7535f80 RCX: 00007f7cc737dff9
RDX: 0000000020000000 RSI: 0000000020000040 RDI: 0000000000000000
RBP: 00007f7cc73f0296 R08: 0000000020000100 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7cc7535f80 R15: 00007ffc70fa92e8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:submit_bh_wbc+0x556/0x560 fs/buffer.c:2785
Code: 89 fa e8 5d 6f cc 02 e9 95 fe ff ff e8 a3 98 74 ff 90 0f 0b e8 9b 98 74 ff 90 0f 0b e8 93 98 74 ff 90 0f 0b e8 8b 98 74 ff 90 <0f> 0b e8 83 98 74 ff 90 0f 0b 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900042a7358 EFLAGS: 00010287
RAX: ffffffff82204e75 RBX: 0000000000000154 RCX: 0000000000040000
RDX: ffffc90015576000 RSI: 0000000000000516 RDI: 0000000000000517
RBP: 0000000000000100 R08: ffffffff82204a39 R09: 1ffff1100b7ecb22
R10: dffffc0000000000 R11: ffffed100b7ecb23 R12: 0000000000000000
R13: ffff88805bf65910 R14: 0000000000000000 R15: 1ffff1100b7ecb22
FS:  00007f7cc825a6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000002c4a2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400