syz.1.1368: attempt to access beyond end of device
loop1: rw=1, sector=1, nr_sectors = 1 limit=0
Buffer I/O error on dev loop1, logical block 1, lost sync page write
------------[ cut here ]------------
WARNING: CPU: 0 PID: 11104 at fs/buffer.c:1188 mark_buffer_dirty+0x2bb/0x4d0 fs/buffer.c:1188
Modules linked in:
CPU: 0 PID: 11104 Comm: syz.1.1368 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
RIP: 0010:mark_buffer_dirty+0x2bb/0x4d0 fs/buffer.c:1188
Code: 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 ef 93 fc ff e8 2a b0 87 ff 48 89 df 5b 41 5c 41 5e 41 5f 5d e9 9a ef e7 ff e8 15 b0 87 ff <0f> 0b e9 84 fd ff ff e8 09 b0 87 ff 0f 0b e9 b0 fd ff ff e8 fd af
RSP: 0018:ffffc900034f7198 EFLAGS: 00010287
RAX: ffffffff82002e8b RBX: ffff88805a7d53a0 RCX: 0000000000080000
RDX: ffffc90013e88000 RSI: 000000000000f641 RDI: 000000000000f642
RBP: ffff88802106cf01 R08: ffff88805a7d53a7 R09: 1ffff1100b4faa74
R10: dffffc0000000000 R11: ffffed100b4faa75 R12: dffffc0000000000
R13: ffff88805a577b58 R14: ffffea00016432d8 R15: 000000000fffffff
FS:  00007f5ffccf16c0(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcdf491e98 CR3: 000000006541d000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mark_buffer_dirty_inode+0x86/0x2c0 fs/buffer.c:681
 fat_ent_write+0xb2/0x180 fs/fat/fatent.c:417
 fat_chain_add+0x3e9/0x890 fs/fat/misc.c:140
 fat_add_cluster fs/fat/inode.c:113 [inline]
 __fat_get_block fs/fat/inode.c:155 [inline]
 fat_get_block+0x765/0xae0 fs/fat/inode.c:190
 __block_write_begin_int+0x571/0x1b00 fs/buffer.c:2124
 __block_write_begin fs/buffer.c:2173 [inline]
 block_write_begin+0x9a/0x1e0 fs/buffer.c:2234
 cont_write_begin+0x5fd/0x800 fs/buffer.c:2591
 fat_write_begin+0x97/0x160 fs/fat/inode.c:230
 cont_expand_zero fs/buffer.c:2551 [inline]
 cont_write_begin+0x659/0x800 fs/buffer.c:2581
 fat_write_begin+0x97/0x160 fs/fat/inode.c:230
 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4027
 generic_file_write_iter+0xaf/0x2e0 mm/filemap.c:4148
 do_iter_readv_writev fs/read_write.c:-1 [inline]
 do_iter_write+0x747/0xc50 fs/read_write.c:860
 vfs_writev fs/read_write.c:933 [inline]
 do_pwritev+0x242/0x3a0 fs/read_write.c:1030
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f5ffbd9fb19
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5ffccf1028 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f5ffc025fa0 RCX: 00007f5ffbd9fb19
RDX: 0000000000000001 RSI: 0000200000022500 RDI: 0000000000000005
RBP: 00007f5ffbe37b70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7b R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ffc026038 R14: 00007f5ffc025fa0 R15: 00007ffe60ac4c88
 </TASK>