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kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
kobject: 'loop0' (ffff8880842801e0): kobject_uevent_env
Modules linked in:
CPU: 1 PID: 23039 Comm: syz-executor.0 Not tainted 4.14.136 #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88809cccc5c0 task.stack: ffff888052338000
RIP: 0010:mark_buffer_dirty_inode fs/buffer.c:605 [inline]
RIP: 0010:mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596
RSP: 0018:ffff88805233f258 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88807f94db28 RCX: ffffc90006ab1000
RDX: 0000000000040000 RSI: ffffffff81994cba RDI: ffff888094064ef8
RBP: ffff88805233f290 R08: ffff88809cccc5c0 R09: 0000000000000003
R10: 0000000000000000 R11: ffff88809cccc5c0 R12: ffff888094064d98
R13: 0000000000000000 R14: ffff8880881d8a60 R15: ffff88805233f510
FS:  00007fb2e6f27700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe465f79518 CR3: 00000000551a9000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat16_ent_put+0xc5/0x100 fs/fat/fatent.c:181
kobject: 'loop0' (ffff8880842801e0): fill_kobj_path: path = '/devices/virtual/block/loop0'
 fat_alloc_clusters+0x5a4/0xdb0 fs/fat/fatent.c:499
 fat_add_cluster+0x60/0xc0 fs/fat/inode.c:100
 __fat_get_block fs/fat/inode.c:147 [inline]
 fat_get_block+0x2d4/0x7e0 fs/fat/inode.c:176
 __block_write_begin_int+0x396/0x1100 fs/buffer.c:2027
 __block_write_begin fs/buffer.c:2077 [inline]
 block_write_begin+0x5f/0x190 fs/buffer.c:2136
 cont_write_begin+0x430/0x770 fs/buffer.c:2486
 fat_write_begin+0x8d/0x120 fs/fat/inode.c:222
 pagecache_write_begin+0x84/0xc0 mm/filemap.c:2890
 cont_expand_zero fs/buffer.c:2413 [inline]
 cont_write_begin+0x206/0x770 fs/buffer.c:2476
 fat_write_begin+0x8d/0x120 fs/fat/inode.c:222
 pagecache_write_begin+0x84/0xc0 mm/filemap.c:2890
 generic_cont_expand_simple+0xeb/0x130 fs/buffer.c:2377
 fat_cont_expand+0x71/0x280 fs/fat/file.c:198
 fat_setattr+0x8a1/0xae0 fs/fat/file.c:477
 notify_change+0x8d1/0xd10 fs/attr.c:313
 do_truncate+0x124/0x1c0 fs/open.c:63
 vfs_truncate+0x477/0x690 fs/open.c:120
 do_sys_truncate.part.0+0xdf/0xf0 fs/open.c:143
 do_sys_truncate fs/open.c:137 [inline]
 SYSC_truncate fs/open.c:155 [inline]
 SyS_truncate+0x28/0x50 fs/open.c:153
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459829
RSP: 002b:00007fb2e6f26c78 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459829
RDX: 0000000000000000 RSI: 0000000000090002 RDI: 0000000020000240
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb2e6f276d4
R13: 00000000004c0263 R14: 00000000004dff78 R15: 00000000ffffffff
Code: fa 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 4d 4c 89 63 58 4c 89 ef e8 90 8e 82 04 e9 13 fe ff ff e8 e6 78 c3 ff <0f> 0b 4c 89 ff e8 5c 25 ed ff e9 f8 fd ff ff e8 52 25 ed ff e9 
RIP: mark_buffer_dirty_inode fs/buffer.c:605 [inline] RSP: ffff88805233f258
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596 RSP: ffff88805233f258
---[ end trace 5a2d537e3e8a33ff ]---