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kernel BUG at fs/buffer.c:605!
loop_reread_partitions: partition scan of loop0 (�8�b�+�?���s�=7]c��I�ir�n���0�jub�x—J��t}̳c���YUB) failed (rc=-16)
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 12848 Comm: syz-executor.0 Not tainted 4.14.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888091284300 task.stack: ffff888015680000
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:ffff888015687260 EFLAGS: 00010216
RAX: 0000000000040000 RBX: ffff88803612d3f0 RCX: ffffc90008045000
RDX: 000000000001541e RSI: ffffffff819b288a RDI: ffff888015b1b9b8
RBP: ffff888015687298 R08: ffff888091284300 R09: 0000000000000002
R10: 0000000000000000 R11: ffff888091284300 R12: ffff888015b1b858
R13: 0000000000000000 R14: ffff8880a6e6e520 R15: ffff88805651e300
FS:  00007f750e348700(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000008bb028 CR3: 00000000756b6000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat_mirror_bhs+0x283/0x450 fs/fat/fatent.c:397
 fat_alloc_clusters+0xb28/0xdb0 fs/fat/fatent.c:542
 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/0x280 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:2891
 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:2891
 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
 do_sys_ftruncate.constprop.0+0x3bc/0x490 fs/open.c:205
 SYSC_ftruncate fs/open.c:215 [inline]
 SyS_ftruncate+0x1c/0x30 fs/open.c:213
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c449
RSP: 002b:00007f750e347c78 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00007f750e3486d4 RCX: 000000000045c449
RDX: 0000000000000000 RSI: 000000000200a000 RDI: 0000000000000005
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000e7 R14: 00000000004c32c9 R15: 000000000076bf2c
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 30 b3 cd 04 e9 13 fe ff ff e8 d6 9f c1 ff <0f> 0b 4c 89 ff e8 8c 2f ec ff e9 f8 fd ff ff e8 82 2f ec ff e9 
RIP: mark_buffer_dirty_inode fs/buffer.c:605 [inline] RSP: ffff888015687260
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596 RSP: ffff888015687260
---[ end trace ace54d05cc5e5b5f ]---