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kernel BUG at fs/buffer.c:606!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 15426 Comm: syz-executor0 Not tainted 4.9.109-ge1815b3 #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801c6a2c800 task.stack: ffff8801c41c8000
RIP: 0010:[<ffffffff816221e7>]  [<ffffffff816221e7>] mark_buffer_dirty_inode+0x1a7/0x200 fs/buffer.c:606
RSP: 0018:ffff8801c41cfb88  EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff8801b66ac738 RCX: ffffc9000810d000
RDX: 0000000000040000 RSI: ffffffff816221e7 RDI: ffff880185e44460
RBP: ffff8801c41cfbb8 R08: ffff8801c6a2d110 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff880185e44308
R13: ffff8801d6197688 R14: 0000000000000000 R15: 00000000000013a0
FS:  00007f0536829700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4357f12518 CR3: 0000000195276000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 00000001c41cfbb0 ffff8801c41cfd00 ffff8801bc72893e 00000000000013a0
 0000000000000000 00000000000013a0 ffff8801c41cfbe8 ffffffff818c3495
 ffff880185e44110 ffff8801c41cfd00 ffff8801d371c400 ffffffff83d12c40
Call Trace:
 [<ffffffff818c3495>] fat16_ent_put+0xc5/0x100 fs/fat/fatent.c:181
 [<ffffffff818c5dc5>] fat_ent_write+0xc5/0x190 fs/fat/fatent.c:413
 [<ffffffff818d648c>] fat_chain_add+0x44c/0x610 fs/fat/misc.c:128
 [<ffffffff818d35cf>] fat_add_cluster+0xbf/0xe0 fs/fat/inode.c:105
 [<ffffffff818c7d0c>] fat_fallocate+0x23c/0x2d0 fs/fat/file.c:262
 [<ffffffff815686b9>] vfs_fallocate+0x359/0x600 fs/open.c:329
 [<ffffffff8156b5c3>] SYSC_fallocate fs/open.c:352 [inline]
 [<ffffffff8156b5c3>] SyS_fallocate+0x53/0x90 fs/open.c:346
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9993>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: ea 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 f7 e8 c3 6d 3d 02 e9 56 ff ff ff e8 59 c7 d3 ff <0f> 0b 4c 89 ef e8 df 98 f1 ff e9 3b ff ff ff e8 d5 98 f1 ff e9 
RIP  [<ffffffff816221e7>] mark_buffer_dirty_inode+0x1a7/0x200 fs/buffer.c:606
 RSP <ffff8801c41cfb88>
---[ end trace b471b5635dacc4eb ]---