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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: 0 PID: 17446 Comm: syz-executor0 Not tainted 4.9.113-g47bbcd6 #10
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88019c6d9800 task.stack: ffff8801a7468000
RIP: 0010:[<ffffffff81622397>]  [<ffffffff81622397>] mark_buffer_dirty_inode+0x1a7/0x200 fs/buffer.c:606
RSP: 0018:ffff8801a746f240  EFLAGS: 00010212
RAX: 0000000000040000 RBX: ffff880194c48738 RCX: ffffc90000915000
RDX: 0000000000004893 RSI: ffffffff81622397 RDI: ffff880197406320
RBP: ffff8801a746f270 R08: ffff88019c6da138 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801974061c8
R13: ffff8801d6142048 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f59024f4700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2cd22000 CR3: 00000001da163000 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 0000000000000000 ffff8801a746f430 ffff8801b7cf8220 000000000fffffff
 ffff8801a746f430 dffffc0000000000 ffff8801a746f2a0 ffffffff818c40f7
 ffff8801a746f2a0 ffff8801a746f570 0000000000000000 0000000000000008
Call Trace:
 [<ffffffff818c40f7>] fat32_ent_put+0xc7/0x120 fs/fat/fatent.c:189
 [<ffffffff818c6f9c>] fat_alloc_clusters+0x5ac/0xe10 fs/fat/fatent.c:499
 [<ffffffff818d40df>] fat_add_cluster+0x6f/0xe0 fs/fat/inode.c:100
 [<ffffffff818d442f>] __fat_get_block fs/fat/inode.c:147 [inline]
 [<ffffffff818d442f>] fat_get_block+0x2df/0x800 fs/fat/inode.c:176
 [<ffffffff81629f81>] __block_write_begin_int+0x391/0x1040 fs/buffer.c:1987
 [<ffffffff8162accf>] __block_write_begin fs/buffer.c:2038 [inline]
 [<ffffffff8162accf>] block_write_begin+0x5f/0x180 fs/buffer.c:2097
 [<ffffffff8162b2e3>] cont_write_begin+0x4f3/0x810 fs/buffer.c:2450
 [<ffffffff818d059a>] fat_write_begin+0x9a/0x120 fs/fat/inode.c:222
 [<ffffffff814330bd>] pagecache_write_begin+0x8d/0xc0 mm/filemap.c:2587
 [<ffffffff8162afef>] cont_expand_zero fs/buffer.c:2375 [inline]
 [<ffffffff8162afef>] cont_write_begin+0x1ff/0x810 fs/buffer.c:2440
 [<ffffffff818d059a>] fat_write_begin+0x9a/0x120 fs/fat/inode.c:222
 [<ffffffff814330bd>] pagecache_write_begin+0x8d/0xc0 mm/filemap.c:2587
 [<ffffffff81622cd0>] generic_cont_expand_simple+0x120/0x170 fs/buffer.c:2338
 [<ffffffff818c842d>] fat_cont_expand+0x6d/0x270 fs/fat/file.c:193
 [<ffffffff818c8785>] fat_fallocate+0x155/0x2d0 fs/fat/file.c:271
 [<ffffffff81568809>] vfs_fallocate+0x359/0x600 fs/open.c:329
 [<ffffffff8156b713>] SYSC_fallocate fs/open.c:352 [inline]
 [<ffffffff8156b713>] SyS_fallocate+0x53/0x90 fs/open.c:346
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9f93>] 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 23 72 3d 02 e9 56 ff ff ff e8 d9 c6 d3 ff <0f> 0b 4c 89 ef e8 7f 98 f1 ff e9 3b ff ff ff e8 75 98 f1 ff e9 
RIP  [<ffffffff81622397>] mark_buffer_dirty_inode+0x1a7/0x200 fs/buffer.c:606
 RSP <ffff8801a746f240>
---[ end trace e89b5bf8c3382b51 ]---