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kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
loop_set_block_size: loop0 () has still dirty pages (nrpages=15)
Modules linked in:
CPU: 0 PID: 11493 Comm: syz-executor.0 Not tainted 4.14.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88805b386600 task.stack: ffff88805b4c0000
RIP: 0010:mark_buffer_dirty_inode+0x2d8/0x3a0 fs/buffer.c:605
RSP: 0018:ffff88805b4c73b8 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff888056b17dc8 RCX: ffffc9000629c000
RDX: 0000000000040000 RSI: ffffffff8196db48 RDI: ffff88804f8aef10
RBP: ffff88804f8aedb0 R08: 0000000000000001 R09: 0000000000000002
R10: ffff88805b386ed8 R11: ffff88805b386600 R12: ffff8880a6d66a68
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff888051e1e8c0
FS:  00007fb35c0e9700(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000043e360 CR3: 00000000a8491000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat_mirror_bhs+0x27a/0x420 fs/fat/fatent.c:397
 fat_alloc_clusters+0xaab/0xcf0 fs/fat/fatent.c:542
 fat_add_cluster+0x5d/0xc0 fs/fat/inode.c:100
 __fat_get_block fs/fat/inode.c:147 [inline]
 fat_get_block+0x28f/0x750 fs/fat/inode.c:176
 __block_write_begin_int+0x33a/0x1000 fs/buffer.c:2038
 __block_write_begin fs/buffer.c:2088 [inline]
 block_write_begin+0x58/0x260 fs/buffer.c:2147
 cont_write_begin+0x480/0x720 fs/buffer.c:2497
 fat_write_begin+0x89/0x110 fs/fat/inode.c:222
 cont_expand_zero fs/buffer.c:2424 [inline]
 cont_write_begin+0x289/0x720 fs/buffer.c:2487
 fat_write_begin+0x89/0x110 fs/fat/inode.c:222
 generic_cont_expand_simple+0xd8/0x120 fs/buffer.c:2388
 fat_cont_expand+0x71/0x280 fs/fat/file.c:198
 fat_setattr+0x89d/0xad0 fs/fat/file.c:477
 notify_change+0x56b/0xd10 fs/attr.c:313
 do_truncate+0xff/0x1a0 fs/open.c:63
 do_sys_ftruncate.constprop.0+0x3a3/0x480 fs/open.c:205
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45cb29
RSP: 002b:00007fb35c0e8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00000000004dd320 RCX: 000000000045cb29
RDX: 0000000000000000 RSI: 0000000000208200 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000f2 R14: 00000000004c3abc R15: 00007fb35c0e96d4
Code: fa 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 4d 48 89 6b 58 4c 89 ef e8 62 78 a7 04 e9 20 fe ff ff e8 98 ca c3 ff <0f> 0b 4c 89 ff e8 2e 04 ed ff e9 05 fe ff ff e8 24 04 ed ff e9 
RIP: mark_buffer_dirty_inode+0x2d8/0x3a0 fs/buffer.c:605 RSP: ffff88805b4c73b8
---[ end trace 990a7f4dae1ca5cb ]---