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kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 13315 Comm: syz-executor.0 Not tainted 4.14.126 #20
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'loop4' (ffff8880a4a3aa60): kobject_uevent_env
task: ffff88805e4483c0 task.stack: ffff88808bc28000
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:ffff88808bc2f3f0 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88807fc129d8 RCX: ffffc90005b77000
RDX: 0000000000040000 RSI: ffffffff8199212a RDI: ffff8880552d0ef8
RBP: ffff88808bc2f428 R08: ffff88805e4483c0 R09: 0000000000000004
R10: 0000000000000000 R11: ffff88805e4483c0 R12: ffff8880552d0d98
R13: 0000000000000000 R14: ffff88808decd3e0 R15: ffff88808bc2f6a8
FS:  00007fbb6572c700(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e77a0 CR3: 0000000098365000 CR4: 00000000001426f0
DR0: 0000000000000401 DR1: 0000000000000404 DR2: 0000000000000007
DR3: 0000000000000007 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat16_ent_put+0xc5/0x100 fs/fat/fatent.c:181
 fat_alloc_clusters+0x5a4/0xdb0 fs/fat/fatent.c:499
 fat_add_cluster+0x60/0xc0 fs/fat/inode.c:100
kobject: 'loop4' (ffff8880a4a3aa60): fill_kobj_path: path = '/devices/virtual/block/loop4'
 __fat_get_block fs/fat/inode.c:147 [inline]
 fat_get_block+0x2d4/0x7e0 fs/fat/inode.c:176
kobject: 'loop4' (ffff8880a4a3aa60): kobject_uevent_env
 __block_write_begin_int+0x396/0x1100 fs/buffer.c:2027
kobject: 'loop4' (ffff8880a4a3aa60): fill_kobj_path: path = '/devices/virtual/block/loop4'
 __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
 generic_perform_write+0x1f8/0x480 mm/filemap.c:3024
 __generic_file_write_iter+0x447/0x5b0 mm/filemap.c:3117
 generic_file_write_iter+0x303/0x660 mm/filemap.c:3177
 call_write_iter include/linux/fs.h:1777 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x4a7/0x6b0 fs/read_write.c:482
 vfs_write+0x198/0x500 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xfd/0x230 fs/read_write.c:582
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4592c9
RSP: 002b:00007fbb6572bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9
RDX: 0000000010fbb020 RSI: 0000000020000000 RDI: 0000000000000007
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbb6572c6d4
R13: 00000000004c9194 R14: 00000000004e0130 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 a0 2e 81 04 e9 13 fe ff ff e8 e6 86 c3 ff <0f> 0b 4c 89 ff e8 6c 27 ed ff e9 f8 fd ff ff e8 62 27 ed ff e9 
RIP: mark_buffer_dirty_inode fs/buffer.c:605 [inline] RSP: ffff88808bc2f3f0
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596 RSP: ffff88808bc2f3f0
---[ end trace beced8fdc18cd3d3 ]---
kobject: 'loop0' (ffff888097aaa1e0): kobject_uevent_env
FAT-fs (loop4): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1)
getblk(): invalid block size 512 requested