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kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 8275 Comm: syz-executor.5 Not tainted 4.14.133 #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88805fdce4c0 task.stack: ffff88804fcd8000
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:ffff88804fcdf678 EFLAGS: 00010212
RAX: 0000000000040000 RBX: ffff8880741c0a80 RCX: ffffc9000b438000
RDX: 0000000000024fba RSI: ffffffff819921ca RDI: ffff8880741c1ef8
RBP: ffff88804fcdf6b0 R08: ffff88805fdce4c0 R09: 0000000000000004
R10: 0000000000000000 R11: ffff88805fdce4c0 R12: ffff8880741c1d98
R13: 0000000000000000 R14: ffff8880a77c34a0 R15: 000000000000097d
FS:  00007f0fdf1d7700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000625208 CR3: 0000000098cdc000 CR4: 00000000001426e0
Call Trace:
 fat16_ent_put+0xc5/0x100 /fs/fat/fatent.c:181
 fat_free_clusters+0x369/0x810 /fs/fat/fatent.c:593
 fat_free /fs/fat/file.c:351 [inline]
 fat_truncate_blocks+0x693/0xae0 /fs/fat/file.c:369
 fat_setattr+0x6c1/0xae0 /fs/fat/file.c:513
 notify_change+0x8d1/0xd10 /fs/attr.c:313
 do_truncate+0x124/0x1c0 /fs/open.c:63
 handle_truncate /fs/namei.c:3009 [inline]
 do_last /fs/namei.c:3434 [inline]
 path_openat+0x2786/0x3f70 /fs/namei.c:3566
 do_filp_open+0x18e/0x250 /fs/namei.c:3600
 do_sys_open+0x2c5/0x430 /fs/open.c:1065
 SYSC_open /fs/open.c:1083 [inline]
 SyS_open /fs/open.c:1078 [inline]
 SYSC_creat /fs/open.c:1123 [inline]
 SyS_creat+0x27/0x30 /fs/open.c:1121
 do_syscall_64+0x1e8/0x640 /arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459819
RSP: 002b:00007f0fdf1d6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0fdf1d76d4
R13: 00000000004bfe84 R14: 00000000004d1ae0 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 f0 8b 81 04 e9 13 fe ff ff e8 26 85 c3 ff <0f> 0b 4c 89 ff e8 dc 26 ed ff e9 f8 fd ff ff e8 d2 26 ed ff e9 
RIP: mark_buffer_dirty_inode /fs/buffer.c:605 [inline] RSP: ffff88804fcdf678
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 /fs/buffer.c:596 RSP: ffff88804fcdf678
kobject: 'loop1' (ffff8880a49ad720): kobject_uevent_env
---[ end trace a1062d0cc107d841 ]---
kobject: 'loop1' (ffff8880a49ad720): fill_kobj_path: path = '/devices/virtual/block/loop1'