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kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 18924 Comm: syz-executor.0 Not tainted 4.14.130 #24
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88808003c640 task.stack: ffff8880859d0000
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:ffff8880859d7a40 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88809540a7e0 RCX: ffffc90005e45000
RDX: 0000000000040000 RSI: ffffffff8199227a RDI: ffff88807d86a478
RBP: ffff8880859d7a78 R08: ffff88808003c640 R09: 0000000000000002
R10: 0000000000000000 R11: ffff88808003c640 R12: ffff88807d86a318
R13: 0000000000000000 R14: ffff88807d87ba20 R15: ffff88805d42e8c0
FS:  00007f5f0d398700(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000c37058 CR3: 00000000a8ed5000 CR4: 00000000001426f0
Call Trace:
 fat_mirror_bhs+0x256/0x410 fs/fat/fatent.c:394
 fat_alloc_clusters+0xb28/0xdb0 fs/fat/fatent.c:539
 fat_add_cluster+0x60/0xc0 fs/fat/inode.c:100
 fat_fallocate+0x249/0x2e0 fs/fat/file.c:267
 vfs_fallocate+0x34f/0x7a0 fs/open.c:319
 SYSC_fallocate fs/open.c:342 [inline]
 SyS_fallocate+0x52/0x90 fs/open.c:336
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459519
RSP: 002b:00007f5f0d397c78 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459519
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000369e5d84 R11: 0000000000000246 R12: 00007f5f0d3986d4
R13: 00000000004bfbf4 R14: 00000000004d1820 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 51 81 04 e9 13 fe ff ff e8 06 85 c3 ff <0f> 0b 4c 89 ff e8 ac 26 ed ff e9 f8 fd ff ff e8 a2 26 ed ff e9 
RIP: mark_buffer_dirty_inode fs/buffer.c:605 [inline] RSP: ffff8880859d7a40
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596 RSP: ffff8880859d7a40
kobject: 'loop2' (ffff8880a4a211e0): kobject_uevent_env
kobject: 'loop2' (ffff8880a4a211e0): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop4' (ffff8880a4a901a0): kobject_uevent_env
kobject: 'loop3' (ffff8880a4a33260): kobject_uevent_env
kobject: 'loop4' (ffff8880a4a901a0): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (ffff8880a4a33260): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (ffff8880a4a901a0): kobject_uevent_env
kobject: 'loop1' (ffff8880a49b77e0): kobject_uevent_env
kobject: 'loop1' (ffff8880a49b77e0): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (ffff8880a4a901a0): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (ffff8880a49b77e0): kobject_uevent_env
FAT-fs (loop4): invalid media value (0x00)
kobject: 'loop1' (ffff8880a49b77e0): fill_kobj_path: path = '/devices/virtual/block/loop1'
FAT-fs (loop4): Can't find a valid FAT filesystem
device sit0 entered promiscuous mode
kobject: 'loop4' (ffff8880a4a901a0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4a901a0): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (ffff8880a49b77e0): kobject_uevent_env
kobject: 'loop1' (ffff8880a49b77e0): kobject_uevent_env
kobject: 'loop1' (ffff8880a49b77e0): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: '0:46' (ffff88805cde0c10): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: '0:46' (ffff88805cde0c10): kobject_uevent_env
kobject: 'loop4' (ffff8880a4a901a0): kobject_uevent_env
kobject: 'loop1' (ffff8880a49b77e0): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (ffff8880a4a901a0): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: '0:46' (ffff88805cde0c10): fill_kobj_path: path = '/devices/virtual/bdi/0:46'
FAT-fs (loop4): invalid media value (0x00)
FAT-fs (loop4): Can't find a valid FAT filesystem
kobject: 'loop0' (ffff888063bdae20): kobject_uevent_env
device sit0 left promiscuous mode
device sit0 entered promiscuous mode
kobject: 'loop0' (ffff888063bdae20): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: '0:48' (ffff88805bdaa5d0): kobject_add_internal: parent: 'bdi', set: 'devices'
kobject: 'loop1' (ffff8880a49b77e0): kobject_uevent_env
kobject: 'loop1' (ffff8880a49b77e0): fill_kobj_path: path = '/devices/virtual/block/loop1'
---[ end trace 2e1ac3a969997e26 ]---