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kernel BUG at fs/buffer.c:605!
audit: type=1804 audit(1588066694.124:14264): pid=30074 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir189531752/syzkaller.ecrPAC/465/file0/file0" dev="loop5" ino=386 res=1
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 30093 Comm: syz-executor.5 Not tainted 4.14.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880a97e6500 task.stack: ffff88804bd90000
RIP: 0010:mark_buffer_dirty_inode fs/buffer.c:605 [inline]
RIP: 0010:mark_buffer_dirty_inode+0x2d8/0x3a0 fs/buffer.c:596
RSP: 0018:ffff88804bd97710 EFLAGS: 00010212
RAX: 0000000000040000 RBX: ffff8880281ccbd0 RCX: ffffc9000710b000
RDX: 000000000000756f RSI: ffffffff8196cb58 RDI: ffff88802667b480
RBP: ffff88802667b320 R08: 0000000000000001 R09: 0000000000000004
R10: ffff8880a97e6e28 R11: ffff8880a97e6500 R12: ffff8880a69684e8
R13: 0000000000000000 R14: ffff888021824240 R15: ffff88804bd977e0
FS:  00007f21e1066700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005636d290e6a8 CR3: 0000000097df8000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat_free_clusters+0x2fc/0x750 fs/fat/fatent.c:596
 fat_free fs/fat/file.c:351 [inline]
 fat_truncate_blocks+0x69f/0xb10 fs/fat/file.c:369
 fat_setattr+0x6b9/0xad0 fs/fat/file.c:513
 notify_change+0x8d1/0xd10 fs/attr.c:313
 do_truncate+0xff/0x1a0 fs/open.c:63
 handle_truncate fs/namei.c:3010 [inline]
 do_last fs/namei.c:3437 [inline]
 path_openat+0x25e4/0x3c50 fs/namei.c:3569
 do_filp_open+0x18e/0x250 fs/namei.c:3603
 do_sys_open+0x29d/0x3f0 fs/open.c:1081
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c829
RSP: 002b:00007f21e1065c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00000000004db140 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000240
RBP: 000000000078c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000009a R14: 00000000004c3307 R15: 00007f21e10666d4
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 f5 a9 04 e9 20 fe ff ff e8 a8 7a c3 ff <0f> 0b 4c 89 ff e8 fe cd ec ff e9 05 fe ff ff e8 f4 cd ec ff e9 
RIP: mark_buffer_dirty_inode fs/buffer.c:605 [inline] RSP: ffff88804bd97710
RIP: mark_buffer_dirty_inode+0x2d8/0x3a0 fs/buffer.c:596 RSP: ffff88804bd97710
---[ end trace 300c434c6570fde5 ]---