audit: type=1804 audit(1564712610.861:290): pid=20522 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="invalid_pcr" cause="ToMToU" comm="syz-executor.4" name="/root/syzkaller-testdir935695956/syzkaller.78pFCq/303/file0/file0" dev="loop4" ino=958 res=1
------------[ cut here ]------------
kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
kobject: 'loop2' (ffff8880a4a71260): kobject_uevent_env
Modules linked in:
CPU: 1 PID: 20522 Comm: syz-executor.4 Not tainted 4.14.135 #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88805e5f0180 task.stack: ffff888060938000
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:ffff88806093f678 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88809a2c4dc8 RCX: ffffc9000d267000
RDX: 0000000000040000 RSI: ffffffff81994b7a RDI: ffff888065259ef8
RBP: ffff88806093f6b0 R08: ffff88805e5f0180 R09: 0000000000000004
R10: 0000000000000000 R11: ffff88805e5f0180 R12: ffff888065259d98
R13: 0000000000000000 R14: ffff8880a77c14a0 R15: 00000000000025f6
FS:  00007fa6242dd700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000001a833a8 CR3: 000000009c36e000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kobject: 'loop2' (ffff8880a4a71260): fill_kobj_path: path = '/devices/virtual/block/loop2'
 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:1084
 SYSC_open fs/open.c:1102 [inline]
 SyS_open fs/open.c:1097 [inline]
 SYSC_creat fs/open.c:1142 [inline]
 SyS_creat+0x27/0x30 fs/open.c:1140
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459829
RSP: 002b:00007fa6242dcc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459829
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6242dd6d4
R13: 00000000004bfe84 R14: 00000000004d1c80 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 70 90 82 04 e9 13 fe ff ff e8 e6 78 c3 ff <0f> 0b 4c 89 ff e8 5c 25 ed ff e9 f8 fd ff ff e8 52 25 ed ff e9 
RIP: mark_buffer_dirty_inode fs/buffer.c:605 [inline] RSP: ffff88806093f678
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596 RSP: ffff88806093f678
---[ end trace 2cc3bc93d595256d ]---