audit: type=1400 audit(1566229809.801:42): avc:  denied  { module_load } for  pid=6938 comm="syz-executor.1" path=2F6D656D66643A747275736F76657285896136B3F143096C619A2E6F566171202864656C6574656429 dev="tmpfs" ino=26515 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:tmpfs_t:s0 tclass=system permissive=1
IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready
8021q: adding VLAN 0 to HW filter on device batadv0
audit: type=1804 audit(1566229810.031:43): pid=6955 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.3" name="/root/syzkaller-testdir308129357/syzkaller.L2h2gH/7/file0/file0" dev="loop3" ino=3 res=1
------------[ cut here ]------------
kernel BUG at fs/buffer.c:605!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 6955 Comm: syz-executor.3 Not tainted 4.14.139 #35
kobject: 'loop3' (ffff8880a49cb7a0): kobject_uevent_env
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'loop3' (ffff8880a49cb7a0): fill_kobj_path: path = '/devices/virtual/block/loop3'
task: ffff888057242440 task.stack: ffff888057208000
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:ffff88805720f678 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff8880946319d8 RCX: ffffc9000603e000
RDX: 0000000000040000 RSI: ffffffff819964ca RDI: ffff888094579ef8
RBP: ffff88805720f6b0 R08: ffff888057242440 R09: 0000000000000004
R10: 0000000000000000 R11: ffff888057242440 R12: ffff888094579d98
R13: 0000000000000000 R14: ffff8880889e9be0 R15: 00000000000038fb
FS:  00007f564e549700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f564e527db8 CR3: 00000000957a2000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
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: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:00007f564e548c78 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: 00007f564e5496d4
R13: 00000000004bfe84 R14: 00000000004d1d40 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 10 9d 82 04 e9 13 fe ff ff e8 a6 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: ffff88805720f678
RIP: mark_buffer_dirty_inode+0x2ea/0x3e0 fs/buffer.c:596 RSP: ffff88805720f678
---[ end trace 915dad1e28692825 ]---