------------[ cut here ]------------
kernel BUG at fs/buffer.c:553!
audit: type=1804 audit(1592740340.808:144): pid=3179 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir852246738/syzkaller.HkQseq/851/file0/file0" dev="loop4" ino=225 res=1
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3131 Comm: syz-executor.4 Not tainted 4.19.128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mark_buffer_dirty_inode+0x2f8/0x3c0 fs/buffer.c:553
Code: 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 b2 98 69 05 e9 00 fe ff ff e8 88 23 b3 ff <0f> 0b 4c 89 ff e8 0e b1 e8 ff e9 e5 fd ff ff e8 04 b1 e8 ff e9 6e
RSP: 0018:ffff88821b1b7ae8 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88802fa06348 RCX: ffffc90012d14000
RDX: 0000000000040000 RSI: ffffffff81b47738 RDI: ffff888040001ef8
RBP: ffff888040001d98 R08: 0000000000000000 R09: 0000000000000003
R10: ffffed1015cc473a R11: ffff8880ae6239d3 R12: ffff88808388cb60
R13: 0000000000000000 R14: ffff88821b1b7c48 R15: ffff888043c51200
FS:  00007fdb8f12f700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f380d5d0270 CR3: 0000000218f10000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat_alloc_clusters+0x5d6/0xed0 fs/fat/fatent.c:503
 fat_add_cluster+0x6d/0xf0 fs/fat/inode.c:101
 fat_fallocate+0x26d/0x310 fs/fat/file.c:300
 vfs_fallocate+0x484/0x990 fs/open.c:308
 ksys_fallocate+0x51/0x90 fs/open.c:331
 __do_sys_fallocate fs/open.c:339 [inline]
 __se_sys_fallocate fs/open.c:337 [inline]
 __x64_sys_fallocate+0x93/0xf0 fs/open.c:337
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45ca59
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdb8f12ec78 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00000000004dbf60 RCX: 000000000045ca59
RDX: 0000000000000000 RSI: 0000000100000001 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 000000002811ffff R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000b3 R14: 00000000004c3676 R15: 00007fdb8f12f6d4
Modules linked in:
---[ end trace 6053186c7bdbe8e0 ]---
RIP: 0010:mark_buffer_dirty_inode+0x2f8/0x3c0 fs/buffer.c:553
Code: 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 b2 98 69 05 e9 00 fe ff ff e8 88 23 b3 ff <0f> 0b 4c 89 ff e8 0e b1 e8 ff e9 e5 fd ff ff e8 04 b1 e8 ff e9 6e
RSP: 0018:ffff88821b1b7ae8 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88802fa06348 RCX: ffffc90012d14000
RDX: 0000000000040000 RSI: ffffffff81b47738 RDI: ffff888040001ef8
RBP: ffff888040001d98 R08: 0000000000000000 R09: 0000000000000003
R10: ffffed1015cc473a R11: ffff8880ae6239d3 R12: ffff88808388cb60
R13: 0000000000000000 R14: ffff88821b1b7c48 R15: ffff888043c51200
FS:  00007fdb8f12f700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ff84671f78 CR3: 0000000218f10000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400