------------[ cut here ]------------
kernel BUG at fs/buffer.c:553!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8468 Comm: syz-executor.0 Not tainted 4.19.118-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mark_buffer_dirty_inode fs/buffer.c:553 [inline]
RIP: 0010:mark_buffer_dirty_inode+0x2f8/0x3c0 fs/buffer.c:544
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 c2 8d 6b 05 e9 00 fe ff ff e8 f8 34 b3 ff <0f> 0b 4c 89 ff e8 de 05 e9 ff e9 e5 fd ff ff e8 d4 05 e9 ff e9 6e
RSP: 0018:ffff88803414f308 EFLAGS: 00010206
RAX: 0000000000040000 RBX: ffff888043847888 RCX: ffffc90005aa4000
RDX: 000000000001f2a0 RSI: ffffffff81b474a8 RDI: ffff888080252478
RBP: ffff888080252318 R08: 0000000000000000 R09: 0000000000000003
R10: ffffed1015cc4732 R11: ffff8880ae623993 R12: ffff8880802436e0
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88803414f4a0
FS:  00007f9be02b5700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000010d3978 CR3: 00000000a0af5000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fat12_ent_put+0x18c/0x3a0 fs/fat/fatent.c:171
 fat_alloc_clusters+0x5d0/0xe50 fs/fat/fatent.c:503
 fat_add_cluster+0x6d/0xf0 fs/fat/inode.c:101
 __fat_get_block fs/fat/inode.c:148 [inline]
 fat_get_block+0x2fb/0x8e0 fs/fat/inode.c:183
 __block_write_begin_int+0x480/0x17a0 fs/buffer.c:1978
 __block_write_begin fs/buffer.c:2028 [inline]
 block_write_begin+0x58/0x2e0 fs/buffer.c:2087
 cont_write_begin+0x46f/0x7e0 fs/buffer.c:2440
 fat_write_begin+0x8d/0x120 fs/fat/inode.c:229
 cont_expand_zero fs/buffer.c:2367 [inline]
 cont_write_begin+0x211/0x7e0 fs/buffer.c:2430
 fat_write_begin+0x8d/0x120 fs/fat/inode.c:229
 generic_cont_expand_simple+0x106/0x170 fs/buffer.c:2331
 fat_cont_expand+0x71/0x2b0 fs/fat/file.c:231
 fat_setattr+0xa17/0xc60 fs/fat/file.c:510
 notify_change+0xad7/0xfb0 fs/attr.c:334
 do_truncate+0x134/0x1f0 fs/open.c:63
 do_sys_ftruncate+0x499/0x560 fs/open.c:194
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c829
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:00007f9be02b4c78 EFLAGS: 00000246 ORIG_RAX: 000000000000004d
RAX: ffffffffffffffda RBX: 00000000004dc500 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000000048280 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000e9 R14: 00000000004c3701 R15: 00007f9be02b56d4
Modules linked in:
---[ end trace f8f0cd75ba003bc5 ]---
RIP: 0010:mark_buffer_dirty_inode fs/buffer.c:553 [inline]
RIP: 0010:mark_buffer_dirty_inode+0x2f8/0x3c0 fs/buffer.c:544
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 c2 8d 6b 05 e9 00 fe ff ff e8 f8 34 b3 ff <0f> 0b 4c 89 ff e8 de 05 e9 ff e9 e5 fd ff ff e8 d4 05 e9 ff e9 6e
RSP: 0018:ffff88803414f308 EFLAGS: 00010206
RAX: 0000000000040000 RBX: ffff888043847888 RCX: ffffc90005aa4000
RDX: 000000000001f2a0 RSI: ffffffff81b474a8 RDI: ffff888080252478
RBP: ffff888080252318 R08: 0000000000000000 R09: 0000000000000003
R10: ffffed1015cc4732 R11: ffff8880ae623993 R12: ffff8880802436e0
R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88803414f4a0
FS:  00007f9be02b5700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b7538adb8 CR3: 00000000a0af5000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400