syzbot

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kernel BUG at fs/fat/inode.c:161!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 7987 Comm: syz-executor366 Not tainted 4.14.300-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
task: ffff8880a5ab6000 task.stack: ffff8880b3ff0000
RIP: 0010:__fat_get_block fs/fat/inode.c:161 [inline]
RIP: 0010:fat_get_block+0x647/0x750 fs/fat/inode.c:176
RSP: 0018:ffff8880b3ff76d8 EFLAGS: 00010297
RAX: ffff8880a5ab6000 RBX: ffff88808df1ae70 RCX: ffff8880b3ff7750
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88808df19ae8
RBP: ffff88808df19ba0 R08: ffff8880b3ff7770 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880a5ab6000 R12: ffff888095a9ccc0
R13: 0000000000000000 R14: 000000000000000b R15: 0000000000000001
FS:  0000555556497300(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f333ddc05a0 CR3: 000000009991e000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __block_write_begin_int+0x35c/0x11d0 fs/buffer.c:2038
 __block_write_begin fs/buffer.c:2088 [inline]
 block_write_begin+0x58/0x270 fs/buffer.c:2147
 cont_write_begin+0x4a3/0x740 fs/buffer.c:2497
 fat_write_begin+0x89/0x170 fs/fat/inode.c:222
 cont_expand_zero fs/buffer.c:2424 [inline]
 cont_write_begin+0x296/0x740 fs/buffer.c:2487
 fat_write_begin+0x89/0x170 fs/fat/inode.c:222
 generic_cont_expand_simple+0xe1/0x130 fs/buffer.c:2388
 fat_cont_expand+0x71/0x280 fs/fat/file.c:198
 fat_setattr+0x8b8/0xbe0 fs/fat/file.c:477
 notify_change+0x56b/0xd10 fs/attr.c:315
 do_truncate+0xff/0x1a0 fs/open.c:63
 vfs_truncate+0x456/0x680 fs/open.c:120
 do_sys_truncate.part.0+0xdc/0xf0 fs/open.c:143
 do_sys_truncate fs/open.c:137 [inline]
 SYSC_truncate fs/open.c:155 [inline]
 SyS_truncate+0x23/0x40 fs/open.c:153
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
Code: 17 af ff e9 bd fa ff ff 48 8b 7c 24 20 e8 f2 16 af ff e9 f4 fb ff ff 48 8b 7c 24 38 e8 f3 15 af ff e9 52 fe ff ff e8 f9 59 85 ff <0f> 0b e8 f2 59 85 ff 0f 0b e8 ab 17 af ff e9 b1 fa ff ff 48 8b 
RIP: __fat_get_block fs/fat/inode.c:161 [inline] RSP: ffff8880b3ff76d8
RIP: fat_get_block+0x647/0x750 fs/fat/inode.c:176 RSP: ffff8880b3ff76d8
---[ end trace fb004ccdcae2d1ee ]---