FAT-fs (loop5): Can't find a valid FAT filesystem
sg_write: data in/out 100/251 bytes for SCSI command 0x0-- guessing data in;
   program syz-executor.6 not setting count and/or reply_len properly
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WARNING: CPU: 0 PID: 15033 at lib/iov_iter.c:644 _copy_from_iter+0x2f1/0x1320
Modules linked in:
CPU: 0 PID: 15033 Comm: syz-executor.6 Not tainted 6.4.0-rc1-next-20230511 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:_copy_from_iter+0x2f1/0x1320
Code: 92 ff ff 89 c3 e9 1f ff ff ff e8 fa 0b 36 ff be 88 02 00 00 48 c7 c7 e0 d4 9e 84 e8 49 16 5a ff e9 13 fe ff ff e8 df 0b 36 ff <0f> 0b 45 31 f6 e9 67 ff ff ff e8 d0 0b 36 ff 31 ff 89 ee e8 07 07
RSP: 0018:ffff888016bf7608 EFLAGS: 00010212
RAX: 0000000000000e11 RBX: 0000000000000000 RCX: ffffc90006204000
RDX: 0000000000040000 RSI: ffffffff8215dfc1 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 00000000000000fb
R13: ffffea0001134a00 R14: 00000000000000fb R15: ffff888016bf7838
FS:  00007fcdf64fa700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2c521000 CR3: 000000000db9c000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 copy_page_from_iter+0xe3/0x180
 blk_rq_map_user_iov+0xb39/0x16c0
 blk_rq_map_user_io+0x1d1/0x200
 sg_common_write.constprop.0+0xd8d/0x15f0
 sg_write.part.0+0x698/0xac0
 sg_write+0x8d/0xe0
 vfs_write+0x2b8/0xd40
 ksys_write+0x12b/0x260
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7fcdf8f84b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcdf64fa188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fcdf9097f60 RCX: 00007fcdf8f84b19
RDX: 0000000000000125 RSI: 0000000020000200 RDI: 0000000000000003
RBP: 00007fcdf8fdef6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffd839a2df R14: 00007fcdf64fa300 R15: 0000000000022000
 </TASK>
irq event stamp: 1733
hardirqs last  enabled at (1745): [<ffffffff812fd068>] __up_console_sem+0x78/0x80
hardirqs last disabled at (1754): [<ffffffff812fd04d>] __up_console_sem+0x5d/0x80
softirqs last  enabled at (1062): [<ffffffff8118cf1c>] __irq_exit_rcu+0xcc/0x110
softirqs last disabled at (997): [<ffffffff8118cf1c>] __irq_exit_rcu+0xcc/0x110
---[ end trace 0000000000000000 ]---