usb 4-1: Rio opened.
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BUG: KMSAN: uninit-value in __vfs_read+0x1a9/0xc90 fs/read_write.c:425
CPU: 0 PID: 13486 Comm: syz-executor.3 Not tainted 5.4.0-rc2+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x153/0x2c0 mm/kmsan/kmsan_report.c:113
 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:250
 read_rio+0x55d/0x860 drivers/usb/misc/rio500.c:398
 __vfs_read+0x1a9/0xc90 fs/read_write.c:425
 vfs_read+0x359/0x6f0 fs/read_write.c:461
 ksys_read+0x265/0x430 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read+0x92/0xb0 fs/read_write.c:595
 __x64_sys_read+0x4a/0x70 fs/read_write.c:595
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x459a59
Code: fd 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3232832c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 00000000000000ee RSI: 0000000020000140 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f32328336d4
R13: 00000000004c70d5 R14: 00000000004dc948 R15: 00000000ffffffff

Local variable description: ----partial@read_rio
Variable was created at:
 read_rio+0xff/0x860 drivers/usb/misc/rio500.c:354
 __vfs_read+0x1a9/0xc90 fs/read_write.c:425
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