KMSAN: uninit-value in rt2500usb_probe_hw

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: cebbfdbc kmsan: merge set_no_shadow_page() and set_no_orig..
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=1125cb59600000
kernel config: https://syzkaller.appspot.com/x/.config?x=f03c659d0830ab8d
dashboard link: https://syzkaller.appspot.com/bug?extid=35c80b2190255a410f66
compiler: clang version 9.0.0 (/home/glider/llvm/clang
80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=146abd21600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=106a19b5600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+35c80b...@syzkaller.appspotmail.com

usb 1-1: config 0 descriptor??
usb 1-1: reset high-speed USB device number 2 using dummy_hcd
usb 1-1: device descriptor read/64, error -71
usb 1-1: Using ep0 maxpacket: 16
ieee80211 phy3: rt2x00usb_vendor_request: Error - Vendor Request 0x09
failed for offset 0x0000 with error -71
ieee80211 phy3: rt2x00_set_chip: Info - Chipset detected - rt: 2570, rf:
0000, rev: 8771
==================================================================
BUG: KMSAN: uninit-value in rt2500usb_init_eeprom
drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1443 [inline]
BUG: KMSAN: uninit-value in rt2500usb_probe_hw+0xb5e/0x22a0
drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1757
CPU: 0 PID: 3369 Comm: kworker/0:2 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x191/0x1f0 lib/dump_stack.c:113
kmsan_report+0x162/0x2d0 mm/kmsan/kmsan_report.c:109
__msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294
rt2500usb_init_eeprom drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1443
[inline]
rt2500usb_probe_hw+0xb5e/0x22a0
drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1757
rt2x00lib_probe_dev+0xba9/0x3260
drivers/net/wireless/ralink/rt2x00/rt2x00dev.c:1427
rt2x00usb_probe+0x7ae/0xf60
drivers/net/wireless/ralink/rt2x00/rt2x00usb.c:842
rt2500usb_probe+0x50/0x60
drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1966
usb_probe_interface+0xd19/0x1310 drivers/usb/core/driver.c:361
really_probe+0x1373/0x1dc0 drivers/base/dd.c:552
driver_probe_device+0x1ba/0x510 drivers/base/dd.c:709
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:816
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x489/0x750 drivers/base/dd.c:882
device_initial_probe+0x4a/0x60 drivers/base/dd.c:929
bus_probe_device+0x131/0x390 drivers/base/bus.c:514
device_add+0x25b5/0x2df0 drivers/base/core.c:2165
usb_set_configuration+0x309f/0x3710 drivers/usb/core/message.c:2027
generic_probe+0xe7/0x280 drivers/usb/core/generic.c:210
usb_probe_device+0x146/0x200 drivers/usb/core/driver.c:266
really_probe+0x1373/0x1dc0 drivers/base/dd.c:552
driver_probe_device+0x1ba/0x510 drivers/base/dd.c:709
__device_attach_driver+0x5b8/0x790 drivers/base/dd.c:816
bus_for_each_drv+0x28e/0x3b0 drivers/base/bus.c:454
__device_attach+0x489/0x750 drivers/base/dd.c:882
device_initial_probe+0x4a/0x60 drivers/base/dd.c:929
bus_probe_device+0x131/0x390 drivers/base/bus.c:514
device_add+0x25b5/0x2df0 drivers/base/core.c:2165
usb_new_device+0x23e5/0x2fb0 drivers/usb/core/hub.c:2536
hub_port_connect drivers/usb/core/hub.c:5098 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
port_event drivers/usb/core/hub.c:5359 [inline]
hub_event+0x581d/0x72f0 drivers/usb/core/hub.c:5441
process_one_work+0x1572/0x1ef0 kernel/workqueue.c:2269
worker_thread+0x111b/0x2460 kernel/workqueue.c:2415
kthread+0x4b5/0x4f0 kernel/kthread.c:256
ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Local variable description: ----reg.i.i@rt2500usb_probe_hw
Variable was created at:
rt2500usb_register_read drivers/net/wireless/ralink/rt2x00/rt2500usb.c:51
[inline]
rt2500usb_init_eeprom drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1440
[inline]
rt2500usb_probe_hw+0x774/0x22a0
drivers/net/wireless/ralink/rt2x00/rt2500usb.c:1757
rt2x00lib_probe_dev+0xba9/0x3260
drivers/net/wireless/ralink/rt2x00/rt2x00dev.c:1427
==================================================================


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