KMSAN: uninit-value in joydev_connect

syzbot
2020-08-11T17:06:35Z

Hello,

syzbot found the following issue on:

HEAD commit: ce8056d1 wip: changed copy_from_user where instrumented
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=14b5da2c900000
kernel config: https://syzkaller.appspot.com/x/.config?x=3afe005fb99591f
dashboard link: https://syzkaller.appspot.com/bug?extid=6a1bb5a33a0b128085bc
compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6a1bb5a33a0b128085bc@syzkaller.appspotmail.com

gtco 4-1:0.219: Collection level already at zero
gtco 4-1:0.219: Not enough data (need 130, have 129)
input: GTCO_CalComp as /devices/platform/dummy_hcd.3/usb4/4-1/4-1:0.219/input/input5
=====================================================
BUG: KMSAN: uninit-value in joydev_connect+0x10c0/0x1920 drivers/input/joydev.c:958
CPU: 1 PID: 8715 Comm: kworker/1:3 Not tainted 5.8.0-rc5-syzkaller #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+0x21c/0x280 lib/dump_stack.c:118
kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
__msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
joydev_connect+0x10c0/0x1920 drivers/input/joydev.c:958
input_attach_handler drivers/input/input.c:1031 [inline]
input_register_device+0x1d7b/0x21c0 drivers/input/input.c:2229
gtco_probe+0x32ce/0x39b0 drivers/input/tablet/gtco.c:990
usb_probe_interface+0xece/0x1550 drivers/usb/core/driver.c:374
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_set_configuration+0x380f/0x3f10 drivers/usb/core/message.c:2032
usb_generic_driver_probe+0x138/0x300 drivers/usb/core/generic.c:241
usb_probe_device+0x311/0x490 drivers/usb/core/driver.c:272
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_new_device+0x1bd4/0x2a30 drivers/usb/core/hub.c:2554
hub_port_connect drivers/usb/core/hub.c:5208 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x5e7b/0x8a70 drivers/usb/core/hub.c:5576
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Uninit was stored to memory at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
__msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
input_set_abs_params+0x331/0x540 drivers/input/input.c:514
gtco_setup_caps drivers/input/tablet/gtco.c:598 [inline]
gtco_probe+0x2800/0x39b0 drivers/input/tablet/gtco.c:966
usb_probe_interface+0xece/0x1550 drivers/usb/core/driver.c:374
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_set_configuration+0x380f/0x3f10 drivers/usb/core/message.c:2032
usb_generic_driver_probe+0x138/0x300 drivers/usb/core/generic.c:241
usb_probe_device+0x311/0x490 drivers/usb/core/driver.c:272
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_new_device+0x1bd4/0x2a30 drivers/usb/core/hub.c:2554
hub_port_connect drivers/usb/core/hub.c:5208 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x5e7b/0x8a70 drivers/usb/core/hub.c:5576
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Uninit was stored to memory at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
__msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
parse_hid_report_descriptor drivers/input/tablet/gtco.c:330 [inline]
gtco_probe+0x1e56/0x39b0 drivers/input/tablet/gtco.c:935
usb_probe_interface+0xece/0x1550 drivers/usb/core/driver.c:374
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_set_configuration+0x380f/0x3f10 drivers/usb/core/message.c:2032
usb_generic_driver_probe+0x138/0x300 drivers/usb/core/generic.c:241
usb_probe_device+0x311/0x490 drivers/usb/core/driver.c:272
really_probe+0xf20/0x20b0 drivers/base/dd.c:529
driver_probe_device+0x293/0x390 drivers/base/dd.c:701
__device_attach_driver+0x63f/0x830 drivers/base/dd.c:807
bus_for_each_drv+0x2ca/0x3f0 drivers/base/bus.c:431
__device_attach+0x4e2/0x7f0 drivers/base/dd.c:873
device_initial_probe+0x4a/0x60 drivers/base/dd.c:920
bus_probe_device+0x177/0x3d0 drivers/base/bus.c:491
device_add+0x3b0e/0x40d0 drivers/base/core.c:2680
usb_new_device+0x1bd4/0x2a30 drivers/usb/core/hub.c:2554
hub_port_connect drivers/usb/core/hub.c:5208 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5348 [inline]
port_event drivers/usb/core/hub.c:5494 [inline]
hub_event+0x5e7b/0x8a70 drivers/usb/core/hub.c:5576
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Local variable ----globalval.i@gtco_probe created at:
parse_hid_report_descriptor drivers/input/tablet/gtco.c:221 [inline]
gtco_probe+0xda0/0x39b0 drivers/input/tablet/gtco.c:935
parse_hid_report_descriptor drivers/input/tablet/gtco.c:221 [inline]
gtco_probe+0xda0/0x39b0 drivers/input/tablet/gtco.c:935
=====================================================

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