TLDRVuln - Cybersecurity Vulnerabilities Made Simple

In the Linux kernel, the following vulnerability has been resolved:

HID: uclogic: Fix user-memory-access bug in uclogic_params_ugee_v2_init_event_hooks()

When CONFIG_HID_UCLOGIC=y and CONFIG_KUNIT_ALL_TESTS=y, launch kernel and

then the below user-memory-access bug occurs.

In hid_test_uclogic_params_cleanup_event_hooks(),it call

uclogic_params_ugee_v2_init_event_hooks() with the first arg=NULL, so

when it calls uclogic_params_ugee_v2_has_battery(), the hid_get_drvdata()

will access hdev->dev with hdev=NULL, which will cause below

user-memory-access.

So add a fake_device with quirks member and call hid_set_drvdata()

to assign hdev->dev->driver_data which avoids the null-ptr-def bug

for drvdata->quirks in uclogic_params_ugee_v2_has_battery(). After applying

this patch, the below user-memory-access bug never occurs.

general protection fault, probably for non-canonical address 0xdffffc0000000329: 0000 [#1] PREEMPT SMP KASAN

KASAN: probably user-memory-access in range [0x0000000000001948-0x000000000000194f]

CPU: 5 PID: 2189 Comm: kunit_try_catch Tainted: G B W N 6.6.0-rc2+ #30

Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014

RIP: 0010:uclogic_params_ugee_v2_init_event_hooks+0x87/0x600

Code: f3 f3 65 48 8b 14 25 28 00 00 00 48 89 54 24 60 31 d2 48 89 fa c7 44 24 30 00 00 00 00 48 c7 44 24 28 02 f8 02 01 48 c1 ea 03 <80> 3c 02 00 0f 85 2c 04 00 00 48 8b 9d 48 19 00 00 48 b8 00 00 00

RSP: 0000:ffff88810679fc88 EFLAGS: 00010202

RAX: dffffc0000000000 RBX: 0000000000000004 RCX: 0000000000000000

RDX: 0000000000000329 RSI: ffff88810679fd88 RDI: 0000000000001948

RBP: 0000000000000000 R08: 0000000000000000 R09: ffffed1020f639f0

R10: ffff888107b1cf87 R11: 0000000000000400 R12: 1ffff11020cf3f92

R13: ffff88810679fd88 R14: ffff888100b97b08 R15: ffff8881030bb080

FS: 0000000000000000(0000) GS:ffff888119e80000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000000000000000 CR3: 0000000005286001 CR4: 0000000000770ee0

DR0: ffffffff8fdd6cf4 DR1: ffffffff8fdd6cf5 DR2: ffffffff8fdd6cf6

DR3: ffffffff8fdd6cf7 DR6: 00000000fffe0ff0 DR7: 0000000000000600

PKRU: 55555554

Call Trace:

<TASK>

? die_addr+0x3d/0xa0

? exc_general_protection+0x144/0x220

? asm_exc_general_protection+0x22/0x30

? uclogic_params_ugee_v2_init_event_hooks+0x87/0x600

? sched_clock_cpu+0x69/0x550

? uclogic_parse_ugee_v2_desc_gen_params+0x70/0x70

? load_balance+0x2950/0x2950

? rcu_trc_cmpxchg_need_qs+0x67/0xa0

hid_test_uclogic_params_cleanup_event_hooks+0x9e/0x1a0

? uclogic_params_ugee_v2_init_event_hooks+0x600/0x600

? __switch_to+0x5cf/0xe60

? migrate_enable+0x260/0x260

? __kthread_parkme+0x83/0x150

? kunit_try_run_case_cleanup+0xe0/0xe0

kunit_generic_run_threadfn_adapter+0x4a/0x90

? kunit_try_catch_throw+0x80/0x80

kthread+0x2b5/0x380

? kthread_complete_and_exit+0x20/0x20

ret_from_fork+0x2d/0x70

? kthread_complete_and_exit+0x20/0x20

ret_from_fork_asm+0x11/0x20

</TASK>

Modules linked in:

Dumping ftrace buffer:

(ftrace buffer empty)

---[ end trace 0000000000000000 ]---