CVE-2023-52866

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: ? 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 Modules linked in: Dumping ftrace buffer: (ftrace buffer empty) —[ end trace 0000000000000000 ]— 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: —truncated—

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Potential Mitigations

• Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
• When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
• Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
• To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/540.html

References

• https://git.kernel.org/stable/c/64da1f6147dac7f8499d4937a0d7ea990bf569e8
• https://git.kernel.org/stable/c/6c8f953728d75104d994893f58801c457274335a
• https://git.kernel.org/stable/c/91cfe0bbaa1c434d4271eb6e1d7aaa1fe8d121f6
• https://git.kernel.org/stable/c/64da1f6147dac7f8499d4937a0d7ea990bf569e8
• https://git.kernel.org/stable/c/6c8f953728d75104d994893f58801c457274335a
• https://git.kernel.org/stable/c/91cfe0bbaa1c434d4271eb6e1d7aaa1fe8d121f6