CVE-2024-46693: soc: qcom: pmic_glink: Fix race during initialization

Description

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

soc: qcom: pmic_glink: Fix race during initialization

As pointed out by Stephen Boyd it is possible that during initialization
of the pmic_glink child drivers, the protection-domain notifiers fires,
and the associated work is scheduled, before the client registration
returns and as a result the local "client" pointer has been initialized.

The outcome of this is a NULL pointer dereference as the "client"
pointer is blindly dereferenced.

Timeline provided by Stephen:
CPU0 CPU1
---- ----
ucsi->client = NULL;
devm_pmic_glink_register_client()
client->pdr_notify(client->priv, pg->client_state)
pmic_glink_ucsi_pdr_notify()
schedule_work(&ucsi->register_work)

pmic_glink_ucsi_register()
ucsi_register()
pmic_glink_ucsi_read_version()
pmic_glink_ucsi_read()
pmic_glink_ucsi_read()
pmic_glink_send(ucsi->client)

ucsi->client = client // Too late!

This code is identical across the altmode, battery manager and usci
child drivers.

Resolve this by splitting the allocation of the "client" object and the
registration thereof into two operations.

This only happens if the pr...

Classification

CVE ID: CVE-2024-46693

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.03% (probability of being exploited)

EPSS Percentile: 7.2% (scored less or equal to compared to others)

EPSS Date: 2025-05-05 (when was this score calculated)

Stakeholder-Specific Vulnerability Categorization (SSVC)

SSVC Exploitation: none

SSVC Technical Impact: partial

SSVC Automatable: false

References

https://nvd.nist.gov/vuln/detail/CVE-2024-46693
https://git.kernel.org/stable/c/1efdbf5323c9360e05066049b97414405e94e087
https://git.kernel.org/stable/c/943b0e7cc646a624bb20a68080f8f1a4a55df41c
https://git.kernel.org/stable/c/3568affcddd68743e25aa3ec1647d9b82797757b

Timeline