| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: 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) |
| <schedule away> |
| pmic_glink_ucsi_register() |
| ucsi_register() |
| pmic_glink_ucsi_read_version() |
| pmic_glink_ucsi_read() |
| pmic_glink_ucsi_read() |
| pmic_glink_send(ucsi->client) |
| <client is NULL BAD> |
| 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 protection domain registry is populated at the |
| time of registration, which by the introduction of commit '1ebcde047c54 |
| ("soc: qcom: add pd-mapper implementation")' became much more likely. |
| |
| The Linux kernel CVE team has assigned CVE-2024-46693 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.3 with commit 58ef4ece1e41ac525db3e79529909683325d85df and fixed in 6.6.49 with commit 1efdbf5323c9360e05066049b97414405e94e087 |
| Issue introduced in 6.3 with commit 58ef4ece1e41ac525db3e79529909683325d85df and fixed in 6.10.8 with commit 943b0e7cc646a624bb20a68080f8f1a4a55df41c |
| Issue introduced in 6.3 with commit 58ef4ece1e41ac525db3e79529909683325d85df and fixed in 6.11 with commit 3568affcddd68743e25aa3ec1647d9b82797757b |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-46693 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/power/supply/qcom_battmgr.c |
| drivers/soc/qcom/pmic_glink.c |
| drivers/soc/qcom/pmic_glink_altmode.c |
| drivers/usb/typec/ucsi/ucsi_glink.c |
| include/linux/soc/qcom/pmic_glink.h |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/1efdbf5323c9360e05066049b97414405e94e087 |
| https://git.kernel.org/stable/c/943b0e7cc646a624bb20a68080f8f1a4a55df41c |
| https://git.kernel.org/stable/c/3568affcddd68743e25aa3ec1647d9b82797757b |
