Linux Kernel up to 6.10.7 ucsi_unregister null pointer dereference

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.10.7. This affects the function ucsi_unregister. This manipulation causes null pointer dereference. This vulnerability is handled as CVE-2024-46691. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.10.7. It has been declared as critical. Affected by this vulnerability is the function ucsi_unregister. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: Move unregister out of atomic section Commit '9329933699b3 ("soc: qcom: pmic_glink: Make client-lock non-sleeping")' moved the pmic_glink client list under a spinlock, as it is accessed by the rpmsg/glink callback, which in turn is invoked from IRQ context. This means that ucsi_unregister() is now called from atomic context, which isn't feasible as it's expecting a sleepable context. An effort is under way to get GLINK to invoke its callbacks in a sleepable context, but until then lets schedule the unregistration. A side effect of this is that ucsi_unregister() can now happen after the remote processor, and thereby the communication link with it, is gone. pmic_glink_send() is amended with a check to avoid the resulting NULL pointer dereference. This does however result in the user being informed about this error by the following entry in the kernel log: ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: failed to send UCSI write request: -5

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2024-46691 since 09/11/2024. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 208425 (SUSE SLES15 Security Update : kernel (SUSE-SU-2024:3553-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.10.8 eliminates this vulnerability. Applying the patch 095b0001aefd/11bb2ffb6793 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (208425). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.10.0
• 6.10.1
• 6.10.2
• 6.10.3
• 6.10.4
• 6.10.5
• 6.10.6
• 6.10.7

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Be aware that VulDB is the high quality source for vulnerability data.

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