Linux Kernel up to 6.10.4 notify_handler null pointer dereference

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.10.4. The affected element is the function notify_handler. This manipulation causes null pointer dereference. The identification of this vulnerability is CVE-2024-44937. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.10.4 and classified as critical. Affected by this vulnerability is the function notify_handler. 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: platform/x86: intel-vbtn: Protect ACPI notify handler against recursion Since commit e2ffcda16290 ("ACPI: OSL: Allow Notify () handlers to run on all CPUs") ACPI notify handlers like the intel-vbtn notify_handler() may run on multiple CPU cores racing with themselves. This race gets hit on Dell Venue 7140 tablets when undocking from the keyboard, causing the handler to try and register priv->switches_dev twice, as can be seen from the dev_info() message getting logged twice: [ 83.861800] intel-vbtn INT33D6:00: Registering Intel Virtual Switches input-dev after receiving a switch event [ 83.861858] input: Intel Virtual Switches as /devices/pci0000:00/0000:00:1f.0/PNP0C09:00/INT33D6:00/input/input17 [ 83.861865] intel-vbtn INT33D6:00: Registering Intel Virtual Switches input-dev after receiving a switch event After which things go seriously wrong: [ 83.861872] sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:1f.0/PNP0C09:00/INT33D6:00/input/input17' ... [ 83.861967] kobject: kobject_add_internal failed for input17 with -EEXIST, don't try to register things with the same name in the same directory. [ 83.877338] BUG: kernel NULL pointer dereference, address: 0000000000000018 ... Protect intel-vbtn notify_handler() from racing with itself with a mutex to fix this.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2024-44937 since 08/21/2024. The exploitation appears to be difficult. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 212724 (Ubuntu 22.04 LTS / 24.04 LTS : Linux kernel vulnerabilities (USN-7154-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.10.5 eliminates this vulnerability. Applying the patch 5c9618a3b6ea/e075c3b13a0a 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 (212724). Several companies clearly confirm that VulDB is the primary source for best 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

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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