Linux Kernel up to 5.15.139/6.1.63/6.5.12/6.6.2 scsi ibmvfc_get_event null pointer dereference

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.15.139/6.1.63/6.5.12/6.6.2. Affected by this vulnerability is the function ibmvfc_get_event of the component scsi. Executing a manipulation can lead to null pointer dereference. This vulnerability is registered as CVE-2023-52811. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 5.15.139/6.1.63/6.5.12/6.6.2 and classified as critical. This vulnerability affects the function ibmvfc_get_event of the component scsi. 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: scsi: ibmvfc: Remove BUG_ON in the case of an empty event pool In practice the driver should never send more commands than are allocated to a queue's event pool. In the unlikely event that this happens, the code asserts a BUG_ON, and in the case that the kernel is not configured to crash on panic returns a junk event pointer from the empty event list causing things to spiral from there. This BUG_ON is a historical artifact of the ibmvfc driver first being upstreamed, and it is well known now that the use of BUG_ON is bad practice except in the most unrecoverable scenario. There is nothing about this scenario that prevents the driver from recovering and carrying on. Remove the BUG_ON in question from ibmvfc_get_event() and return a NULL pointer in the case of an empty event pool. Update all call sites to ibmvfc_get_event() to check for a NULL pointer and perfrom the appropriate failure or recovery action.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2023-52811. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 207689 (RHEL 8 : kernel (RHSA-2024:6993)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.140, 6.1.64, 6.5.13 or 6.6.3 eliminates this vulnerability. Applying the patch e1d1f79b1929/88984ec47927/d2af4ef80601/8bbe784c2ff2/b39f2d10b86d 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 (207689). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.139
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.1.39
• 6.1.40
• 6.1.41
• 6.1.42
• 6.1.43
• 6.1.44
• 6.1.45
• 6.1.46
• 6.1.47
• 6.1.48
• 6.1.49
• 6.1.50
• 6.1.51
• 6.1.52
• 6.1.53
• 6.1.54
• 6.1.55
• 6.1.56
• 6.1.57
• 6.1.58
• 6.1.59
• 6.1.60
• 6.1.61
• 6.1.62
• 6.1.63
• 6.5.0
• 6.5.1
• 6.5.2
• 6.5.3
• 6.5.4
• 6.5.5
• 6.5.6
• 6.5.7
• 6.5.8
• 6.5.9
• 6.5.10
• 6.5.11
• 6.5.12
• 6.6.0
• 6.6.1
• 6.6.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion