Linux Kernel up to 5.4.150/5.10.70/5.14.9 hwmon devm_i2c_new_dummy_device null pointer dereference

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.4.150/5.10.70/5.14.9. It has been declared as critical. Affected by this vulnerability is the function devm_i2c_new_dummy_device of the component hwmon. Executing a manipulation can lead to null pointer dereference. The identification of this vulnerability is CVE-2021-47384. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.4.150/5.10.70/5.14.9. This vulnerability affects the function devm_i2c_new_dummy_device of the component hwmon. 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: hwmon: (w83793) Fix NULL pointer dereference by removing unnecessary structure field If driver read tmp value sufficient for (tmp & 0x08) && (!(tmp & 0x80)) && ((tmp & 0x7) == ((tmp >> 4) & 0x7)) from device then Null pointer dereference occurs. (It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers) Also lm75[] does not serve a purpose anymore after switching to devm_i2c_new_dummy_device() in w83791d_detect_subclients(). The patch fixes possible NULL pointer dereference by removing lm75[]. Found by Linux Driver Verification project (linuxtesting.org). [groeck: Dropped unnecessary continuation lines, fixed multi-line alignments]

The advisory is available at git.kernel.org. This vulnerability was named CVE-2021-47384 since 05/21/2024. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 207773 (Oracle Linux 8 : kernel (ELSA-2024-7000)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.151, 5.10.71 or 5.14.10 eliminates this vulnerability. Applying the patch 6cb01fe630ea/7c4fd5de39f2/746011193f44/dd4d747ef05a 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 databases at Tenable (207773) and EUVD (EUVD-2021-34389). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.4.150
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.10.40
• 5.10.41
• 5.10.42
• 5.10.43
• 5.10.44
• 5.10.45
• 5.10.46
• 5.10.47
• 5.10.48
• 5.10.49
• 5.10.50
• 5.10.51
• 5.10.52
• 5.10.53
• 5.10.54
• 5.10.55
• 5.10.56
• 5.10.57
• 5.10.58
• 5.10.59
• 5.10.60
• 5.10.61
• 5.10.62
• 5.10.63
• 5.10.64
• 5.10.65
• 5.10.66
• 5.10.67
• 5.10.68
• 5.10.69
• 5.10.70
• 5.14.0
• 5.14.1
• 5.14.2
• 5.14.3
• 5.14.4
• 5.14.5
• 5.14.6
• 5.14.7
• 5.14.8
• 5.14.9

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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