CVE-2021-47081

In the Linux kernel, the following vulnerability has been resolved: habanalabs/gaudi: Fix a potential use after free in gaudi_memset_device_memory Our code analyzer reported a uaf. In gaudi_memset_device_memory, cb is get via hl_cb_kernel_create() with 2 refcount. If hl_cs_allocate_job() failed, the execution runs into release_cb branch. One ref of cb is dropped by hl_cb_put(cb) and could be freed if other thread also drops one ref. Then cb is used by cb->id later, which is a potential uaf. My patch add a variable 'id' to accept the value of cb->id before the hl_cb_put(cb) is called, to avoid the potential uaf.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/115726c5d312b462c9d9931ea42becdfa838a076	Patch
https://git.kernel.org/stable/c/b49f5af30b0e4064fbd91e83823a4bfcb2c7a3e7	Patch
https://git.kernel.org/stable/c/115726c5d312b462c9d9931ea42becdfa838a076	Patch
https://git.kernel.org/stable/c/b49f5af30b0e4064fbd91e83823a4bfcb2c7a3e7	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.13:rc1::::::
	cpe:2.3:o:linux:linux_kernel:5.13:rc2::::::

History

09 Dec 2024, 18:45

Type	Values Removed	Values Added
First Time		Linux linux Kernel Linux
CWE		CWE-416
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.8
CPE		cpe:2.3:o:linux:linux_kernel:5.13:rc2:::::: cpe:2.3:o:linux:linux_kernel:5.13:rc1:::::: cpe:2.3:o:linux:linux_kernel::::::::
References	~~() https://git.kernel.org/stable/c/115726c5d312b462c9d9931ea42becdfa838a076 -~~	() https://git.kernel.org/stable/c/115726c5d312b462c9d9931ea42becdfa838a076 - Patch
References	~~() https://git.kernel.org/stable/c/b49f5af30b0e4064fbd91e83823a4bfcb2c7a3e7 -~~	() https://git.kernel.org/stable/c/b49f5af30b0e4064fbd91e83823a4bfcb2c7a3e7 - Patch

Information

Published : 2024-03-01 22:15

Updated : 2024-12-09 18:45

NVD link : CVE-2021-47081

Mitre link : CVE-2021-47081

CVE.ORG link : CVE-2021-47081

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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