CVE-2021-47012

In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Fix a use after free in siw_alloc_mr Our code analyzer reported a UAF. In siw_alloc_mr(), it calls siw_mr_add_mem(mr,..). In the implementation of siw_mr_add_mem(), mem is assigned to mr->mem and then mem is freed via kfree(mem) if xa_alloc_cyclic() failed. Here, mr->mem still point to a freed object. After, the execution continue up to the err_out branch of siw_alloc_mr, and the freed mr->mem is used in siw_mr_drop_mem(mr). My patch moves "mr->mem = mem" behind the if (xa_alloc_cyclic(..)<0) {} section, to avoid the 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/3093ee182f01689b89e9f8797b321603e5de4f63	Patch
https://git.kernel.org/stable/c/30b9e92d0b5e5d5dc1101ab856c17009537cbca4	Patch
https://git.kernel.org/stable/c/3e22b88e02c194f6c80867abfef5cc09383461f4	Patch
https://git.kernel.org/stable/c/608a4b90ece039940e9425ee2b39c8beff27e00c	Patch
https://git.kernel.org/stable/c/ad9ce7188432650469a6c7625bf479f5ed0b6155	Patch
https://git.kernel.org/stable/c/3093ee182f01689b89e9f8797b321603e5de4f63	Patch
https://git.kernel.org/stable/c/30b9e92d0b5e5d5dc1101ab856c17009537cbca4	Patch
https://git.kernel.org/stable/c/3e22b88e02c194f6c80867abfef5cc09383461f4	Patch
https://git.kernel.org/stable/c/608a4b90ece039940e9425ee2b39c8beff27e00c	Patch
https://git.kernel.org/stable/c/ad9ce7188432650469a6c7625bf479f5ed0b6155	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2024-02-28 09:15

Updated : 2024-12-09 18:24

NVD link : CVE-2021-47012

Mitre link : CVE-2021-47012

CVE.ORG link : CVE-2021-47012

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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