CVE-2021-47218

In the Linux kernel, the following vulnerability has been resolved: selinux: fix NULL-pointer dereference when hashtab allocation fails When the hash table slot array allocation fails in hashtab_init(), h->size is left initialized with a non-zero value, but the h->htable pointer is NULL. This may then cause a NULL pointer dereference, since the policydb code relies on the assumption that even after a failed hashtab_init(), hashtab_map() and hashtab_destroy() can be safely called on it. Yet, these detect an empty hashtab only by looking at the size. Fix this by making sure that hashtab_init() always leaves behind a valid empty hashtab when the allocation fails.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/83c8ab8503adf56bf68dafc7a382f4946c87da79	Patch
https://git.kernel.org/stable/c/b17dd53cac769dd13031b0ca34f90cc65e523fab	Patch
https://git.kernel.org/stable/c/dc27f3c5d10c58069672215787a96b4fae01818b	Patch
https://git.kernel.org/stable/c/83c8ab8503adf56bf68dafc7a382f4946c87da79	Patch
https://git.kernel.org/stable/c/b17dd53cac769dd13031b0ca34f90cc65e523fab	Patch
https://git.kernel.org/stable/c/dc27f3c5d10c58069672215787a96b4fae01818b	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:5.16:rc1::::::
	cpe:2.3:o:linux:linux_kernel:5.16:rc2::::::

History

No history.

Information

Published : 2024-04-10 19:15

Updated : 2025-01-14 14:44

NVD link : CVE-2021-47218

Mitre link : CVE-2021-47218

CVE.ORG link : CVE-2021-47218

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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