CVE-2021-47649

In the Linux kernel, the following vulnerability has been resolved: udmabuf: validate ubuf->pagecount Syzbot has reported GPF in sg_alloc_append_table_from_pages(). The problem was in ubuf->pages == ZERO_PTR. ubuf->pagecount is calculated from arguments passed from user-space. If user creates udmabuf with list.size == 0 then ubuf->pagecount will be also equal to zero; it causes kmalloc_array() to return ZERO_PTR. Fix it by validating ubuf->pagecount before passing it to kmalloc_array().

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/2b6dd600dd72573c23ea180b5b0b2f1813405882	Patch
https://git.kernel.org/stable/c/5d50f851dd307c07ca5591297093f19967c834a9	Patch
https://git.kernel.org/stable/c/811b667cefbea9cb7511a874b169d6a92907137e	Patch
https://git.kernel.org/stable/c/9e9b4a269f84d3230f2af84ff42322db676440d9	Patch
https://git.kernel.org/stable/c/a3728d32fc61eb0fe283cb8ff60b2c8f751e2202	Patch
https://git.kernel.org/stable/c/b267a8118c2b171bf7d67b90ed64154eeab9fae0	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::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2025-02-26 06:37

Updated : 2025-10-14 19:08

NVD link : CVE-2021-47649

Mitre link : CVE-2021-47649

CVE.ORG link : CVE-2021-47649

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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