CVE-2024-45020

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix a kernel verifier crash in stacksafe() Daniel Hodges reported a kernel verifier crash when playing with sched-ext. Further investigation shows that the crash is due to invalid memory access in stacksafe(). More specifically, it is the following code: if (exact != NOT_EXACT && old->stack[spi].slot_type[i % BPF_REG_SIZE] != cur->stack[spi].slot_type[i % BPF_REG_SIZE]) return false; The 'i' iterates old->allocated_stack. If cur->allocated_stack < old->allocated_stack the out-of-bound access will happen. To fix the issue add 'i >= cur->allocated_stack' check such that if the condition is true, stacksafe() should fail. Otherwise, cur->stack[spi].slot_type[i % BPF_REG_SIZE] memory access is legal.

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/6e3987ac310c74bb4dd6a2fa8e46702fe505fb2b	Patch
https://git.kernel.org/stable/c/7cad3174cc79519bf5f6c4441780264416822c08	Patch
https://git.kernel.org/stable/c/bed2eb964c70b780fb55925892a74f26cb590b25	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:6.11:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.11:rc2::::::
	cpe:2.3:o:linux:linux_kernel:6.11:rc3::::::

History

No history.

Information

Published : 2024-09-11 16:15

Updated : 2024-09-13 16:36

NVD link : CVE-2024-45020

Mitre link : CVE-2024-45020

CVE.ORG link : CVE-2024-45020

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-787

Out-of-bounds Write

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