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

V3 Legend

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

13 Sep 2024, 16:36

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.5
CWE		CWE-787
First Time		Linux linux Kernel Linux
Summary		(es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf: Se corrige un fallo del verificador del kernel en stacksafe() Daniel Hodges informó de un fallo del verificador del kernel al jugar con sched-ext. Una investigación más profunda muestra que el fallo se debe a un acceso a memoria no válido en stacksafe(). Más específicamente, es el siguiente código: if (exact != NOT_EXACT && old->stack[spi].slot_type[i % BPF_REG_SIZE] != cur->stack[spi].slot_type[i % BPF_REG_SIZE]) return false; La 'i' itera old->allocated_stack. Si cur->allocated_stack < old->allocated_stack, se producirá el acceso fuera de límites. Para solucionar el problema, agregue la comprobación 'i >= cur->allocated_stack' de modo que, si la condición es verdadera, stacksafe() debería fallar. De lo contrario, el acceso a la memoria cur->stack[spi].slot_type[i % BPF_REG_SIZE] es legal.
CPE		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:rc3:::::: cpe:2.3:o:linux:linux_kernel:6.11:rc2::::::
References	~~() https://git.kernel.org/stable/c/6e3987ac310c74bb4dd6a2fa8e46702fe505fb2b -~~	() https://git.kernel.org/stable/c/6e3987ac310c74bb4dd6a2fa8e46702fe505fb2b - Patch
References	~~() https://git.kernel.org/stable/c/7cad3174cc79519bf5f6c4441780264416822c08 -~~	() https://git.kernel.org/stable/c/7cad3174cc79519bf5f6c4441780264416822c08 - Patch
References	~~() https://git.kernel.org/stable/c/bed2eb964c70b780fb55925892a74f26cb590b25 -~~	() https://git.kernel.org/stable/c/bed2eb964c70b780fb55925892a74f26cb590b25 - Patch

11 Sep 2024, 16:15

Type	Values Removed	Values Added
New CVE

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

5.5 /10