CVE-2024-26768

LoongArch: Change acpi_core_pic[NR_CPUS] to acpi_core_pic[MAX_CORE_PIC]

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

In the Linux kernel, the following vulnerability has been resolved:

LoongArch: Change acpi_core_pic[NR_CPUS] to acpi_core_pic[MAX_CORE_PIC]

With default config, the value of NR_CPUS is 64. When HW platform has
more then 64 cpus, system will crash on these platforms. MAX_CORE_PIC
is the maximum cpu number in MADT table (max physical number) which can
exceed the supported maximum cpu number (NR_CPUS, max logical number),
but kernel should not crash. Kernel should boot cpus with NR_CPUS, let
the remainder cpus stay in BIOS.

The potential crash reason is that the array acpi_core_pic[NR_CPUS] can
be overflowed when parsing MADT table, and it is obvious that CORE_PIC
should be corresponding to physical core rather than logical core, so it
is better to define the array as acpi_core_pic[MAX_CORE_PIC].

With the patch, system can boot up 64 vcpus with qemu parameter -smp 128,
otherwise system will crash with the following message.

[ 0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000420000004259, era == 90000000037a5f0c, ra == 90000000037a46ec
[ 0.000000] Oops[#1]:
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.8.0-rc2+ #192
[ 0.000000] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
[ 0.000000] pc 90000000037a5f0c ra 90000000037a46ec tp 9000000003c90000 sp 9000000003c93d60
[ 0.000000] a0 0000000000000019 a1 9000000003d93bc0 a2 0000000000000000 a3 9000000003c93bd8
[ 0.000000] a4 9000000003c93a74 a5 9000000083c93a67 a6 9000000003c938f0 a7 0000000000000005
[ 0.000000] t0 0000420000004201 t1 0000000000000000 t2 0000000000000001 t3 0000000000000001
[ 0.000000] t4 0000000000000003 t5 0000000000000000 t6 0000000000000030 t7 0000000000000063
[ 0.000000] t8 0000000000000014 u0 ffffffffffffffff s9 0000000000000000 s0 9000000003caee98
[ 0.000000] s1 90000000041b0480 s2 9000000003c93da0 s3 9000000003c93d98 s4 9000000003c93d90
[ 0.000000] s5 9000000003caa000 s6 000000000a7fd000 s7 000000000f556b60 s8 000000000e0a4330
[ 0.000000] ra: 90000000037a46ec platform_init+0x214/0x250
[ 0.000000] ERA: 90000000037a5f0c efi_runtime_init+0x30/0x94
[ 0.000000] CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
[ 0.000000] PRMD: 00000000 (PPLV0 -PIE -PWE)
[ 0.000000] EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
[ 0.000000] ECFG: 00070800 (LIE=11 VS=7)
[ 0.000000] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
[ 0.000000] BADV: 0000420000004259
[ 0.000000] PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
[ 0.000000] Modules linked in:
[ 0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____))
[ 0.000000] Stack : 9000000003c93a14 9000000003800898 90000000041844f8 90000000037a46ec
[ 0.000000] 000000000a7fd000 0000000008290000 0000000000000000 0000000000000000
[ 0.000000] 0000000000000000 0000000000000000 00000000019d8000 000000000f556b60
[ 0.000000] 000000000a7fd000 000000000f556b08 9000000003ca7700 9000000003800000
[ 0.000000] 9000000003c93e50 9000000003800898 9000000003800108 90000000037a484c
[ 0.000000] 000000000e0a4330 000000000f556b60 000000000a7fd000 000000000f556b08
[ 0.000000] 9000000003ca7700 9000000004184000 0000000000200000 000000000e02b018
[ 0.000000] 000000000a7fd000 90000000037a0790 9000000003800108 0000000000000000
[ 0.000000] 0000000000000000 000000000e0a4330 000000000f556b60 000000000a7fd000
[ 0.000000] 000000000f556b08 000000000eaae298 000000000eaa5040 0000000000200000
[ 0.000000] ...
[ 0.000000] Call Trace:
[ 0.000000] [<90000000037a5f0c>] efi_runtime_init+0x30/0x94
[ 0.000000] [<90000000037a46ec>] platform_init+0x214/0x250
[ 0.000000] [<90000000037a484c>] setup_arch+0x124/0x45c
[ 0.000000] [<90000000037a0790>] start_kernel+0x90/0x670
[ 0.000000] [<900000000378b0d8>] kernel_entry+0xd8/0xdc

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: LoongArch: cambie acpi_core_pic[NR_CPUS] a acpi_core_pic[MAX_CORE_PIC] Con la configuración predeterminada, el valor de NR_CPUS es 64. Cuando la plataforma HW tiene más de 64 cpus, el SYSTEM fallará en estas plataformas . MAX_CORE_PIC es el número máximo de CPU en la tabla MADT (número físico máximo) que puede exceder el número máximo de CPU admitido (NR_CPUS, número lógico máximo), pero el kernel no debería fallar. El kernel debe arrancar los procesadores con NR_CPUS y dejar que los procesadores restantes permanezcan en el BIOS. La posible razón del fallo es que la matriz acpi_core_pic[NR_CPUS] puede desbordarse al analizar la tabla MADT, y es obvio que CORE_PIC debe corresponder al núcleo físico en lugar del núcleo lógico, por lo que es mejor definir la matriz como acpi_core_pic[MAX_CORE_PIC] . Con el parche, el SYSTEM puede iniciar 64 vcpus con el parámetro qemu -smp 128; de lo contrario, el SYSTEM fallará con el siguiente mensaje. [ 0.000000] CPU 0 No se puede manejar la solicitud de paginación del kernel en la dirección virtual 0000420000004259, era == 90000000037a5f0c, ra == 90000000037a46ec [ 0.000000] Ups[#1]: [ 0.000000] CPU: 0 PID: 0 Comm: intercambiador No contaminado 6.8. 0-rc2+ #192 [0.000000] Nombre de hardware: QEMU QEMU Máquina virtual, BIOS desconocido 2/2/2022 [0.000000] pc 90000000037a5f0c ra 90000000037a46ec tp 9000000003c90000 sp 9000000003c93 d60 [ 0.000000] a0 0000000000000019 a1 9000000003d93bc0 a2 0000000000000000 a3 9000000003c93bd8 [ 0.000000] a4 9000000003c93a74 a5 9000000083c93a67 a6 9000000003c938f0 a7 0000000000000005 [ 0.000000] t0 0000420000004201 t1 00000000000000000 t2 0000000000000000 1 t3 0000000000000001 [ 0,000000] t4 0000000000000003 t5 0000000000000000 t6 0000000000000030 t7 0000000000000063 [ 0,000000] t8 0000 000000000014 u0 ffffffffffffffff s9 0000000000000000 s0 9000000003caee98 [ 0.000000] s1 90000000041b0480 s2 9000000003c93da0 s3 9000000003 c93d98 s4 9000000003c93d90 [ 0.000000] s5 9000000003caa000 s6 000000000a7fd000 s7 000000000f556b60 s8 000000000e0a4330 [ 0.000000] ra: 90000000037a46ec platform_init+ 0x214/0x250 [ 0.000000] ERA: 90000000037a5f0c efi_runtime_init+0x30/0x94 [ 0.000000] CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) [ 0.000000] PRMD: 00000000 (PPLV0 -PIE -PWE) [ 0.000000] EUEN: 00000000 (-FPE -SXE -ASXE -BTE) [ 0.000000] ECFG: 00070800 (LIE=11 VS=7) [ 0.000000] ESTAT: 00010000 [PIL] (IS= ECode=1 EssubCode=0) [ 0.000000] BADV: 0000420000004259 [ 0.000000] PRID: 0014c010 (Loongson-64bit, Loongson-3A5000) [ 0.0000 00] Módulos vinculados en: [ 0.000000] Proceso swapper (pid: 0, threadinfo=(____ptrval____), tarea=(____ptrval____)) [0.000000] Pila: 9000000003c93a14 9000000003800898 90000000041844f8 90000000037a46ec [0.000000] 000000000a7fd000 0000000008290000 0000000000000000 0000000000000000 [ 0.000000] 00000000000000000 0000000000000000 00000000019d 8000 000000000f556b60 [ 0,000000] 000000000a7fd000 000000000f556b08 9000000003ca7700 9000000003800000 [ 0,000000 ] 9000000003c93e50 9000000003800898 9000000003800108 90000000037a484c [ 0.000000] 000000000e0a4330 000000000f556b60 00000000 0a7fd000 000000000f556b08 [ 0.000000] 9000000003ca7700 9000000004184000 0000000000200000 000000000e02b018 [ 0.000000] 000000000a 7fd000 90000000037a0790 9000000003800108 0000000000000000 [ 0.000000] 00000000000000000 000000000e0a4330 000000000f556b60 00000 0000a7fd000 [ 0.000000] 000000000f556b08 000000000eaae298 000000000eaa5040 0000000000200000 [ 0.000000] ... [ 0.000000] Llamar Seguimiento: [ 0.000000] [<90000000037a5f0c>] efi_runtime_init+0x30/0x94 [ 0.000000] [<90000000037a46ec>] platform_init+0x214/0x250 [ 0.000000] [<90000000037a48 4c>] setup_arch+0x124/0x45c [ 0.000000] [<90000000037a0790>] start_kernel +0x90/0x670 [ 0.000000] [<900000000378b0d8>] entrada_kernel+0xd8/0xdc

*Credits: N/A

CVSS Scores

CISAv3.1 6.5

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

None

Availability

High

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2024-02-19 CVE Reserved
2024-04-03 CVE Published
2024-04-04 EPSS Updated
2024-12-19 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CAPEC

References (4)

URL	Tag	Source
https://git.kernel.org/stable/c/fa96b57c149061f71a70bd6582d995f6424fbbf4	Vuln. Introduced

URL	Date	SRC

URL	Date	SRC
https://git.kernel.org/stable/c/88e189bd16e5889e44a41b3309558ebab78b9280	2024-03-01
https://git.kernel.org/stable/c/0f6810e39898af2d2cabd9313e4dbc945fb5dfdd	2024-03-01
https://git.kernel.org/stable/c/4551b30525cf3d2f026b92401ffe241eb04dfebe	2024-02-06

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.19 < 6.6.19 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.19 < 6.6.19"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.19 < 6.7.7 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.19 < 6.7.7"		en		Affected
Linux Search vendor "Linux"		Linux Kernel Search vendor "Linux" for product "Linux Kernel"				>= 5.19 < 6.8 Search vendor "Linux" for product "Linux Kernel" and version " >= 5.19 < 6.8"		en		Affected