// For flags

CVE-2024-26796

drivers: perf: ctr_get_width function for legacy is not defined

Severity Score

"-"
*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

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Track
*SSVC
Descriptions

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

drivers: perf: ctr_get_width function for legacy is not defined

With parameters CONFIG_RISCV_PMU_LEGACY=y and CONFIG_RISCV_PMU_SBI=n
linux kernel crashes when you try perf record:

$ perf record ls
[ 46.749286] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[ 46.750199] Oops [#1]
[ 46.750342] Modules linked in:
[ 46.750608] CPU: 0 PID: 107 Comm: perf-exec Not tainted 6.6.0 #2
[ 46.750906] Hardware name: riscv-virtio,qemu (DT)
[ 46.751184] epc : 0x0
[ 46.751430] ra : arch_perf_update_userpage+0x54/0x13e
[ 46.751680] epc : 0000000000000000 ra : ffffffff8072ee52 sp : ff2000000022b8f0
[ 46.751958] gp : ffffffff81505988 tp : ff6000000290d400 t0 : ff2000000022b9c0
[ 46.752229] t1 : 0000000000000001 t2 : 0000000000000003 s0 : ff2000000022b930
[ 46.752451] s1 : ff600000028fb000 a0 : 0000000000000000 a1 : ff600000028fb000
[ 46.752673] a2 : 0000000ae2751268 a3 : 00000000004fb708 a4 : 0000000000000004
[ 46.752895] a5 : 0000000000000000 a6 : 000000000017ffe3 a7 : 00000000000000d2
[ 46.753117] s2 : ff600000028fb000 s3 : 0000000ae2751268 s4 : 0000000000000000
[ 46.753338] s5 : ffffffff8153e290 s6 : ff600000863b9000 s7 : ff60000002961078
[ 46.753562] s8 : ff60000002961048 s9 : ff60000002961058 s10: 0000000000000001
[ 46.753783] s11: 0000000000000018 t3 : ffffffffffffffff t4 : ffffffffffffffff
[ 46.754005] t5 : ff6000000292270c t6 : ff2000000022bb30
[ 46.754179] status: 0000000200000100 badaddr: 0000000000000000 cause: 000000000000000c
[ 46.754653] Code: Unable to access instruction at 0xffffffffffffffec.
[ 46.754939] ---[ end trace 0000000000000000 ]---
[ 46.755131] note: perf-exec[107] exited with irqs disabled
[ 46.755546] note: perf-exec[107] exited with preempt_count 4

This happens because in the legacy case the ctr_get_width function was not
defined, but it is used in arch_perf_update_userpage.

Also remove extra check in riscv_pmu_ctr_get_width_mask

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: controladores: perf: ctr_get_width la función para legado no está definida Con los parámetros CONFIG_RISCV_PMU_LEGACY=y y CONFIG_RISCV_PMU_SBI=n el kernel de Linux falla cuando intenta el registro de rendimiento: $ perf record ls [ 46.749286] No se puede manejar la desreferencia del puntero NULL del kernel en la dirección virtual 0000000000000000 [ 46.750199] Ups [#1] [ 46.750342] Módulos vinculados en: [ 46.750608] CPU: 0 PID: 107 Comm: perf-exec Not tainted 6.6.0 #2 [ 46.750906] Nombre del hardware : riscv-virtio,qemu (DT) [ 46.751184] epc : 0x0 [ 46.751430 ] ra : arch_perf_update_userpage+0x54/0x13e [ 46.751680] epc : 00000000000000000 ra : ffffffff8072ee52 sp : ff20000 00022b8f0 [46.751958] gp: ffffffff81505988 tp: ff6000000290d400 t0: ff2000000022b9c0 [ 46.752229] t1 : 0000000000000001 t2 : 0000000000000003 s0 : ff2000000022b930 [ 46.752451] s1 : ff600000028fb000 a0 : 0000000000000000 a 1: ff600000028fb000 [46.752673] a2: 0000000ae2751268 a3: 00000000004fb708 a4: 00000000000000004 [46.752895] a5: 0000000000000000 a6: 000000000017ffe3 a7: 00000000000000d2 [46.753117] s2: ff600000028fb000 s3: 0000000ae2751268 s4: 0000000000000000 [46.753338] s5: ffffffff8153e290 s6: ff600000863b9000 s7: ff60000002 961078 [46.753562] s8: ff60000002961048 s9: ff60000002961058 s10: 00000000000000001 [46.753783] s11: 0000000000000018 t3: ffffffffffffff ff t4 : ffffffffffffffff [ 46.754005] t5 : ff6000000292270c t6: ff2000000022bb30 [46.754179] estado: 0000000200000100 badaddr: 00000000000000000 causa: 0000000000000000c [46.754653] Código: No se puede acceder instrucción en 0xffffffffffffffec. [ 46.754939] ---[ end trace 0000000000000000 ]--- [ 46.755131] nota: perf-exec[107] salió con irqs deshabilitados [ 46.755546] nota: perf-exec[107] salió con preempt_count 4 Esto sucede porque en el legado En este caso, la función ctr_get_width no se definió, pero se usa en arch_perf_update_userpage. También elimine el control adicional en riscv_pmu_ctr_get_width_mask

*Credits: N/A
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* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-02-19 CVE Reserved
  • 2024-04-04 CVE Published
  • 2024-04-05 EPSS Updated
  • 2024-09-11 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
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"
>= 6.6 < 6.6.21
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.6.21"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.7.9
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.7.9"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.6 < 6.8
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.6 < 6.8"
en
Affected