// For flags

CVE-2021-47577

io-wq: check for wq exit after adding new worker task_work

Severity Score

"-"
*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

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

io-wq: check for wq exit after adding new worker task_work

We check IO_WQ_BIT_EXIT before attempting to create a new worker, and
wq exit cancels pending work if we have any. But it's possible to have
a race between the two, where creation checks exit finding it not set,
but we're in the process of exiting. The exit side will cancel pending
creation task_work, but there's a gap where we add task_work after we've
canceled existing creations at exit time.

Fix this by checking the EXIT bit post adding the creation task_work.
If it's set, run the same cancelation that exit does.

En el kernel de Linux se ha resuelto la siguiente vulnerabilidad: io-wq: comprueba la salida de wq después de agregar un nuevo trabajador task_work Comprobamos IO_WQ_BIT_EXIT antes de intentar crear un nuevo trabajador, y wq exit cancela el trabajo pendiente si tenemos alguno. Pero es posible tener una carrera entre los dos, donde las comprobaciones de creación salen y descubren que no está configurado, pero estamos en el proceso de salir. El lado de salida cancelará la creación pendiente task_work, pero hay un espacio en el que agregamos task_work después de haber cancelado las creaciones existentes en el momento de la salida. Solucione este problema marcando la publicación del bit EXIT agregando la tarea de creación_trabajo. Si está configurado, ejecute la misma cancelación que realiza la salida.

*Credits: N/A
CVSS Scores
Attack Vector
-
Attack Complexity
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Privileges Required
-
User Interaction
-
Scope
-
Confidentiality
-
Integrity
-
Availability
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* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-05-24 CVE Reserved
  • 2024-06-19 CVE Published
  • 2024-06-20 EPSS Updated
  • 2024-08-04 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"
 < 5.15.11
Search vendor "Linux" for product "Linux Kernel" and version " < 5.15.11"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 < 5.16
Search vendor "Linux" for product "Linux Kernel" and version " < 5.16"
en
Affected