CVE-2024-26630
mm: cachestat: fix folio read-after-free in cache walk
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
In the Linux kernel, the following vulnerability has been resolved:
mm: cachestat: fix folio read-after-free in cache walk
In cachestat, we access the folio from the page cache's xarray to compute
its page offset, and check for its dirty and writeback flags. However, we
do not hold a reference to the folio before performing these actions,
which means the folio can concurrently be released and reused as another
folio/page/slab.
Get around this altogether by just using xarray's existing machinery for
the folio page offsets and dirty/writeback states.
This changes behavior for tmpfs files to now always report zeroes in their
dirty and writeback counters. This is okay as tmpfs doesn't follow
conventional writeback cache behavior: its pages get "cleaned" during
swapout, after which they're no longer resident etc.
En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm: cachestat: corrige read-after-free la publicación en cache walk En cachestat, accedemos a la publicación desde la matriz x de la caché de la página para calcular su desplazamiento de página y comprobar si está sucia y banderas de reescritura. Sin embargo, no mantenemos una referencia al folio antes de realizar estas acciones, lo que significa que el folio se puede liberar y reutilizar simultáneamente como otro folio/página/losa. Evite esto por completo simplemente utilizando la maquinaria existente de xarray para los desplazamientos de páginas de folio y los estados sucios/de reescritura. Esto cambia el comportamiento de los archivos tmpfs para que ahora siempre informen ceros en sus contadores sucios y de reescritura. Esto está bien ya que tmpfs no sigue el comportamiento de caché de reescritura convencional: sus páginas se "limpian" durante el intercambio, después del cual ya no residen, etc.
Linux versions starting with 6.5 suffer from a read-after-type-change of folio in cachestat() that leads to a kernel pointer leak.
CVSS Scores
SSVC
- Decision:Track
Timeline
- 2024-02-19 CVE Reserved
- 2024-03-13 CVE Published
- 2024-03-14 EPSS Updated
- 2024-08-02 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-416: Use After Free
CAPEC
References (6)
| URL | Tag | Source |
|---|---|---|
| https://git.kernel.org/stable/c/cf264e1329fb0307e044f7675849f9f38b44c11a | Vuln. Introduced |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2024-26630 | 2024-09-11 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2269436 | 2024-09-11 |
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" | >= 6.5 < 6.6.21 Search vendor "Linux" for product "Linux Kernel" and version " >= 6.5 < 6.6.21" | en |
Affected
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| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 6.5 < 6.7.9 Search vendor "Linux" for product "Linux Kernel" and version " >= 6.5 < 6.7.9" | en |
Affected
| ||||||
| Linux Search vendor "Linux" | Linux Kernel Search vendor "Linux" for product "Linux Kernel" | >= 6.5 < 6.8 Search vendor "Linux" for product "Linux Kernel" and version " >= 6.5 < 6.8" | en |
Affected
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