// For flags

CVE-2024-39477

mm/hugetlb: do not call vma_add_reservation upon ENOMEM

Severity Score

5.5
*CVSS v3.1

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:

mm/hugetlb: do not call vma_add_reservation upon ENOMEM

sysbot reported a splat [1] on __unmap_hugepage_range(). This is because
vma_needs_reservation() can return -ENOMEM if
allocate_file_region_entries() fails to allocate the file_region struct
for the reservation.

Check for that and do not call vma_add_reservation() if that is the case,
otherwise region_abort() and region_del() will see that we do not have any
file_regions.

If we detect that vma_needs_reservation() returned -ENOMEM, we clear the
hugetlb_restore_reserve flag as if this reservation was still consumed, so
free_huge_folio() will not increment the resv count.

[1] https://lore.kernel.org/linux-mm/0000000000004096100617c58d54@google.com/T/#ma5983bc1ab18a54910da83416b3f89f3c7ee43aa

En el kernel de Linux, se resolvió la siguiente vulnerabilidad: mm/hugetlb: no llame a vma_add_reservation cuando ENOMEM sysbot informó un splat [1] en __unmap_hugepage_range(). Esto se debe a que vma_needs_reservation() puede devolver -ENOMEM si allocate_file_region_entries() no puede asignar la estructura file_region para la reserva. Verifique eso y no llame a vma_add_reservation() si ese es el caso; de lo contrario, region_abort() y region_del() verán que no tenemos ningún file_regions. Si detectamos que vma_needs_reservation() devolvió -ENOMEM, borramos el indicador hugetlb_restore_reserve como si esta reserva todavía estuviera consumida, por lo que free_huge_folio() no incrementará el recuento de resv. [1] https://lore.kernel.org/linux-mm/0000000000004096100617c58d54@google.com/T/#ma5983bc1ab18a54910da83416b3f89f3c7ee43aa

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-06-25 CVE Reserved
  • 2024-07-05 CVE Published
  • 2024-07-05 EPSS Updated
  • 2024-09-11 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-770: Allocation of Resources Without Limits or Throttling
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"
 >= 6.9 < 6.9.5
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.9 < 6.9.5"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 6.9 < 6.10
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.9 < 6.10"
en
Affected