CVE-2025-38071
Published: June 21, 2025Last modified: June 21, 2025
Description
In the Linux kernel, the following vulnerability has been resolved: x86/mm: Check return value from memblock_phys_alloc_range() At least with CONFIG_PHYSICAL_START=0x100000, if there is < 4 MiB of contiguous free memory available at this point, the kernel will crash and burn because memblock_phys_alloc_range() returns 0 on failure, which leads memblock_phys_free() to throw the first 4 MiB of physical memory to the wolves. At a minimum it should fail gracefully with a meaningful diagnostic, but in fact everything seems to work fine without the weird reserve allocation.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.141-r0) |
| 25 LTS | linux-lts | Fixed (6.12.41-r0) | |
| Stream | linux-lts | Fixed (6.12.41-r0) |
References
- https://git.kernel.org/stable/c/631ca8909fd5c62b9fda9edda93924311a78a9c4
- https://git.kernel.org/stable/c/8c18c904d301ffeb33b071eadc55cd6131e1e9be
- https://git.kernel.org/stable/c/bffd5f2815c5234d609725cd0dc2f4bc5de2fc67
- https://git.kernel.org/stable/c/c6f2694c580c27dca0cf7546ee9b4bfa6b940e38
- https://git.kernel.org/stable/c/dde4800d2b0f68b945fd81d4fc2d4a10ae25f743
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html