ID |
CVE-2025-38008
|
Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: fix race condition in unaccepted memory handling
The page allocator tracks the number of zones that have unaccepted memory
using static_branch_enc/dec() and uses that static branch in hot paths to
determine if it needs to deal with unaccepted memory.
Borislav and Thomas pointed out that the tracking is racy: operations on
static_branch are not serialized against adding/removing unaccepted pages
to/from the zone.
Sanity checks inside static_branch machinery detects it:
WARNING: CPU: 0 PID: 10 at kernel/jump_label.c:276 __static_key_slow_dec_cpuslocked+0x8e/0xa0
The comment around the WARN() explains the problem:
/*
* Warn about the '-1' case though; since that means a
* decrement is concurrent with a first (0->1) increment. IOW
* people are trying to disable something that wasn't yet fully
* enabled. This suggests an ordering problem on the user side.
*/
The effect of this static_branch optimization is only visible on
microbenchmark.
Instead of adding more complexity around it, remove it altogether. |
Reference |
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CVSS |
Base: | 0.0 |
Impact: | None |
Exploitability: | None |
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Pristup |
Vektor | Složenost | Autentikacija |
None |
None |
None |
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Impact |
Povjerljivost | Cjelovitost | Dostupnost |
None |
None |
None |
|
CVSS vektor |
None |
Zadnje važnije ažuriranje |
18-06-2025 - 13:46 |
Objavljeno |
18-06-2025 - 10:15 |