ID |
CVE-2025-38282
|
Sažetak |
In the Linux kernel, the following vulnerability has been resolved:
kernfs: Relax constraint in draining guard
The active reference lifecycle provides the break/unbreak mechanism but
the active reference is not truly active after unbreak -- callers don't
use it afterwards but it's important for proper pairing of kn->active
counting. Assuming this mechanism is in place, the WARN check in
kernfs_should_drain_open_files() is too sensitive -- it may transiently
catch those (rightful) callers between
kernfs_unbreak_active_protection() and kernfs_put_active() as found out by Chen
Ridong:
kernfs_remove_by_name_ns kernfs_get_active // active=1
__kernfs_remove // active=0x80000002
kernfs_drain ...
wait_event
//waiting (active == 0x80000001)
kernfs_break_active_protection
// active = 0x80000001
// continue
kernfs_unbreak_active_protection
// active = 0x80000002
...
kernfs_should_drain_open_files
// warning occurs
kernfs_put_active
To avoid the false positives (mind panic_on_warn) remove the check altogether.
(This is meant as quick fix, I think active reference break/unbreak may be
simplified with larger rework.) |
Reference |
|
CVSS |
Base: | 0.0 |
Impact: | None |
Exploitability: | None |
|
Pristup |
Vektor | Složenost | Autentikacija |
None |
None |
None |
|
Impact |
Povjerljivost | Cjelovitost | Dostupnost |
None |
None |
None |
|
CVSS vektor |
None |
Zadnje važnije ažuriranje |
10-07-2025 - 13:17 |
Objavljeno |
10-07-2025 - 08:15 |