Description
In the Linux kernel, the following vulnerability has been resolved:
iommu/amd/iommu_v2: Fix pasid_state refcount dec hit 0 warning on pasid unbind
When unbinding pasid - a race condition exists vs outstanding page faults.
To prevent this, the pasid_state object contains a refcount. * set to 1 on pasid bind * incremented on each ppr notification start * decremented on each ppr notification done * decremented on pasid unbind
Since refcount_dec assumes that refcount will never reach 0: the current implementation causes the following to be invoked on pasid unbind: REFCOUNT_WARN("decrement hit 0; leaking memory")
Fix this issue by changing refcount_dec to refcount_dec_and_test to explicitly handle refcount=1.
Metrics
CVSS 3.1 4.7/10
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HAffected software
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 8bc54824da4e8fcf0ed679cf09ac32f23d83254a, < a50d60b8f2aff46dd7c7edb4a5835cdc4d432c22; >= 8bc54824da4e8fcf0ed679cf09ac32f23d83254a, < 13ed255248dfbbb7f23f9170c7a537fb9ca22c73; >= 8bc54824da4e8fcf0ed679cf09ac32f23d83254a, < 9ccc51be3126b25cfe9351dbffde946c925cc28a; >= 8bc54824da4e8fcf0ed679cf09ac32f23d83254a, < 98d86bf32187db27946ca817c2467a5f2f7aa02f; >= 8bc54824da4e8fcf0ed679cf09ac32f23d83254a, < 534103bcd52ca9c1fecbc70e717b4a538dc4ded8 |
| Linux | Linux | 5.15 |
References
- https://git.kernel.org/stable/c/13ed255248dfbbb7f23f9170c7a537fb9ca22c73Patch
- https://git.kernel.org/stable/c/534103bcd52ca9c1fecbc70e717b4a538dc4ded8Patch
- https://git.kernel.org/stable/c/98d86bf32187db27946ca817c2467a5f2f7aa02fPatch
- https://git.kernel.org/stable/c/9ccc51be3126b25cfe9351dbffde946c925cc28aPatch
- https://git.kernel.org/stable/c/a50d60b8f2aff46dd7c7edb4a5835cdc4d432c22Patch
Timeline
- Published
- Oct 1, 2025
- Last modified
- Jun 17, 2026
- NVD status
- Analyzed