发布时间: 2024年7月10日
修改时间: 2024年7月10日
In the Linux kernel, the following vulnerability has been resolved: fs/proc/task_mmu: fix loss of young/dirty bits during pagemap scan make_uffd_wp_pte() was previously doing: pte = ptep_get(ptep); ptep_modify_prot_start(ptep); pte = pte_mkuffd_wp(pte); ptep_modify_prot_commit(ptep, pte); But if another thread accessed or dirtied the pte between the first 2 calls, this could lead to loss of that information. Since ptep_modify_prot_start() gets and clears atomically, the following is the correct pattern and prevents any possible race. Any access after the first call would see an invalid pte and cause a fault: pte = ptep_modify_prot_start(ptep); pte = pte_mkuffd_wp(pte); ptep_modify_prot_commit(ptep, pte);
| NVD | openEuler | |
|---|---|---|
| Confidentiality | Low | |
| Attack Vector | Local | |
| CVSS评分 | N/A | 3.9 |
| Attack Complexity | High | |
| Privileges Required | High | |
| Scope | Unchanged | |
| Integrity | Low | |
| User Interaction | None | |
| Availability | Low |
| 公告名 | 概要 | 发布时间 |
|---|---|---|
| KylinSec-SA-2024-3090 | In the Linux kernel, the following vulnerability has been resolved: fs/proc/task_mmu: fix loss of young/dirty bits during pagemap scan make_uffd_wp_pte() was previously doing: pte = ptep_get(ptep); ptep_modify_prot_start(ptep); pte = pte_mkuffd_wp(pte); ptep_modify_prot_commit(ptep, pte); But if another thread accessed or dirtied the pte between the first 2 calls, this could lead to loss of that information. Since ptep_modify_prot_start() gets and clears atomically, the following is the correct pattern and prevents any possible race. Any access after the first call would see an invalid pte and cause a fault: pte = ptep_modify_prot_start(ptep); pte = pte_mkuffd_wp(pte); ptep_modify_prot_commit(ptep, pte); | 2024年7月10日 |
| 产品 | 包 | 状态 |
|---|---|---|
| KY3.4-5A | kernel | Unaffected |
| KY3.5.2 | kernel | Unaffected |
| V6 | kernel | Unaffected |
