Executive Summary
| Informations | |||
|---|---|---|---|
| Name | CVE-2021-47256 | First vendor Publication | 2024-05-21 |
| Vendor | Cve | Last vendor Modification | 2025-04-30 |
Security-Database Scoring CVSS v3
| Cvss vector : CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | |||
|---|---|---|---|
| Overall CVSS Score | 5.5 | ||
| Base Score | 5.5 | Environmental Score | 5.5 |
| impact SubScore | 3.6 | Temporal Score | 5.5 |
| Exploitabality Sub Score | 1.8 | ||
| Attack Vector | Local | Attack Complexity | Low |
| Privileges Required | Low | User Interaction | None |
| Scope | Unchanged | Confidentiality Impact | None |
| Integrity Impact | None | Availability Impact | High |
| Calculate full CVSS 3.0 Vectors scores | |||
Security-Database Scoring CVSS v2
| Cvss vector : | |||
|---|---|---|---|
| Cvss Base Score | N/A | Attack Range | N/A |
| Cvss Impact Score | N/A | Attack Complexity | N/A |
| Cvss Expoit Score | N/A | Authentication | N/A |
| Calculate full CVSS 2.0 Vectors scores | |||
Detail
| In the Linux kernel, the following vulnerability has been resolved: mm/memory-failure: make sure wait for page writeback in memory_failure Our syzkaller trigger the "BUG_ON(!list_empty(&inode->i_wb_list))" in clear_inode: kernel BUG at fs/inode.c:519! A crash dump of this problem show that someone called __munlock_pagevec to clear page LRU without lock_page: do_mmap -> mmap_region -> do_munmap -> munlock_vma_pages_range -> __munlock_pagevec. As a result memory_failure will call identify_page_state without wait_on_page_writeback. And after truncate_error_page clear the mapping of this page. end_page_writeback won't call sb_clear_inode_writeback to clear inode->i_wb_list. That will trigger BUG_ON in clear_inode! Fix it by checking PageWriteback too to help determine should we skip wait_on_page_writeback. |
Original Source
| Url : http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-47256 |
CPE : Common Platform Enumeration
Sources (Detail)
Alert History
| Date | Informations |
|---|---|
| 2025-05-27 01:50:06 |
|
| 2024-11-25 09:25:28 |
|
| 2024-05-21 21:27:27 |
|
