一、漏洞信息
漏洞编号：[CVE-2021-46990](https://nvd.nist.gov/vuln/detail/CVE-2021-46990)
漏洞归属组件：[kernel](https://gitee.com/src-openeuler/kernel)
漏洞归属的版本：4.19.140,4.19.194,4.19.90,5.10.0,6.1.0,6.1.14,6.1.19,6.1.5,6.1.6,6.1.8,6.4.0
CVSS V2.0分值：
BaseScore：0.0 Low
Vector：CVSS：2.0/
漏洞简述：
In the Linux kernel, the following vulnerability has been resolved:powerpc/64s: Fix crashes when toggling entry flush barrierThe entry flush mitigation can be enabled/disabled at runtime via adebugfs file (entry_flush), which causes the kernel to patch itself toenable/disable the relevant mitigations.However depending on which mitigation we re using, it may not be safe todo that patching while other CPUs are active. For example the followingcrash: sleeper[15639]: segfault (11) at c000000000004c20 nip c000000000004c20 lr c000000000004c20Shows that we returned to userspace with a corrupted LR that points intothe kernel, due to executing the partially patched call to the fallbackentry flush (ie. we missed the LR restore).Fix it by doing the patching under stop machine. The CPUs that aren tdoing the patching will be spinning in the core of the stop machinelogic. That is currently sufficient for our purposes, because none ofthe patching we do is to that code or anywhere in the vicinity.
漏洞公开时间：2024-02-28 17:15:37
漏洞创建时间：2024-02-29 01:08:30
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2021-46990
<details>
<summary>更多参考(点击展开)</summary>
| 参考来源 | 参考链接 | 来源链接 |
| ------- | -------- | -------- |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/0b4eb172cc12dc102cd0ad013e53ee4463db9508 | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/0c25a7bb697f2e6ee65b6d63782f675bf129511a | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/2db22ba4e0e103f00e0512e0ecce36ac78c644f8 | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/5bc00fdda1e934c557351a9c751a205293e68cbf | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/8382b15864e5014261b4f36c2aa89723612ee058 | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/aec86b052df6541cc97c5fca44e5934cbea4963b | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/d2e3590ca39ccfd8a5a46d8c7f095cb6c7b9ae92 | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/dd0d6117052faace5440db20fc37175efe921c7d | |
| 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | https://git.kernel.org/stable/c/ee4b7aab93c2631c3bb0753023c5dda592bb666b | |
</details>
漏洞分析指导链接：
https://gitee.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
漏洞数据来源:
openBrain开源漏洞感知系统
漏洞补丁信息：
<details>
<summary>详情(点击展开)</summary>
无
</details>
二、漏洞分析结构反馈
影响性分析说明：
openEuler评分：
受影响版本排查(受影响/不受影响)：
1.master(6.1.0):
2.openEuler-20.03-LTS-SP1(4.19.90):
3.openEuler-20.03-LTS-SP4(4.19.90):
4.openEuler-22.03-LTS(5.10.0):
5.openEuler-22.03-LTS-Next(5.10.0):
6.openEuler-22.03-LTS-SP1(5.10.0):
7.openEuler-22.03-LTS-SP2(5.10.0):
8.openEuler-22.03-LTS-SP3(5.10.0):
9.openEuler-24.03-LTS:
修复是否涉及abi变化(是/否)：
1.master(6.1.0):
2.openEuler-20.03-LTS-SP1(4.19.90):
3.openEuler-20.03-LTS-SP4(4.19.90):
4.openEuler-22.03-LTS(5.10.0):
5.openEuler-22.03-LTS-Next(5.10.0):
6.openEuler-22.03-LTS-SP1(5.10.0):
7.openEuler-22.03-LTS-SP2(5.10.0):
8.openEuler-22.03-LTS-SP3(5.10.0):
9.openEuler-24.03-LTS:
