CVE-2021-47461

一、漏洞信息
漏洞编号：CVE-2021-47461
漏洞归属组件：kernel
漏洞归属的版本：4.19.140,4.19.194,4.19.90,5.10.0,6.1.0,6.1.14,6.1.19,6.1.5,6.1.6,6.1.8,6.4.0,6.6.0
CVSS V3.0分值：
BaseScore：0.0 None
Vector：CVSS：3.0/
漏洞简述：
In the Linux kernel, the following vulnerability has been resolved:userfaultfd: fix a race between writeprotect and exit_mmap()A race is possible when a process exits, its VMAs are removed byexit_mmap() and at the same time userfaultfd_writeprotect() is called.The race was detected by KASAN on a development kernel, but it appearsto be possible on vanilla kernels as well.Use mmget_not_zero() to prevent the race as done in other userfaultfdoperations.
漏洞公开时间：2024-05-22 15:15:11
漏洞创建时间：2024-05-22 08:28:28
漏洞详情参考链接：
https://nvd.nist.gov/vuln/detail/CVE-2021-47461

更多参考(点击展开)

参考来源	参考链接	来源链接
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca
suse_bugzilla	http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-47461	https://bugzilla.suse.com/show_bug.cgi?id=1225249
suse_bugzilla	https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2021/CVE-2021-47461.mbox	https://bugzilla.suse.com/show_bug.cgi?id=1225249
suse_bugzilla	https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525	https://bugzilla.suse.com/show_bug.cgi?id=1225249
suse_bugzilla	https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a	https://bugzilla.suse.com/show_bug.cgi?id=1225249
suse_bugzilla	https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca	https://bugzilla.suse.com/show_bug.cgi?id=1225249
suse_bugzilla	https://www.cve.org/CVERecord?id=CVE-2021-47461	https://bugzilla.suse.com/show_bug.cgi?id=1225249
suse_bugzilla	https://bugzilla.redhat.com/show_bug.cgi?id=2282896	https://bugzilla.suse.com/show_bug.cgi?id=1225249
redhat_bugzilla	https://lore.kernel.org/linux-cve-announce/2024052225-CVE-2021-47461-a472@gregkh/T	https://bugzilla.redhat.com/show_bug.cgi?id=2282896
redhat_bugzilla	https://access.redhat.com/errata/RHSA-2024:5102	https://bugzilla.redhat.com/show_bug.cgi?id=2282896
redhat_bugzilla	https://access.redhat.com/errata/RHSA-2024:5101	https://bugzilla.redhat.com/show_bug.cgi?id=2282896
redhat_bugzilla	https://access.redhat.com/errata/RHSA-2024:6297	https://bugzilla.redhat.com/show_bug.cgi?id=2282896
redhat_bugzilla	https://access.redhat.com/errata/RHSA-2024:10262	https://bugzilla.redhat.com/show_bug.cgi?id=2282896
ubuntu	https://www.cve.org/CVERecord?id=CVE-2021-47461	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://git.kernel.org/linus/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca (5.15-rc7)	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://nvd.nist.gov/vuln/detail/CVE-2021-47461	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://launchpad.net/bugs/cve/CVE-2021-47461	https://ubuntu.com/security/CVE-2021-47461
ubuntu	https://security-tracker.debian.org/tracker/CVE-2021-47461	https://ubuntu.com/security/CVE-2021-47461
anolis		https://anas.openanolis.cn/cves/detail/CVE-2021-47461

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：

详情(点击展开)

影响的包	修复版本	修复补丁	问题引入补丁	来源
linux		https://git.kernel.org/linus/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca	https://git.kernel.org/linus/63b2d4174c4ad1f40b48d7138e71bcb564c1fe03	ubuntu

二、漏洞分析结构反馈
影响性分析说明：
Reserved.
openEuler评分：
5.5
Vector：CVSS：3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
受影响版本排查(受影响/不受影响)：
1.openEuler-20.03-LTS-SP4(4.19.90):不受影响
2.openEuler-22.03-LTS-SP3(5.10.0):不受影响
3.openEuler-22.03-LTS-SP4(5.10.0):不受影响
4.master(6.6.0):不受影响
5.openEuler-24.03-LTS(6.6.0):不受影响
6.openEuler-24.03-LTS-Next(6.6.0):不受影响
7.openEuler-24.03-LTS-SP1(6.6.0):不受影响

修复是否涉及abi变化(是/否)：
1.openEuler-20.03-LTS-SP4(4.19.90):否
2.openEuler-22.03-LTS-SP3(5.10.0):否
3.master(6.6.0):否
4.openEuler-24.03-LTS(6.6.0):否
5.openEuler-24.03-LTS-Next(6.6.0):否
6.openEuler-22.03-LTS-SP4(5.10.0):否
7.openEuler-24.03-LTS-SP1(6.6.0):否

原因说明：
1.master(6.6.0):不受影响-漏洞代码不能被攻击者触发
2.openEuler-24.03-LTS-Next(6.6.0):不受影响-漏洞代码不能被攻击者触发
3.openEuler-20.03-LTS-SP4(4.19.90):不受影响-漏洞代码不存在
4.openEuler-22.03-LTS-SP3(5.10.0):不受影响-漏洞代码不存在
5.openEuler-22.03-LTS-SP4(5.10.0):不受影响-漏洞代码不存在
6.openEuler-24.03-LTS(6.6.0):不受影响-漏洞代码不存在
7.openEuler-24.03-LTS-SP1(6.6.0):不受影响-漏洞代码不存在

@yangyingliang ,@jiaoff ,@guohaocs2c ,@hanjun-guo ,@woqidaideshi ,@newbeats ,@zhangyi089 ,@colyli ,@thundertown ,@htforge ,@chiqijun ,@lengchao ,@zhujianwei001 ,@kylin-mayukun ,@wangxiongfeng ,@wkfxxx ,@SuperSix173 ,@jentlestea ,@oskernel0719 ,@gasonchen
issue处理注意事项:
1. 当前issue受影响的分支提交pr时, 须在pr描述中填写当前issue编号进行关联, 否则无法关闭当前issue;
2. 模板内容需要填写完整, 无论是受影响或者不受影响都需要填写完整内容,未引入的分支不需要填写, 否则无法关闭当前issue;
3. 以下为模板中需要填写完整的内容, 请复制到评论区回复, 注: 内容的标题名称(影响性分析说明, openEuler评分, 受影响版本排查(受影响/不受影响), 修复是否涉及abi变化(是/否))不能省略,省略后cve-manager将无法正常解析填写内容.

影响性分析说明:

openEuler评分: (评分和向量)

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-22.03-LTS-SP4:
10.openEuler-24.03-LTS:
11.openEuler-24.03-LTS-Next:

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-22.03-LTS-SP4:
10.openEuler-24.03-LTS:
11.openEuler-24.03-LTS-Next:

issue处理具体操作请参考:
https://gitee.com/openeuler/cve-manager/blob/master/cve-vulner-manager/doc/md/manual.md
pr关联issue具体操作请参考:
https://gitee.com/help/articles/4142

Hi openeuler-ci-bot, welcome to the openEuler Community.
I'm the Bot here serving you. You can find the instructions on how to interact with me at Here.
If you have any questions, please contact the SIG: Kernel, and any of the maintainers.

参考网址	关联pr	状态	补丁链接
https://nvd.nist.gov/vuln/detail/CVE-2021-47461	None	None	https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525 https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a
https://www.opencve.io/cve/CVE-2021-47461	None	None	https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525 https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2021-47461
https://security-tracker.debian.org/tracker/CVE-2021-47461	None	None	https://git.kernel.org/linus/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca

说明：补丁链接仅供初步排查参考，实际可用性请人工再次确认，补丁下载验证可使用CVE补丁工具。
若补丁不准确，烦请在此issue下评论 '/report-patch 参考网址补丁链接1,补丁链接2' 反馈正确信息，便于我们不断优化工具，不胜感激。
如 /report-patch https://security-tracker.debian.org/tracker/CVE-2021-3997 https://github.com/systemd/systemd/commit/5b1cf7a9be37e20133c0208005274ce4a5b5c6a1

@guo-mengqi 请确认分支: master,openEuler-20.03-LTS-SP1,openEuler-20.03-LTS-SP4,openEuler-22.03-LTS,openEuler-22.03-LTS-Next,openEuler-22.03-LTS-SP1,openEuler-22.03-LTS-SP2,openEuler-22.03-LTS-SP3,openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-Next 受影响/不受影响.
请确认分支信息是否填写完整,否则将无法关闭当前issue.

CVE-2021-47461

影响性分析说明：
In the Linux kernel, the following vulnerability has been resolved:

userfaultfd: fix a race between writeprotect and exit_mmap()

A race is possible when a process exits, its VMAs are removed by
exit_mmap() and at the same time userfaultfd_writeprotect() is called.

The race was detected by KASAN on a development kernel, but it appears
to be possible on vanilla kernels as well.

Use mmget_not_zero() to prevent the race as done in other userfaultfd
operations.

openEuler评分:(评分和向量)
5.5
CVSS: 3.0/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:N

受影响版本排查(受影响/不受影响):
1.openEuler-20.03-LTS-SP1:不受影响
2.openEuler-20.03-LTS-SP4:不受影响
3.openEuler-22.03-LTS:受影响
4.openEuler-22.03-LTS-SP1:受影响
5.openEuler-22.03-LTS-SP2:受影响
6.openEuler-22.03-LTS-SP3:受影响
7.openEuler-22.03-LTS-SP4:不受影响8.master(6.1.0):不受影响
9.openEuler-22.03-LTS-Next:不受影响
10.openEuler-24.03-LTS:不受影响
11.openEuler-24.03-LTS-Next:不受影响

修复是否涉及abi变化(是/否)：
1.openEuler-20.03-LTS-SP1(4.19.90):否
2.openEuler-20.03-LTS-SP4:否
3.openEuler-22.03-LTS:否
4.openEuler-22.03-LTS-SP1:否
5.openEuler-22.03-LTS-SP2:否
6.openEuler-22.03-LTS-SP3:否
7.master(6.1.0):否
8.openEuler-22.03-LTS-Next:否
9.openEuler-24.03-LTS:否
10.openEuler-24.03-LTS-Next:否
11.openEuler-22.03-LTS-SP4:否

@ 经过 cve-manager 解析, 已分析的内容如下表所示:

状态	需分析	内容
已分析	1.影响性分析说明	In the Linux kernel, the following vulnerability has been resolved:userfaultfd: fix a race between writeprotect and exit_mmap()A race is possible when a process exits, its VMAs are removed byexit_mmap() and at the same time userfaultfd_writeprotect() is called.The race was detected by KASAN on a development kernel, but it appearsto be possible on vanilla kernels as well.Use mmget_not_zero() to prevent the race as done in other userfaultfdoperations.
已分析	2.openEulerScore	5.5
已分析	3.openEulerVector	AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:N
已分析	4.受影响版本排查	openEuler-22.03-LTS:受影响,openEuler-22.03-LTS-SP1:受影响,openEuler-22.03-LTS-SP2:受影响,openEuler-22.03-LTS-SP3:受影响,openEuler-20.03-LTS-SP1:不受影响,openEuler-20.03-LTS-SP4:不受影响,openEuler-22.03-LTS-SP4:不受影响,master:不受影响,openEuler-22.03-LTS-Next:不受影响,openEuler-24.03-LTS:不受影响,openEuler-24.03-LTS-Next:不受影响
已分析	5.修复是否涉及abi变化	openEuler-20.03-LTS-SP1:否,openEuler-20.03-LTS-SP4:否,openEuler-22.03-LTS:否,openEuler-22.03-LTS-SP1:否,openEuler-22.03-LTS-SP2:否,openEuler-22.03-LTS-SP3:否,master:否,openEuler-22.03-LTS-Next:否,openEuler-24.03-LTS:否,openEuler-24.03-LTS-Next:否,openEuler-22.03-LTS-SP4:否

请确认分析内容的准确性, 确认无误后, 您可以进行后续步骤, 否则您可以继续分析.