跳转到帖子

Amazon Linux AMI: CVE-2022-48988: Security patch for kernel (ALAS-2023-1706)

recommended_posts

发布于
  • Members

Amazon Linux AMI: CVE-2022-48988: Security patch for kernel (ALAS-2023-1706)

Severity
4
CVSS
(AV:L/AC:M/Au:N/C:P/I:P/A:P)
Published
03/17/2023
Created
01/25/2025
Added
01/23/2025
Modified
01/23/2025

Description

In the Linux kernel, the following vulnerability has been resolved:

memcg: fix possible use-after-free in memcg_write_event_control()

memcg_write_event_control() accesses the dentry->d_name of the specified

control fd to route the write call.As a cgroup interface file can't be

renamed, it's safe to access d_name as long as the specified file is a

regular cgroup file.Also, as these cgroup interface files can't be

removed before the directory, it's safe to access the parent too.

Prior to 347c4a874710 ("memcg: remove cgroup_event->cft"), there was a

call to __file_cft() which verified that the specified file is a regular

cgroupfs file before further accesses.The cftype pointer returned from

__file_cft() was no longer necessary and the commit inadvertently dropped

the file type check with it allowing any file to slip through.With the

invarients broken, the d_name and parent accesses can now race against

renames and removals of arbitrary files and cause use-after-free's.

Fix the bug by resurrecting the file type check in __file_cft().Now that

cgroupfs is implemented through kernfs, checking the file operations needs

to go through a layer of indirection.Instead, let's check the superblock

and dentry type.

Solution(s)

  • amazon-linux-upgrade-kernel

References

  • ALAS-2023-1706
  • CVE-2022-48988
  • 查看数 701
  • 已创建
  • 最后回复

参与讨论

你可立刻发布并稍后注册。 如果你有帐户,立刻登录发布帖子。
注意:你的帖子需要版主批准后才能看到。

游客
回帖…