• CVE-2024-26689

发布时间: 2024年5月17日

修改时间: 2025年1月18日

概要

In the Linux kernel, the following vulnerability has been resolved: ceph: prevent use-after-free in encode_cap_msg() In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed. In same file, in "handle_cap_grant()" refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it. encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where the refcount must be increased to prevent "use after free" error.

CVSS v3 指标

NVD openEuler
Confidentiality High None
Attack Vector Local Local
CVSS评分 7.8 5.5
Attack Complexity Low Low
Privileges Required Low Low
Scope Unchanged Unchanged
Integrity High None
User Interaction None None
Availability High High

安全公告

公告名 概要 发布时间
KylinSec-SA-2024-4611 In the Linux kernel, the following vulnerability has been resolved: ceph: prevent use-after-free in encode_cap_msg() In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed. In same file, in "handle_cap_grant()" refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it. encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where the refcount must be increased to prevent "use after free" error. 2024年5月17日
KylinSec-SA-2024-4952 kernel security update 2024年5月17日

影响产品

产品 状态
KY3.4-4A kernel Unaffected
KY3.4-5A kernel Unaffected
KY3.5.1 kernel Fixed
KY3.5.2 kernel Fixed
V6 kernel Unaffected