Azure Linux 3.0 安全性更新核心 (CVE-2025-37988)
medium Nessus Plugin ID 295221
語言:
概要
遠端 Azure Linux 主機缺少一個或多個安全性更新。說明
遠端 Azure Linux 3.0 主機上安裝的核心版本比測試版舊。因此，此版本會受到 CVE-2025-37988 公告中提及的一個弱點影響。- 已解決 Linux 核心中的下列弱點：fix a couple of races in MNT_TREE_BENEATH handling by do_move_mount() Normally do_lock_mount(path, _) is locking a mountpoint pinned by *path and at the time when matching unlock_mount() unlocks that location it is still pinned by the same thing. Unfortunately, for 'beneath' case it's no longer that simple - the object being locked is not the one *path points to. It's the mountpoint of path->mnt. The thing is, without sufficient locking
->mnt_parent May change under us and none of the locks are held at that point. The rules are * mount_lock stabilizes m->mnt_parent for any mount m. * namespace_sem stabilizes m->mnt_parent, provided that m is mounted. * if either of the above holds and refcount of m is positive, we are guaranteed the same for refcount of m->mnt_parent. namespace_sem nests inside inode_lock(), so do_lock_mount() has to take inode_lock() before grabbing namespace_sem. It does recheck that path->mnt is still mounted in the same place after getting namespace_sem, and it does take care to pin the dentry. It is needed, since otherwise we might end up with racing mount --move (or umount) happening while we were getting locks; in that case dentry would no longer be a mountpoint and could've been evicted on memory pressure along with its inode - not something you want when grabbing lock on that inode. However, pinning a dentry is not enough - the matching mount is also pinned only by the fact that path->mnt is mounted on top it and at that point we are not holding any locks whatsoever, so the same kind of races could end up with all references to that mount gone just as we are about to enter inode_lock(). If that happens, we are left with filesystem being shut down while we are holding a dentry reference on it; results are not pretty. What we need to do is grab both dentry and mount at the same time; that makes inode_lock() safe *and* avoids the problem with fs getting shut down under us. After taking namespace_sem we verify that path->mnt is still mounted (which stabilizes its ->mnt_parent) and check that it's still mounted at the same place. From that point on to the matching namespace_unlock() we are guaranteed that mount/dentry pair we'd grabbed are also pinned by being the mountpoint of path->mnt, so we can quietly drop both the dentry reference (as the current code does) and mnt one - it's OK to do under namespace_sem, since we are not dropping the final refs. That solves the problem on do_lock_mount() side; unlock_mount() also has one, since dentry is guaranteed to stay pinned only until the namespace_unlock(). That's easy to fix - just have inode_unlock() done earlier, while it's still pinned by mp->m_dentry. (CVE-2025-37988)
請注意，Nessus 並未測試此問題，而是僅依據應用程式自我報告的版本號碼作出判斷。
解決方案
更新受影響的套件。另請參閱
Plugin 詳細資訊
嚴重性: Medium
ID: 295221
檔案名稱: azure_linux_CVE-2025-37988.nasl
版本: 1.1
類型: local
已發布: 2026/1/22
已更新: 2026/1/22
支援的感應器: Nessus
風險資訊
VPR
風險因素: Medium
分數: 4.4
CVSS v2
風險因素: Low
基本分數: 3.8
時間性分數: 2.8
媒介: CVSS2#AV:L/AC:H/Au:S/C:N/I:N/A:C
CVSS 評分資料來源: CVE-2025-37988
CVSS v3
風險因素: Medium
基本分數: 4.7
時間性分數: 4.1
媒介: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
時間媒介: CVSS:3.0/E:U/RL:O/RC:C
弱點資訊
CPE: p-cpe:/a:microsoft:azure_linux:kernel-debuginfo, p-cpe:/a:microsoft:azure_linux:kernel-devel, p-cpe:/a:microsoft:azure_linux:kernel-drivers-gpu, p-cpe:/a:microsoft:azure_linux:python3-perf, p-cpe:/a:microsoft:azure_linux:kernel-docs, x-cpe:/o:microsoft:azure_linux, p-cpe:/a:microsoft:azure_linux:kernel, p-cpe:/a:microsoft:azure_linux:kernel-drivers-sound, p-cpe:/a:microsoft:azure_linux:bpftool, p-cpe:/a:microsoft:azure_linux:kernel-drivers-intree-amdgpu, p-cpe:/a:microsoft:azure_linux:kernel-drivers-accessibility, p-cpe:/a:microsoft:azure_linux:kernel-tools
必要的 KB 項目: Host/local_checks_enabled, Host/AzureLinux/release, Host/AzureLinux/rpm-list, Host/cpu
可輕鬆利用: No known exploits are available
修補程式發佈日期: 2025/7/8
弱點發布日期: 2025/5/20
參考資訊
CVE: CVE-2025-37988