Azure Linux 3.0 安全性更新核心 (CVE-2024-47679)
medium Nessus Plugin ID 215348
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-2024-47679 公告中提及的一個弱點影響。- 已解決 Linux 核心中的下列弱點：vfs: fix race between evice_inodes() and find_inode()&iput() Hi, all Recently I noticed a bug[1] in btrfs, after digged it into and I believe it'a race in vfs. Let's assume there's a inode (ie ino 261) with i_count 1 is called by iput(), and there's a concurrent thread calling generic_shutdown_super(). cpu0: cpu1: iput() // i_count is 1
->spin_lock(inode) ->December i_count to 0 ->iput_final() generic_shutdown_super() ->__inode_add_lru()
->evict_inodes() // cause some reason[2] ->if (atomic_read(inode->i_count)) continue; // return before // inode 261 passed the above check // list_lru_add_obj() // and then schedule out ->spin_unlock() // note here: the inode 261 // was still at sb list and hash list, // and I_FREEING|I_WILL_FREE was not been set btrfs_iget() // after some function calls ->find_inode() // found the above inode 261 ->spin_lock(inode) // check I_FREEING|I_WILL_FREE // and passed ->__iget() ->spin_unlock(inode) // schedule back
->spin_lock(inode) // check (I_NEW|I_FREEING|I_WILL_FREE) flags, // passed and set I_FREEING iput()
->spin_unlock(inode) ->spin_lock(inode) ->evict(December/ dec i_count to 0 ->iput_final() ->spin_unlock()
->evict() Now, we have two threads simultaneously evicting the same inoMay which may trigger the BUG(inode->i_state & I_CLEAR) statement both within clear_inode() and iput(). To fix the bug, recheck the inode->i_count after holding i_lock. Because in the most scenarios, the first check is valid, and the overhead of spin_lock() can be reduced. If there is any misunderstanding, please let me know, thanks. [1]:
https://lore.kernel.org/linux-btrfs/[email protected]/ [2]: The reason might be 1.
SB_ACTIVE was removed or 2. mapping_shrinkable() return false when I reproduced the bug. (CVE-2024-47679)
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: 215348
檔案名稱: azure_linux_CVE-2024-47679.nasl
版本: 1.1
類型: local
已發布: 2025/2/10
已更新: 2025/2/10
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-2024-47679
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:kernel-dtb, 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-accessibility, p-cpe:/a:microsoft:azure_linux:kernel-tools
必要的 KB 項目: Host/local_checks_enabled, Host/cpu, Host/AzureLinux/release, Host/AzureLinux/rpm-list
可輕鬆利用: No known exploits are available
修補程式發佈日期: 2024/12/10
弱點發布日期: 2024/10/21
參考資訊
CVE: CVE-2024-47679