Linux Distros 未修補弱點:CVE-2024-47679

medium Nessus Plugin ID 228532

概要

Linux/Unix 主機上安裝的一個或多個套件存有弱點,供應商表示將不會修補。

說明

Linux/Unix 主機上安裝了一個或多個受到弱點影響的套件,且供應商未提供可用的修補程式。

- 在 Linux 核心中,已解決下列弱點: 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) ->dec 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() // dec i_count to 0 ->iput_final() ->spin_unlock()
->evict() Now, we have two threads simultaneously evicting the same inode, 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 依賴供應商報告的套件存在。

解決方案

目前尚未有已知的解決方案。

Plugin 詳細資訊

嚴重性: Medium

ID: 228532

檔案名稱: unpatched_CVE_2024_47679.nasl

版本: 1.2

類型: local

代理程式: unix

系列: Misc.

已發布: 2025/3/5

已更新: 2025/3/10

支援的感應器: Nessus Agent, 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

必要的 KB 項目: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched

可輕鬆利用: No known exploits are available

弱點發布日期: 2024/10/21

參考資訊

CVE: CVE-2024-47679