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。

  - ftrace修正 ftrace_modify_direct_caller 中的遞回鎖定 direct_mutex Naveen 報告範例 ftrace-direct-modify.ko 發生 direct_mutex 的遞回鎖定 [ 74.762406] 警告偵測到可能的遞回鎖定 [ 74.762887] 6.0.0-rc6+ #33 未受污染 [ 74.763216]
    -------------------------------------------------------- [ 74.763672] event- sample-fn/1084 嘗試取得鎖定
    [ 74.764152] ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}, at: \ register_ftrace_function+0x1f/0x180 [74.764922] [ 74.764922]but task 已保留鎖定[ 74.765421] ffffffff86c9d6b0 (direct_mutex ){+.+.}-{3:3}, at: \ modify_ftrace_direct+0x34/0x1f0 [ 74.766142] [ 74.766142] 可協助我們除錯此項目的其他資訊[ 74.766701] 可能的不安全鎖定狀況[ 74.766701] [ 74.767216] CPU0 [ 74.767437] ---- [ 74.767656] lock(direct_mutex); [ 74.767952] lock(direct_mutex); [ 74.768245] [74.768245] *** DEADLOCK *** [ 74.768245] [ 74.768750] 原因可能是缺少鎖定巢狀標記法 [74.768750] [ 74.769332] event-sample-fn/1084 保留了 1 個鎖定[ 74.769731] #0ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}, at: \ modify_ftrace_direct+0x34/0x1f0 [ 74.770496] [ 74.770496] 堆疊反向追踪[ 74.770884] CPU 4 PID1084 通訊event-sample-fn 未受污染... [ 74.771498] 硬體名稱
    QEMU Standard PC (i440FX + PIIX、1996)、... [ 74.772474] 呼叫追踪 [ 74.772696] <TASK> [ 74.772896] dump_stack_lvl+0x44/0x5b [ 74.773223] __lock_acquire.cold.74+0xac/0x2b7 [ 74.773616] lock_acquire+0xd2/0x310 [ 74.773936] ? register_ftrace_function+0x1f/0x180 [ 74.774357] ? lock_is_held_type+0xd8/0x130 [ 74.774744] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.775213]
    __mutex_lock+0x99/0x1010 [ 74.775536] ? register_ftrace_function+0x1f/0x180 [ 74.775954] ? slab_free_freelist_hook.isra.43+0x115/0x160 [ 74.776424] ftrace_set_hash+0x195/0x220 [ 74.776779] ? register_ftrace_function+0x1f/0x180 [ 74.777194] ? kfree+0x3e1/0x440 [ 74.777482] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.777941] __schedule+0xb40/0xb40 [ 74.778258] ? register_ftrace_function+0x1f/0x180 [ 74.778672] ? my_tramp1+0xf/0xf [ftrace_direct_modify] [ 74.779128] register_ftrace_function+0x1f/0x180 [ 74.779527] ? ftrace_set_filter_ip+0x33/0x70 [ 74.779910] ?
    __schedule+0xb40/0xb40 [ 74.780231] ? my_tramp1+0xf/0xf [ftrace_direct_modify] [ 74.780678] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.781147] ftrace_modify_direct_caller+0x5b/0x90 [ 74.781563] ? 0xffffffffa0201000 [ 74.781859] ? my_tramp1+0xf/0xf [ftrace_direct_modify] [ 74.782309] modify_ftrace_direct+0x1b2/0x1f0 [ 74.782690] ? __schedule+0xb40/0xb40 [ 74.783014] ? simple_thread+0x2a/0xb0 [ftrace_direct_modify] [ 74.783508] __schedule+0xb40/0xb40 [ 74.783832] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.784294] simple_thread+0x76/0xb0 [ftrace_direct_modify] [74.784766] kthread+0xf5/0x120 [ 74.785052] ? kthread_complete_and_exit+0x20/0x20 [ 74.785464] ret_from_fork+0x22/0x30 [ 74.785781] </TASK> 使用 ftrace_modify_direct_caller 中的 register_ftrace_function_nolock 修正此問題。 (CVE-2022-50648)

請注意，Nessus 的判定取決於廠商所報告的套件是否存在。

偵測

Linux Distros 未修補的弱點：CVE-2022-50648

medium Nessus Plugin ID 278093

版本 1.1