Linux/Unix 主机中安装的一个或多个程序包受到一个漏洞影响，而供应商没有提供补丁程序。

  - ftrace修复 ftrace_modify_direct_caller 中的递归锁定 direct_mutex Naveen 报告了示例 ftrace-direct-modify.ko 的 direct_mutex 递归锁定[ 74.762406] 警告已检测到可能的递归锁定 [ 74.762887] 6.0.0-rc6+ #33 未受感染 [ 74.763216]
    ------------------------------------------- [ 74.763672] event- sample-fn/1084 正在尝试获取锁定
    [ 74.764152] ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}位于 \ register_ftrace_function+0x1f/0x180 [74.764922] [ 74.764922] 但任务已持有锁定[ 74.765421] ffffffff86c9d6b0 (direct_mutex) ){+.+.}-{3:3}位于\modify_ftrace_direct+0x34/0x1f0 [ 74.766142] [ 74.766142] 其他可能帮助我们调试此问题的信息[ 74.766701] 可能不安全的锁定情况[ 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] 可能是由于缺少锁定嵌套符号所致 [74.768750] [ 74.769332] 1 个锁定由 event-sample-fn/1084 持有[ 74.769731] #0ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}at: \ modify_ftrace_direct+0x34/0x1f0 [ 74.770496] [ 74.770496] 堆栈回溯 [ 74.770884] CPU: 4 PID1084 Commevent-sample-fn 未受感染... [ 74.771498] 硬件名称
    QEMU Standard PC(i440FX + PIIX, 1996)... [ 74.772474] 调用跟踪[ 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> 通过使用 ftrace_modify_direct_caller 中的 register_ftrace_function_nolock 修复此问题。 (CVE-2022-50648)

请注意，Nessus 依赖供应商报告的程序包是否存在进行判断。

检测

Linux Distros 未修补的漏洞：CVE-2022-50648

medium Nessus 插件 ID 278093

版本 1.8