tracing/histograms: Fix memory leak problem(CVE-2022-49648)

概要

tracing/histograms: Fix memory leak problem

原文の説明

取得元が公開している説明をそのまま載せています (多くは英語)。

In the Linux kernel, the following vulnerability has been resolved:

tracing/histograms: Fix memory leak problem

This reverts commit 46bbe5c671e06f070428b9be142cc4ee5cedebac.

As commit 46bbe5c671e0 ("tracing: fix double free") said, the
"double free" problem reported by clang static analyzer is:

In parse_var_defs() if there is a problem allocating
var_defs.expr, the earlier var_defs.name is freed.
This free is duplicated by free_var_defs() which frees
the rest of the list.

However, if there is a problem allocating N-th var_defs.expr:

in parse_var_defs(), the freed 'earlier var_defs.name' is
actually the N-th var_defs.name;

then in free_var_defs(), the names from 0th to (N-1)-th are freed;

                IF ALLOCATING PROBLEM HAPPENED HERE!!! -+
                                                         \
                                                          |
  0th           1th                 (N-1)-th      N-th    V
  +-------------+-------------+-----+-------------+-----------

These two frees don't act on same name, so there was no "double free"
problem before. Conversely, after that commit, we get a "memory leak"
problem because the above "N-th var_defs.name" is not freed.

If enable CONFIG_DEBUG_KMEMLEAK and inject a fault at where the N-th
var_defs.expr al…

出典: OSV.dev (Open Source Vulnerabilities) NVD OSV

影響パッケージ

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.19.253"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.20.0"},{"fixed":"5.4.207"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.132"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.9.0"},{"fixed":"5.15.56"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.18.13"}]}]

ディストリビューション別の修正状況

各ディストリビューションが公開している、この CVE の修正パッケージ

Debian DEBIAN-CVE-2022-49648 linux 修正版: 5.10.136-1
Ubuntu UBUNTU-CVE-2022-49648 linux-hwe-edge

概要

原文の説明

影響パッケージ

ディストリビューション別の修正状況

参照URL