CVE-2022-49744
What it is
In the Linux kernel, the following vulnerability has been resolved: mm/uffd: fix pte marker when fork() without fork event Patch series "mm: Fixes on pte markers". Patch 1 resolves the syzkiller report from Pengfei. Patch 2 further harden pte markers when used with the recent swapin error markers. The major case is we should persist a swapin error marker after fork(), so child shouldn't read a corrupted page. This patch (of 2): When fork(), dst_vma is not guaranteed to have VM_UFFD_WP even if src may have it and has pte marker installed. The warning is improper along with the comment. The right thing is to inherit the pte marker when needed, or keep the dst pte empty. A vague guess is this happened by an accident when there's the prior patch to introduce src/dst vma into this helper during the uffd-wp feature got developed and I probably messed up in the rebase, since if we replace dst_vma with src_vma the warning & comment it all makes sense too. Hugetlb did exactly the right here (copy_hugetlb_page_range()). Fix the general path. Reproducer: https://github.com/xupengfe/syzkaller_logs/blob/main/221208_115556_copy_page_range/repro.c Bugzilla report: https://bugzilla.kernel.org/show_bug.cgi?id=216808
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Record status
- Analyzed
Affected
- Linux Kernel < 6.1.11
- Linux Kernel 6.2
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-49744.md and follow it. Check whether this project is affected by CVE-2022-49744. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/2d11727655bf931776fb541f5862daf04bd5bf02
- https://git.kernel.org/stable/c/49d6d7fb631345b0f2957a7c4be24ad63903150f