PT-2024-11225 · Linux+3 · Linux Kernel+3

Shinichiro Kawasaki · Published 2021-05-21 · Updated 2026-03-14 · CVE-2021-47178

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 5.13.0-rc1+ #34

Description A vulnerability has been resolved in the Linux kernel, specifically in the scsi: target: core, where the function smp processor id() was called in preemptible code, triggering a BUG message. This issue was observed when running blktests block/005 on TCMU devices with fileio backend or user:zbc backend, and also at system shutdown when TCMU devices were not cleaned up. The commit 1130b499b4a7 modified the work queue to handle commands and changed 'current->nr cpu allowed' at smp processor id() call, triggering the symptom. To avoid this issue, the CPU ID is now obtained with raw smp processor id() instead.

Recommendations To resolve this issue, update the Linux kernel to a version newer than 5.13.0-rc1+ #34. As a temporary workaround, consider disabling the smp processor id() function until a patch is available. However, since the issue is already resolved by using raw smp processor id() instead, updating the kernel should suffice.

Fix

Weakness Enumeration

CWE-99

CWE-459

Related Identifiers

BDU:2025-13714

CESA-2022_1988

CVE-2021-47178

RHSA-2022:1988

RHSA-2022_1988

Affected Products

Centos

Debian

Linux Kernel

Red Hat

References · 17

• https://osv.dev/vulnerability/UBUNTU-CVE-2021-47178 · Vendor Advisory
• https://git.kernel.org/stable/c/a20b6eaf4f35046a429cde57bee7eb5f13d6857f · Patch
• https://ubuntu.com/security/CVE-2021-47178 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-11-CVE-2021-47178 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2021-47178 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2021-47178 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-47178 · Vendor Advisory
• https://git.kernel.org/stable/c/a222d2794c53f8165de20aa91b39e35e4b72bce9 · Patch
• https://git.kernel.org/stable/c/70ca3c57ff914113f681e657634f7fbfa68e1ad1 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2021-47178 · Security Note
• https://osv.dev/vulnerability/CVE-2021-47178 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-13714 · Security Note
• https://git.linuxtesting.ru/pub/scm/linux/kernel/git/lvc/linux-stable.git/commit/?h=v5.10.180-lvc4&id=a222d2794c53f8165de20aa91b39e35e4b72bce9 · Note
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-47178 · Note
• https://lore.kernel.org/linux-cve-announce/2024032538-CVE-2021-47178-6167@gregkh · Note