PT-2024-11417 · Linux+2 · Linux Kernel+2
Andrey Grodzovsky
+1
·
Published
2021-10-01
·
Updated
2026-03-14
·
CVE-2021-47421
CVSS v3.1
5.5
Medium
| 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 (affected versions not specified)
Description
The issue arises when a PCI error state
pci channel io normal is detected, leading to a report of PCI ERS RESULT CAN RECOVER status to the PCI driver. This causes the PCI driver to continue executing the PCI resume callback report resume by pci walk bridge, which then goes into amdgpu pci resume. Here, a write lock is released unconditionally without being acquired first, resulting in a deadlock when other threads attempt to acquire the read lock. The estimated number of potentially affected devices worldwide is not available. There is no information about real-world incidents where this issue was exploited.Technical details about exploitation include:
- The
amdgpu pci resumefunction is involved in the issue. - The
pci channel stateis cached in theamdgpu devicestructure to handle the case ofpci channel io frozen. - The
pci walk bridgeandreport resumecallbacks are part of the execution flow leading to the deadlock.
Recommendations
At the moment, there is no information about a newer version that contains a fix for this vulnerability.
Improper Locking
Found an issue in the description? Have something to add? Feel free to write us 👾
Weakness Enumeration
Related Identifiers
Affected Products
Debian
Linux Kernel
Suse