Description
An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.
No analysis available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-2557-1 | linux-4.19 security update |
Debian DLA |
DLA-2586-1 | linux security update |
Debian DSA |
DSA-4843-1 | linux security update |
EUVD |
EUVD-2020-21931 | An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback. |
Ubuntu USN |
USN-4749-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-4750-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-4751-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-4876-1 | Linux kernel vulnerabilities |
References
History
Wed, 16 Jul 2025 13:45:00 +0000
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Status: PUBLISHED
Assigner: mitre
Published:
Updated: 2024-08-04T16:55:10.494Z
Reserved: 2020-12-04T00:00:00.000Z
Link: CVE-2020-29569
No data.
Status : Modified
Published: 2020-12-15T17:15:14.707
Modified: 2024-11-21T05:24:13.443
Link: CVE-2020-29569
No data.
OpenCVE Enrichment
No data.
Weaknesses
Debian DLA
Debian DSA
EUVD
Ubuntu USN