Description
In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: Don't reset VMBus connection state on error/exit paths
In two places, current code forces vmbus_connection.conn_state to
DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect()
calls vmbus_initiate_unload(), which unloads the VMBus connection
only if the conn_state is CONNECTED. Consequently, the connection
remains and the Hyper-V host might continue to send messages or post
VMBus interrupts.
The problem was introduced in commit 74347a99e73ae ("x86/Hyper-V:
Unload vmbus channel in hv panic callback"), in that
vmbus_initiate_unload() started checking the current connection
state before doing the unload. This commit removed some occurrences
where conn_state was forced to DISCONNECTED, but these two remained,
apparently due to an oversight at the time.
Fix this by not forcing conn_state to DISCONNECTED during VMBus exit,
or if a failure occurs when establishing the connection in the first
place. Whatever value conn_state has at the time is then read by
vmbus_initiate_unload() to determine if there is a connection to
be unloaded.
Drivers: hv: Don't reset VMBus connection state on error/exit paths
In two places, current code forces vmbus_connection.conn_state to
DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect()
calls vmbus_initiate_unload(), which unloads the VMBus connection
only if the conn_state is CONNECTED. Consequently, the connection
remains and the Hyper-V host might continue to send messages or post
VMBus interrupts.
The problem was introduced in commit 74347a99e73ae ("x86/Hyper-V:
Unload vmbus channel in hv panic callback"), in that
vmbus_initiate_unload() started checking the current connection
state before doing the unload. This commit removed some occurrences
where conn_state was forced to DISCONNECTED, but these two remained,
apparently due to an oversight at the time.
Fix this by not forcing conn_state to DISCONNECTED during VMBus exit,
or if a failure occurs when establishing the connection in the first
place. Whatever value conn_state has at the time is then read by
vmbus_initiate_unload() to determine if there is a connection to
be unloaded.
Published:
2026-10-28
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
No analysis available yet.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
||||||||||||||||||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
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References
History
Wed, 28 Oct 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the connection remains and the Hyper-V host might continue to send messages or post VMBus interrupts. The problem was introduced in commit 74347a99e73ae ("x86/Hyper-V: Unload vmbus channel in hv panic callback"), in that vmbus_initiate_unload() started checking the current connection state before doing the unload. This commit removed some occurrences where conn_state was forced to DISCONNECTED, but these two remained, apparently due to an oversight at the time. Fix this by not forcing conn_state to DISCONNECTED during VMBus exit, or if a failure occurs when establishing the connection in the first place. Whatever value conn_state has at the time is then read by vmbus_initiate_unload() to determine if there is a connection to be unloaded. | |
| Title | Drivers: hv: Don't reset VMBus connection state on error/exit paths | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-28T10:36:09.383Z
Reserved: 2026-09-25T10:25:14.401Z
Link: CVE-2026-99216
Vulnrichment
No data.
NVD
No data.
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.