In the Linux kernel, the following vulnerability has been resolved:
igc: fix PTM cycle trigger logic
Writing to clear the PTM status 'valid' bit while the PTM cycle is
triggered results in unreliable PTM operation. To fix this, clear the
PTM 'trigger' and status after each PTM transaction.
The issue can be reproduced with the following:
$ sudo phc2sys -R 1000 -O 0 -i tsn0 -m
Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to
quickly reproduce the issue.
PHC2SYS exits with:
"ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction
fails
This patch also fixes a hang in igc_probe() when loading the igc
driver in the kdump kernel on systems supporting PTM.
The igc driver running in the base kernel enables PTM trigger in
igc_probe(). Therefore the driver is always in PTM trigger mode,
except in brief periods when manually triggering a PTM cycle.
When a crash occurs, the NIC is reset while PTM trigger is enabled.
Due to a hardware problem, the NIC is subsequently in a bad busmaster
state and doesn't handle register reads/writes. When running
igc_probe() in the kdump kernel, the first register access to a NIC
register hangs driver probing and ultimately breaks kdump.
With this patch, igc has PTM trigger disabled most of the time,
and the trigger is only enabled for very brief (10 - 100 us) periods
when manually triggering a PTM cycle. Chances that a crash occurs
during a PTM trigger are not 0, but extremely reduced.
Metrics
Affected Vendors & Products
References
History
Wed, 16 Jul 2025 13:45:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
epss
|
epss
|
Sat, 10 May 2025 02:30:00 +0000
Type | Values Removed | Values Added |
---|---|---|
References |
| |
Metrics |
threat_severity
|
cvssV3_1
|
Fri, 09 May 2025 07:00:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Description | In the Linux kernel, the following vulnerability has been resolved: igc: fix PTM cycle trigger logic Writing to clear the PTM status 'valid' bit while the PTM cycle is triggered results in unreliable PTM operation. To fix this, clear the PTM 'trigger' and status after each PTM transaction. The issue can be reproduced with the following: $ sudo phc2sys -R 1000 -O 0 -i tsn0 -m Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to quickly reproduce the issue. PHC2SYS exits with: "ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction fails This patch also fixes a hang in igc_probe() when loading the igc driver in the kdump kernel on systems supporting PTM. The igc driver running in the base kernel enables PTM trigger in igc_probe(). Therefore the driver is always in PTM trigger mode, except in brief periods when manually triggering a PTM cycle. When a crash occurs, the NIC is reset while PTM trigger is enabled. Due to a hardware problem, the NIC is subsequently in a bad busmaster state and doesn't handle register reads/writes. When running igc_probe() in the kdump kernel, the first register access to a NIC register hangs driver probing and ultimately breaks kdump. With this patch, igc has PTM trigger disabled most of the time, and the trigger is only enabled for very brief (10 - 100 us) periods when manually triggering a PTM cycle. Chances that a crash occurs during a PTM trigger are not 0, but extremely reduced. | |
Title | igc: fix PTM cycle trigger logic | |
References |
|
|

Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-26T05:22:48.769Z
Reserved: 2025-04-16T04:51:23.960Z
Link: CVE-2025-37875

No data.

Status : Awaiting Analysis
Published: 2025-05-09T07:16:08.670
Modified: 2025-05-12T17:32:32.760
Link: CVE-2025-37875


No data.