In the Linux kernel, the following vulnerability has been resolved:
bridge: mrp: reject zero test interval to avoid OOM panic
br_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied
interval value from netlink without validation. When interval is 0,
usecs_to_jiffies(0) yields 0, causing the delayed work
(br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule
itself with zero delay. This creates a tight loop on system_percpu_wq
that allocates and transmits MRP test frames at maximum rate, exhausting
all system memory and causing a kernel panic via OOM deadlock.
The same zero-interval issue applies to br_mrp_start_in_test_parse()
for interconnect test frames.
Use NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both
IFLA_BRIDGE_MRP_START_TEST_INTERVAL and
IFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the
netlink attribute parsing layer before the value ever reaches the
workqueue scheduling code. This is consistent with how other bridge
subsystems (br_fdb, br_mst) enforce range constraints on netlink
attributes.
bridge: mrp: reject zero test interval to avoid OOM panic
br_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied
interval value from netlink without validation. When interval is 0,
usecs_to_jiffies(0) yields 0, causing the delayed work
(br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule
itself with zero delay. This creates a tight loop on system_percpu_wq
that allocates and transmits MRP test frames at maximum rate, exhausting
all system memory and causing a kernel panic via OOM deadlock.
The same zero-interval issue applies to br_mrp_start_in_test_parse()
for interconnect test frames.
Use NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both
IFLA_BRIDGE_MRP_START_TEST_INTERVAL and
IFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the
netlink attribute parsing layer before the value ever reaches the
workqueue scheduling code. This is consistent with how other bridge
subsystems (br_fdb, br_mst) enforce range constraints on netlink
attributes.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Mon, 13 Apr 2026 13:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: bridge: mrp: reject zero test interval to avoid OOM panic br_mrp_start_test() and br_mrp_start_in_test() accept the user-supplied interval value from netlink without validation. When interval is 0, usecs_to_jiffies(0) yields 0, causing the delayed work (br_mrp_test_work_expired / br_mrp_in_test_work_expired) to reschedule itself with zero delay. This creates a tight loop on system_percpu_wq that allocates and transmits MRP test frames at maximum rate, exhausting all system memory and causing a kernel panic via OOM deadlock. The same zero-interval issue applies to br_mrp_start_in_test_parse() for interconnect test frames. Use NLA_POLICY_MIN(NLA_U32, 1) in the nla_policy tables for both IFLA_BRIDGE_MRP_START_TEST_INTERVAL and IFLA_BRIDGE_MRP_START_IN_TEST_INTERVAL, so zero is rejected at the netlink attribute parsing layer before the value ever reaches the workqueue scheduling code. This is consistent with how other bridge subsystems (br_fdb, br_mst) enforce range constraints on netlink attributes. | |
| Title | bridge: mrp: reject zero test interval to avoid OOM panic | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-04-13T13:40:24.594Z
Reserved: 2026-03-09T15:48:24.088Z
Link: CVE-2026-31420
No data.
Status : Received
Published: 2026-04-13T14:16:11.617
Modified: 2026-04-13T14:16:11.617
Link: CVE-2026-31420
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.