drop_monitor: use timer_shutdown_sync() to prevent timer rearming during teardown
In the Linux kernel, the following vulnerability has been resolved: drop_monitor: use timer_shutdown_sync() to prevent timer rearming during teardown In drop_monitor teardown paths (net_dm_trace_off_set(), net_dm_hw_monitor_stop(), and error unwind paths in net_dm_trace_on_set() and net_dm_hw_monitor_start()), per-CPU timers are stopped using timer_delete_sync() followed by cancel_work_sync(). However, there is a circular dependency between send_timer and dm_alert_work: 1) sched_send_work() (timer callback) schedules dm_alert_work. 2) send_dm_alert() / net_dm_hw_summary_work() calls reset_per_cpu_data() or net_dm_hw_reset_per_cpu_data(). 3) If memory allocation fails under memory pressure in the reset function, it re-arms the timer via mod_timer(&data->send_timer, ...). If dm_alert_work is running concurrently while timer_delete_sync() executes on another CPU, an allocation failure in the worker will re-arm the timer after timer_delete_sync() has already returned. Once cancel_work_sync() completes and module_put() is called, the timer remains active in the timer wheel. If the module is then unloaded, the timer will fire and execute sched_send_work() in freed memory, triggering a kernel panic / use-after-free. Switch from timer_delete_sync() to timer_shutdown_sync(). This guarantees that any in-flight timer handler has finished and prevents subsequent re-arming attempts from running workers from succeeding. When monitoring is restarted later, timer_setup() is invoked, which cl
CVE-2026-98286
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98286
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "9398e9c0b1d44eeb700e9e766c02bcc765c82570",
"lessThan": "9616b0c67fbd8cc0b49de7b26cdf2ab33747c80e",
"versionType": "git"
},
{
"status": "affected",
"version": "9398e9c0b1d44eeb700e9e766c02bcc765c82570",
"lessThan": "bda4d9525fb91a2388ee09669421b8d505290864",
"versionType": "git"
},
{
"status": "affected",
"version": "9398e9c0b1d44eeb700e9e766c02bcc765c82570",
"lessThan": "c391a40f71886b28c082b47270f0e856fa3e1150",
"versionType": "git"
},
{
"status": "affected",
"version": "2514c7ad115e762562c7bdd58bb1ab3425a98245",
"versionType": "git"
},
{
"status": "affected",
"version": "439b1164da3612ec7e186e1dc314471e7190bfc7",
"versionType": "git"
},
{
"status": "affected",
"version": "5.10.27",
"lessThan": "5.11",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.11.11",
"lessThan": "5.12",
"versionType": "semver"
}
],
"programFiles": [
"net/core/drop_monitor.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.54",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.8",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/core/drop_monitor.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98286
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38364 · Revision 1
- Added to Heist Feed
- Publisher date