DEBIAN-CVE-2025-21876

Source
https://security-tracker.debian.org/tracker/CVE-2025-21876
Import Source
https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21876.json
JSON Data
https://api.test.osv.dev/v1/vulns/DEBIAN-CVE-2025-21876
Upstream
Published
2025-03-27T15:15:55Z
Modified
2026-08-27T23:05:19Z
Severity
  • 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix suspicious RCU usage Commit ("iommu/vt-d: Allocate DMAR fault interrupts locally") moved the call to enable_drhd_fault_handling() to a code path that does not hold any lock while traversing the drhd list. Fix it by ensuring the dmar_global_lock lock is held when traversing the drhd list. Without this fix, the following warning is triggered: ============================= WARNING: suspicious RCU usage 6.14.0-rc3 #55 Not tainted ----------------------------- drivers/iommu/intel/dmar.c:2046 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 2 locks held by cpuhp/1/23: #0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0 #1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0 stack backtrace: CPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 Not tainted 6.14.0-rc3 #55 Call Trace: dump_stack_lvl+0xb7/0xd0 lockdep_rcu_suspicious+0x159/0x1f0 ? __pfx_enable_drhd_fault_handling+0x10/0x10 enable_drhd_fault_handling+0x151/0x180 cpuhp_invoke_callback+0x1df/0x990 cpuhp_thread_fun+0x1ea/0x2c0 smpboot_thread_fn+0x1f5/0x2e0 ? __pfx_smpboot_thread_fn+0x10/0x10 kthread+0x12a/0x2d0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x4a/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Holding the lock in enable_drhd_fault_handling() triggers a lockdep splat about a possible deadlock between dmar_global_lock and cpu_hotplug_lock. This is avoided by not holding dmar_global_lock when calling iommu_device_register(), which initiates the device probe process.

References

Affected packages

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.12.19-1

Ecosystem specific

{
    "urgency":  "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21876.json"

Debian:14 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.12.19-1

Ecosystem specific

{
    "urgency":  "not yet assigned"
}

Database specific

source
"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21876.json"