CVE-2026-43211
HIGH SEVERITYCVSS Score & Metrics
Base Score
7.8 / 10
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved:
PCI: Fix pci_slot_trylock() error handling
Commit a4e772898f8b ("PCI: Add missing bridge lock to pci_bus_lock()")
delegates the bridge device's pci_dev_trylock() to pci_bus_trylock() in
pci_slot_trylock(), but it forgets to remove the corresponding
pci_dev_unlock() when pci_bus_trylock() fails.
Before a4e772898f8b, the code did:
if (!pci_dev_trylock(dev)) /* <- lock bridge device */
goto unlock;
if (dev->subordinate) {
if (!pci_bus_trylock(dev->subordinate)) {
pci_dev_unlock(dev); /* <- unlock bridge device */
goto unlock;
}
}
After a4e772898f8b the bridge-device lock is no longer taken, but the
pci_dev_unlock(dev) on the failure path was left in place, leading to the
bug.
This yields one of two errors:
1. A warning that the lock is being unlocked when no one holds it.
2. An incorrect unlock of a lock that belongs to another thread.
Fix it by removing the now-redundant pci_dev_unlock(dev) on the failure
path.
[Same patch later posted by Keith at
https://patch.msgid.link/20260116184150.3013258-1-kbusch@meta.com]
PCI: Fix pci_slot_trylock() error handling
Commit a4e772898f8b ("PCI: Add missing bridge lock to pci_bus_lock()")
delegates the bridge device's pci_dev_trylock() to pci_bus_trylock() in
pci_slot_trylock(), but it forgets to remove the corresponding
pci_dev_unlock() when pci_bus_trylock() fails.
Before a4e772898f8b, the code did:
if (!pci_dev_trylock(dev)) /* <- lock bridge device */
goto unlock;
if (dev->subordinate) {
if (!pci_bus_trylock(dev->subordinate)) {
pci_dev_unlock(dev); /* <- unlock bridge device */
goto unlock;
}
}
After a4e772898f8b the bridge-device lock is no longer taken, but the
pci_dev_unlock(dev) on the failure path was left in place, leading to the
bug.
This yields one of two errors:
1. A warning that the lock is being unlocked when no one holds it.
2. An incorrect unlock of a lock that belongs to another thread.
Fix it by removing the now-redundant pci_dev_unlock(dev) on the failure
path.
[Same patch later posted by Keith at
https://patch.msgid.link/20260116184150.3013258-1-kbusch@meta.com]
Vulnerability Details
Published Date
Last Modified
CWE ID
CWE-667
Source
NVD
Vendor
Linux
Product
Linux
External References
- https://git.kernel.org/stable/c/0425aaf20b407d2f2cf3bf469808e4a35f9abb8b
- https://git.kernel.org/stable/c/8b08ea9690b212b7bf7f12414039259cf34b1aa0
- https://git.kernel.org/stable/c/9368d1ee62829b08aa31836b3ca003803caf0b72
- https://git.kernel.org/stable/c/943ed56606a7ab2fe5a99cad572dd17d484310c7
- https://git.kernel.org/stable/c/a19b61fdb958ffadbba85b43c991eb9fc70c1c1c
- https://git.kernel.org/stable/c/bd435f4b738130d732ef64e0e57e45185f77165d
- https://git.kernel.org/stable/c/ebb27b7399ab8b9eb1f792b329aa5f6250c590d4
- https://git.kernel.org/stable/c/fbe06a3058114bf95a17a4941b205f4b321c6f0a
Discussion (0)
Add Comment
No comments yet. Be the first!