CVE-2026-43211
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.11%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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]
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.11% probability · 1th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-667
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0425aaf20b407d2f2cf3bf469808e4a35f9abb8bPatch
- https://git.kernel.org/stable/c/8b08ea9690b212b7bf7f12414039259cf34b1aa0Patch
- https://git.kernel.org/stable/c/9368d1ee62829b08aa31836b3ca003803caf0b72Patch
- https://git.kernel.org/stable/c/943ed56606a7ab2fe5a99cad572dd17d484310c7Patch
- https://git.kernel.org/stable/c/a19b61fdb958ffadbba85b43c991eb9fc70c1c1cPatch
- https://git.kernel.org/stable/c/bd435f4b738130d732ef64e0e57e45185f77165dPatch
- https://git.kernel.org/stable/c/ebb27b7399ab8b9eb1f792b329aa5f6250c590d4Patch
- https://git.kernel.org/stable/c/fbe06a3058114bf95a17a4941b205f4b321c6f0aPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.