Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
lockd: Plug nlm_file refcount leak on cached nlm_do_fopen() failure
The cached-file path in nlm_lookup_file() reaches the found: label unconditionally, even when nlm_do_fopen() fails. At that label *result and file->f_count are updated before the error is returned. The wrappers nlm3svc_lookup_file() and nlm4svc_lookup_file() then bail out of their switch without copying *result back to their caller, so the proc handler’s local nlm_file pointer remains NULL and the cleanup path skips nlm_release_file(). The f_count increment is never released, and nlm_traverse_files() can no longer reap the file because its refcount never returns to zero between requests.
Short-circuit the cached path so neither *result nor f_count is touched when nlm_do_fopen() fails on a hashed nlm_file.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Debian 10 ELS , Debian 11 ELS , TuxCare 9.6 ESU
- Affected packages:
- linux @ 5.10.259 (+3 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Amazon Linux 2023 | Planned | — |
| Oracle Linux 9 UEK 7 | Planned | — |