smb: client: fix potential UAF in smb2_close_cached_fid()
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in smb2_close_cached_fid() find_or_create_cached_dir() could grab a new reference after kref_put() had seen the refcount drop to zero but before cfid_list_lock is acquired in smb2_close_cached_fid(), leading to use-after-free. Switch to kref_put_lock() so cfid_release() is called with cfid_list_lock held, closing that gap.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in smb2_close_cached_fid() find_or_create_cached_dir() could grab a new reference after kref_put() had seen the refcount drop to zero but before cfid_list_lock is acquired in smb2_close_cached_fid(), leading to use-after-free. Switch to kref_put_lock() so cfid_release() is called with cfid_list_lock held, closing that gap.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/065bd62412271a2d734810dd50336cae88c54427
- https://git.kernel.org/stable/c/734e99623c5b65bf2c03e35978a0b980ebc3c2f8
- https://git.kernel.org/stable/c/bdb596ceb4b7c3f28786a33840263728217fbcf5
- https://git.kernel.org/stable/c/cb52d9c86d70298de0ab7c7953653898cbc0efd6
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40328.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-40328