GHSA-p68h-c56f-p3v6MediumCVSS 5.5
In the Linux kernel, the following vulnerability has been resolved: smb: client: split...
🔗 CVE IDs covered (1)
📋 Description
In the Linux kernel, the following vulnerability has been resolved:
smb: client: split cached_fid bitfields to avoid shared-byte RMW races
is_open, has_lease and on_list are stored in the same bitfield byte in
struct cached_fid but are updated in different code paths that may run
concurrently. Bitfield assignments generate byte read–modify–write
operations (e.g. orb $mask, addr on x86_64), so updating one flag can
restore stale values of the others.
A possible interleaving is: CPU1: load old byte (has_lease=1, on_list=1) CPU2: clear both flags (store 0) CPU1: RMW store (old | IS_OPEN) -> reintroduces cleared bits
To avoid this class of races, convert these flags to separate bool fields.
🔗 References (9)
- https://nvd.nist.gov/vuln/detail/CVE-2026-23230
- https://git.kernel.org/stable/c/3eaa22d688311c708b73f3c68bc6d0c8e3f0f77a
- https://git.kernel.org/stable/c/4386f6af8aaedd0c5ad6f659b40cadcc8f423828
- https://git.kernel.org/stable/c/4cfa4c37dcbcfd70866e856200ed8a2894cac578
- https://git.kernel.org/stable/c/c4b9edd55987384a1f201d3d07ff71e448d79c1b
- https://git.kernel.org/stable/c/569fecc56bfe4df66f05734d67daef887746656b
- https://git.kernel.org/stable/c/ec306600d5ba7148c9dbf8f5a8f1f5c1a044a241
- https://cert-portal.siemens.com/productcert/html/ssa-253495.html
- https://github.com/advisories/GHSA-p68h-c56f-p3v6