Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Zero rpc_gss_wire_cred at svcauth_gss_decode_credbody() entry svcauth_gss_decode_credbody() writes the caller's rpc_gss_wire_cred field by field and assigns gc_ctx.len only on the success tail. The caller storage is svcdata->clcred, which lives in the per-svc_rqst gss_svc_data and is reused across requests. Early decode failures leave partially decoded state mixed with residue from the prior request. The trailing body_len tightness check is the sharpest case: xdr_stream_decode_opaque_inline() has already written gc_ctx.data with a borrowed inline pointer into the current request's XDR pages, but gc_ctx.len retains its prior value. Once the request pages are released the pooled clcred carries a dangling pointer paired with a stale length. Zero the caller's rpc_gss_wire_cred at function entry so that every early-return path leaves a deterministic all-zero cred. On the trailing tightness-check path, gc_ctx.len is now zero instead of stale, which neuters length-driven consumers such as gss_svc_searchbyctx() that would otherwise walk the dangling data pointer.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected b0bc53470d1af01f62a0fe2d405cf56477804863 before 56b29d62017c7dd1718d060dd5b3a2ce61095d0c; affected b0bc53470d1af01f62a0fe2d405cf56477804863 before 0e18641708eaa8bc3c1ff338cd844aeadbd52bac; affected b0bc53470d1af01f62a0fe2d405cf56477804863 before e0778464049b0238f2915a40007a4154f86cf351; affected b0bc53470d1af01f62a0fe2d405cf56477804863 before 0fa8a8acae57e6373962741d5b06d13f44aba6a9; affected b0bc53470d1af01f62a0fe2d405cf56477804863 before 11539e8fcce0b0af062ae5fecf7b3676c2f7aeed |
| Linux / Linux | affected 6.3; unaffected 0 before 6.3; unaffected 6.6.157 through 6.6.*; unaffected 6.12.109 through 6.12.*; unaffected 6.18.50 through 6.18.*; unaffected 7.2.4 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/56b29d62017c7dd1718d060dd5b3a2ce61095d0c
- https://git.kernel.org/stable/c/0e18641708eaa8bc3c1ff338cd844aeadbd52bac
- https://git.kernel.org/stable/c/e0778464049b0238f2915a40007a4154f86cf351
- https://git.kernel.org/stable/c/0fa8a8acae57e6373962741d5b06d13f44aba6a9
- https://git.kernel.org/stable/c/11539e8fcce0b0af062ae5fecf7b3676c2f7aeed