Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject exclusive maps as inner maps in map-in-map An exclusive map (created with excl_prog_hash) is bound to a single program by hash: check_map_prog_compatibility() refuses to load any program whose digest does not match map->excl_prog_sha. That check only runs for maps a program references directly, i.e. its used_maps. A map reached at runtime through a map-of-maps is never in used_maps, and bpf_map_meta_equal() does not consider excl_prog_sha, so an exclusive map can be inserted into a non-exclusive outer map and then looked up and mutated by an unrelated program, bypassing the exclusivity guarantee. For the signed loader this defeats the metadata map exclusivity check added in the signed loader: the cached map->sha[] is validated against the signed hash while another program on a hostile host rewrites the frozen map's contents through the outer map.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected baefdbdf6812e120c9fba9cfb101d3656f478026 before 3a0f73d27a8d379a8852a378b3c3208143e3b3b2; affected baefdbdf6812e120c9fba9cfb101d3656f478026 before 7c58ace08f180f8e249e714d1623388362f9d807; affected baefdbdf6812e120c9fba9cfb101d3656f478026 before 9a3c3c49c333760c8944dadacbe114c1884546ef |
| Linux / Linux | affected 6.18; unaffected 0 before 6.18; unaffected 6.18.40 through 6.18.*; unaffected 7.1.5 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.