In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject fragmented frames in devmap
Devmap broadcast redirects clone the packet for all but the last destination.
For native XDP, that clone path copies only the linear xdp_frame data, while fragmented frames keep skb_shared_info in tailroom outside the linear area. Cloning such a frame leaves XDP_FLAGS_HAS_FRAGS set but without valid frag metadata, and the later free path can interpret uninitialized tail data as skb_shared_info, leading to an out-of-bounds access during frame return.
Reject fragmented native XDP frames in dev_map_enqueue_clone().
Add the same restriction to the generic XDP clone path in dev_map_redirect_clone(). Generic XDP represents fragmented packets as nonlinear skbs, and rejecting them here keeps clone-based broadcast support aligned between native and generic XDP.
References
- https://git.kernel.org/stable/c/07a4c11ee8ef4abcb39d922e9e410ae269671cdf
- https://git.kernel.org/stable/c/47baddc856ae7e93a565dd9deeb797999b179466
- https://git.kernel.org/stable/c/51d07c12ca411e692c424ecdabf077f1e61a61be
- https://git.kernel.org/stable/c/a9bb2d9c798cb62a4050a991c27b752770c33afe
- https://git.kernel.org/stable/c/aa496720618f1a6054f1c870bf10b4f6c99bf656
- https://git.kernel.org/stable/c/bccbab36ff228e0825eb85d9b0f9b8434cd0a399
- https://git.kernel.org/stable/c/c5b4f5efcb55c1af3fe44ff712d31b7fb098a831