CVE-2026-43039: net: ti: icssg-prueth: fix missing data copy and wrong recycle in ZC RX dispatch

In the Linux kernel, the following vulnerability has been resolved:

net: ti: icssg-prueth: fix missing data copy and wrong recycle in ZC RX dispatch

emacdispatchskbzc() allocates a new skb via napiallocskb() but never copies the packet data from the XDP buffer into it. The skb is passed up the stack containing uninitialized heap memory instead of the actual received packet, leaking kernel heap contents to userspace.

Copy the received packet data from the XDP buffer into the skb using skbcopytolineardata().

Additionally, remove the skbmarkforrecycle() call since the skb is backed by the NAPI page frag allocator, not pagepool. Marking a non-pagepool skb for recycle causes the free path to return pages to a pagepool that does not own them, corrupting pagepool state.

The non-ZC path (emacrxpacket) does not have these issues because it uses napibuildskb() to wrap the existing pagepool page directly, requiring no copy, and correctly marks for recycle since the page comes from pagepooldevallocpages().