In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix seg fault in rxecompqueue_pkt
In rxecompqueuepkt() an incoming response packet skb is enqueued to the resppkts queue and then a decision is made whether to run the completer task inline or schedule it. Finally the skb is dereferenced to bump a 'hw' performance counter. This is wrong because if the completer task is already running in a separate thread it may have already processed the skb and freed it which can cause a seg fault. This has been observed infrequently in testing at high scale.
This patch fixes this by changing the order of enqueuing the packet until after the counter is accessed.