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

RDMA/rxe: Fix integer overflow in mr check range() leading to OOB access

mr check range() validates that [iova, iova+length) falls within the registered MR range using wraparound-prone arithmetic:

if (iova < mr->ibmr.iova || iova + length > mr->ibmr.iova + mr->ibmr.length)

A remote peer can craft an RDMA-Write/Read RETH so that iova + length wraps to 0 (e.g. iova=0xfffffffffffffff8, length=8), bypassing the check. rxe mr iova to index() then computes a huge index (int idx, only guarded by WARN ON) and rxe mr copy xarray() dereferences mr->page info[huge], causing an out-of-bounds read/write and a kernel oops that is triggerable by an unauthenticated remote peer.

Rewrite the check in overflow-safe form; the first two clauses guarantee that the subsequent subtractions do not underflow:

if (iova < mr->ibmr.iova || length > mr->ibmr.length || iova - mr->ibmr.iova > mr->ibmr.length - length)

With the fix, mr check range() returns -EINVAL for the crafted iova and the responder reports REMOTE ACCESS ERROR instead of triggering the OOB.