CVE-2026-97421: RDMA/umem: Be careful about boundary conditions in ib_umem_find_best_pgsz()
In the Linux kernel, the following vulnerability has been resolved:
RDMA/umem: Be careful about boundary conditions in ibumemfindbestpgsz()
Several corner cases, especially important on 32 bits:
- umem->iova is u64, the function argument should pass in u64 or iova will be truncated - Check that the length is not too large for the iova - Check that lengths > 4G don't overflow the GENMASK
Affected Software
Event History
Frequently Asked Questions
Which systems should be prioritized for remediation?
32-bit Linux systems should be prioritized, as the affected boundary-condition cases are especially important there. Systems using RDMA user-memory mappings are the relevant exposure area.
What conditions are involved in the flaw?
The affected code can mishandle a 64-bit IOVA if it is truncated, lengths that are too large for the IOVA, and lengths greater than 4 GB that can overflow the GENMASK calculation.