In the Linux kernel, the following vulnerability has been resolved: RDMA/umem: Fix truncation for block sizes >= 4G When the iommu is used the linearization of the mapping can give a single block that is very large split across multiple SG entries. When __rdma_block_iter_next() reassembles the split SG entries it is overflowing the 32 bit stack values and computed the wrong DMA addresses for blocks after the truncation. Use the right types to hold DMA addresses.

A flaw was found in the Linux kernel's RDMA/umem component. When the IOMMU (Input/Output Memory Management Unit) is used, a very large memory block can be split across multiple scatter-gather (SG) entries. During the reassembly of these split SG entries, an issue with truncation for block sizes greater than or equal to 4 gigabytes (4G) can lead to an overflow of 32-bit stack values. This results in the computation of incorrect DMA (Direct Memory Access) addresses, potentially causing data corruption or system instability.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53133 https://nvd.nist.gov/vuln/detail/CVE-2026-53133 https://lore.kernel.org/linux-cve-announce/2026062542-CVE-2026-53133-de02@gregkh/T