Bug 2439915 (CVE-2026-23174)

Summary: CVE-2026-23174 kernel: nvme-pci: handle changing device dma map requirements
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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OS: Linux   
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Description OSIDB Bzimport 2026-02-14 17:02:53 UTC 
In the Linux kernel, the following vulnerability has been resolved:

nvme-pci: handle changing device dma map requirements

The initial state of dma_needs_unmap may be false, but change to true
while mapping the data iterator. Enabling swiotlb is one such case that
can change the result. The nvme driver needs to save the mapped dma
vectors to be unmapped later, so allocate as needed during iteration
rather than assume it was always allocated at the beginning. This fixes
a NULL dereference from accessing an uninitialized dma_vecs when the
device dma unmapping requirements change mid-iteration.
Comment 1 Alexander B 2026-02-16 18:17:37 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026021427-CVE-2026-23174-0b41@gregkh/T