Bug 2492822 (CVE-2026-53190)

Summary: CVE-2026-53190 kernel: drm/virtio: fix dma_fence refcount leak on error in virtio_gpu_dma_fence_wait()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
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OS: Linux   
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Description OSIDB Bzimport 2026-06-25 10:07:35 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/virtio: fix dma_fence refcount leak on error in virtio_gpu_dma_fence_wait()

dma_fence_unwrap_for_each() internally calls dma_fence_unwrap_first()
which does cursor->chain = dma_fence_get(head), taking an extra
reference. On normal loop completion, dma_fence_unwrap_next()
releases this via dma_fence_chain_walk() -> dma_fence_put().

When virtio_gpu_do_fence_wait() fails and the function returns early
from inside the loop, the cursor->chain reference is never released.
This is the only caller in the entire kernel that does an early return
inside dma_fence_unwrap_for_each.

Add dma_fence_put(itr.chain) before the early return.
Comment 1 Mauro Matteo Cascella 2026-06-29 13:58:39 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062557-CVE-2026-53190-819e@gregkh/T