CVE-2026-99062

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

vsock/virtio: account only unread bytes in read skb()

After a partial stream receive, rx bytes tracks the unread suffix while buf used and peer credit still cover the whole packet. virtio transport read skb() dequeues that packet but passes pkt len for both counters, underflowing rx bytes.

On a connected CID LOCAL stream with an SK SKB verdict, a 40-byte read from a 100-byte packet made SIOCINQ report -40, an empty recv return ELOOP, and poll report the empty socket readable. After verdict detach, receiving 40 bytes wrapped the counter to zero and hid those queued bytes until one more byte arrived. The fixed run kept the counter balanced and exposed all queued data immediately.

This was found during an LLM-assisted manual source audit of VSOCK receive accounting while re-evaluating virtio transport read skb() after CVE-2024-50169.

Subtract only skb->len minus the VSOCK offset from rx bytes. Retain the full packet length for buf used and peer credit.