cve/2024/CVE-2024-49948.md
2025-09-29 21:09:30 +02:00

1.3 KiB

CVE-2024-49948

Description

In the Linux kernel, the following vulnerability has been resolved:net: add more sanity checks to qdisc_pkt_len_init()One path takes care of SKB_GSO_DODGY, assumingskb->len is bigger than hdr_len.virtio_net_hdr_to_skb() does not fully dissect TCP headers,it only make sure it is at least 20 bytes.It is possible for an user to provide a malicious 'GSO' packet,total length of 80 bytes.- 20 bytes of IPv4 header- 60 bytes TCP header- a small gso_size like 8virtio_net_hdr_to_skb() would declare this packet as a normalGSO packet, because it would see 40 bytes of payload,bigger than gso_size.We need to make detect this case to not underflowqdisc_skb_cb(skb)->pkt_len.

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