CVE-2026-53235

Description

In the Linux kernel, the following vulnerability has been resolved: net: add pskb_may_pull() to skb_gro_receive_list() skb_gro_receive_list() calls skb_pull(skb, skb_gro_offset(skb)) without first ensuring the data is in the linear area via pskb_may_pull(). When the skb arrives via napi_gro_frags(), skb_headlen can be 0 (all data in page fragments) while skb_gro_offset is non-zero (after IP+TCP header parsing). The skb_pull() then decrements skb->len by skb_gro_offset but skb->data_len stays unchanged, hitting BUG_ON(skb->len < skb->data_len) in __skb_pull(). The UDP fraglist GRO path already contains this guard at udp_offload.c:749. Adding it to skb_gro_receive_list() itself provides centralized protection for all callers (TCP, UDP, and any future protocols), and ensures the precondition of skb_pull() is satisfied before it is called. On pskb_may_pull() failure, set NAPI_GRO_CB(skb)->flush = 1 so the skb is not held as a new GRO head and is instead delivered through the normal receive path, matching the UDP handling.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://git.kernel.org/stable/c/9e636c995b7beeb74ea882968248752821c244c4 ↗
• https://git.kernel.org/stable/c/0cde3a004119db637b401c54e77536e4145fc0b4 ↗
• https://git.kernel.org/stable/c/848571dcbbbea7ba44dd4f7ebe1fbb274afe08ac ↗
• https://git.kernel.org/stable/c/f2bb3434544454099a5b6dec213567267b05d79d ↗