boxscore/security
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Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2022-49872MEDIUM
Linux Linux — net: gso: fix panic on frag_list with mixed head alloc types
  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  N  N  H    5.5   .0048   39.8     —
AFFECTED
  Product  Versions                                    Fixed
  Linux    162a5a8c3aff15c449e6b38355cdf80ab4f77a5a –  —
  Linux    5.3 –                                       4.9.334
TIMELINE
  May 1   Reserved by Linux
  May 1   Published (CNA: Linux)
  Aug 4   RESCORED — CVE-2022-49872 (Linux). CVSS 7.5 → 5.5 (NVD).
CNA: Linux · CVSS v3.1 · 8 references · NVD status: Modified

Description

In the Linux kernel, the following vulnerability has been resolved: net: gso: fix panic on frag_list with mixed head alloc types Since commit 3dcbdb134f32 ("net: gso: Fix skb_segment splat when splitting gso_size mangled skb having linear-headed frag_list"), it is allowed to change gso_size of a GRO packet. However, that commit assumes that "checking the first list_skb member suffices; i.e if either of the list_skb members have non head_frag head, then the first one has too". It turns out this assumption does not hold. We've seen BUG_ON being hit in skb_segment when skbs on the frag_list had differing head_frag with the vmxnet3 driver. This happens because __netdev_alloc_skb and __napi_alloc_skb can return a skb that is page backed or kmalloced depending on the requested size. As the result, the last small skb in the GRO packet can be kmalloced. There are three different locations where this can be fixed: (1) We could check head_frag in GRO and not allow GROing skbs with different head_frag. However, that would lead to performance regression on normal forward paths with unmodified gso_size, where !head_frag in the last packet is not a problem. (2) Set a flag in bpf_skb_net_grow and bpf_skb_net_shrink indicating that NETIF_F_SG is undesirable. That would need to eat a bit in sk_buff. Furthermore, that flag can be unset when all skbs on the frag_list are page backed. To retain good performance, bpf_skb_net_grow/shrink would have to walk the frag_list. (3) Walk the frag_list in skb_segment when determining whether NETIF_F_SG should be cleared. This of course slows things down. This patch implements (3). To limit the performance impact in skb_segment, the list is walked only for skbs with SKB_GSO_DODGY set that have gso_size changed. Normal paths thus will not hit it. We could check only the last skb but since we need to walk the whole list anyway, let's stay on the safe side.

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
May 1, 2025ReservedReserved by Linux
May 1, 2025PublishedPublished (CNA: Linux)
August 4, 2026RESCOREDRESCORED — CVE-2022-49872 (Linux). CVSS 7.5 → 5.5 (NVD).

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux162a5a8c3aff15c449e6b38355cdf80ab4f77a5a
LinuxLinux5.34.9.334

References (8)

Related

Authoritative record: CVE-2022-49872 at cve.org

Vendors: linux

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2022-49872 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.