FKIE_CVE-2026-72046
Vulnerability from fkie_nvd - Published: 2026-08-15 06:21 - Updated: 2026-08-17 06:18
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved:
gve: fix header buffer corruption with header-split and HW-GRO
The DQO RX datapath programs a per-buffer-queue-descriptor
header_buf_addr at post time and reads the split header back at
completion time. Both the post and the read currently index the
header buffer by queue position rather than by the buffer's identity:
- post (gve_rx_post_buffers_dqo): header_buf_addr is computed from
bufq->tail
- read (gve_rx_dqo): the header is read from desc_idx (the completion
queue head index)
This relies on the buffer-queue index and the completion-queue index
being equal for the start of every packet, i.e. on the device consuming
posted buffers and returning completions in the exact same order. That
assumption does not hold once HW-GRO is enabled with multiple
flows: coalesced segments are accepted and completed in an order that
may differ from the order buffers were posted, and segments from
different flows may interleave.
That results in two problems:
1. Wrong header slot on read. Because the read offset is derived from
the completion index (desc_idx) while the device wrote the header to
the address programmed for the buffer's buf_id, the driver can copy
a header belonging to a different packet. This shows up as
throughput drop (about 30% drop and large numbers of TCP
retransmissions) with header-split and HW-GRO both enabled and many
streams.
2. Header buffer reused while still owned by the device. The driver
advances bufq->head by one per completion and re-posts buffers based
on that. Arrival of N RX completions only guarantees that at least N
RX buffer descriptors have been read by the device. It does not
guarantee that the device has relinquished the ownership of all the
buffers corresponding to those N descriptors. With out-of-order
completions (e.g. the completion for a packet copied into buffer N
arrives before the completion for a packet copied into buffer N-1),
the driver can re-post and overwrite a header buffer that the device
is still going to write into, corrupting the header of a packet
whose completion has not yet been processed.
Fix both issues by indexing the header buffer by buf_id on both the post
and read paths. Reading from buf_id's slot is therefore always correct
regardless of completion ordering (fixes problem 1).
Indexing by buf_id also ties each header slot to the lifetime of its
buffer state. A buffer state is only returned to the free/recycle lists
when its own completion (buf_id) is processed, so its header slot can
only be re-posted after the device is done with it. This makes header
slot reuse safe under out-of-order completions (fixes problem 2).
Allocate (gve_rx_alloc_hdr_bufs) and free (gve_rx_free_hdr_bufs) the
header buffers based on num_buf_states to match the buf_id indexing.
References
Impacted products
| Vendor | Product | Version |
|---|
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"drivers/net/ethernet/google/gve/gve_rx_dqo.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "84d3753d4bf284ef770ead6dee2270aaabb3ef41",
"status": "affected",
"version": "5e37d8254e7f551dda62e7590e819d69c7491845",
"versionType": "git"
},
{
"lessThan": "35267819b25074084130b6a7be18bbaf44d3ae74",
"status": "affected",
"version": "5e37d8254e7f551dda62e7590e819d69c7491845",
"versionType": "git"
},
{
"lessThan": "9f8e7f59b0c2f466be74bd923726b0f5496c27ad",
"status": "affected",
"version": "5e37d8254e7f551dda62e7590e819d69c7491845",
"versionType": "git"
},
{
"lessThan": "d676c9a73bdcd8237425dbb826f2bd1a25c36e40",
"status": "affected",
"version": "5e37d8254e7f551dda62e7590e819d69c7491845",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"drivers/net/ethernet/google/gve/gve_rx_dqo.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.9"
},
{
"lessThan": "6.9",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.101",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ngve: fix header buffer corruption with header-split and HW-GRO\n\nThe DQO RX datapath programs a per-buffer-queue-descriptor\nheader_buf_addr at post time and reads the split header back at\ncompletion time. Both the post and the read currently index the\nheader buffer by queue position rather than by the buffer\u0027s identity:\n\n - post (gve_rx_post_buffers_dqo): header_buf_addr is computed from\n bufq-\u003etail\n - read (gve_rx_dqo): the header is read from desc_idx (the completion\n queue head index)\n\nThis relies on the buffer-queue index and the completion-queue index\nbeing equal for the start of every packet, i.e. on the device consuming\nposted buffers and returning completions in the exact same order. That\nassumption does not hold once HW-GRO is enabled with multiple\nflows: coalesced segments are accepted and completed in an order that\nmay differ from the order buffers were posted, and segments from\ndifferent flows may interleave.\n\nThat results in two problems:\n\n1. Wrong header slot on read. Because the read offset is derived from\n the completion index (desc_idx) while the device wrote the header to\n the address programmed for the buffer\u0027s buf_id, the driver can copy\n a header belonging to a different packet. This shows up as\n throughput drop (about 30% drop and large numbers of TCP\n retransmissions) with header-split and HW-GRO both enabled and many\n streams.\n\n2. Header buffer reused while still owned by the device. The driver\n advances bufq-\u003ehead by one per completion and re-posts buffers based\n on that. Arrival of N RX completions only guarantees that at least N\n RX buffer descriptors have been read by the device. It does not\n guarantee that the device has relinquished the ownership of all the\n buffers corresponding to those N descriptors. With out-of-order\n completions (e.g. the completion for a packet copied into buffer N\n arrives before the completion for a packet copied into buffer N-1),\n the driver can re-post and overwrite a header buffer that the device\n is still going to write into, corrupting the header of a packet\n whose completion has not yet been processed.\n\nFix both issues by indexing the header buffer by buf_id on both the post\nand read paths. Reading from buf_id\u0027s slot is therefore always correct\nregardless of completion ordering (fixes problem 1).\n\nIndexing by buf_id also ties each header slot to the lifetime of its\nbuffer state. A buffer state is only returned to the free/recycle lists\nwhen its own completion (buf_id) is processed, so its header slot can\nonly be re-posted after the device is done with it. This makes header\nslot reuse safe under out-of-order completions (fixes problem 2).\n\nAllocate (gve_rx_alloc_hdr_bufs) and free (gve_rx_free_hdr_bufs) the\nheader buffers based on num_buf_states to match the buf_id indexing."
}
],
"id": "CVE-2026-72046",
"lastModified": "2026-08-17T06:18:02.577",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 3.9,
"impactScore": 5.9,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
}
]
},
"published": "2026-08-15T06:21:13.810",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/35267819b25074084130b6a7be18bbaf44d3ae74"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/84d3753d4bf284ef770ead6dee2270aaabb3ef41"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/9f8e7f59b0c2f466be74bd923726b0f5496c27ad"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/d676c9a73bdcd8237425dbb826f2bd1a25c36e40"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Received"
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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