net: cap skb->queue_mapping when the tx queue is picked
In the Linux kernel, the following vulnerability has been resolved: net: cap skb->queue_mapping when the tx queue is picked skbedit can set skb->queue_mapping and raise the per-CPU skip_txqueue flag so __dev_queue_xmit() honours the mapping. __dev_queue_xmit() cleared the flag before sch_handle_egress() and only read it afterwards, so the flag was not confined to the xmit that set it: a nested xmit (mirred redirect or mirror, or a drop after skbedit) could set the flag and the outer xmit would consume it for an skb that never went through skbedit. A forwarded packet still carries the ingress NIC's rx_queue + 1 in skb->queue_mapping, so the outer device then indexes its tx queue state with that stale value. Taprio's child array q->qdiscs[] is sized to the device's queue count, so taprio_enqueue() indexes past its allocation and dereferences the result as a struct Qdisc *. We (ab)use the skb->nf_skip_egress which means "skip netfilter egress for this packet" to tag to "am I in tc egress?". Despite the overload I dont see it as a conflict since the marker is set only around the single sch_handle_egress() call and ingress path is guarded by tc_at_ingress. I will send a followup(net-next) patch once this hits net-next to rename the skb->nf_skip_egress bit/flag to skb->skip_egress Arm the flag only from the egress classifier that can use it: raise skip_txqueue from tcf_skbedit_act() only when it runs inside sch_handle_egress(), thanks to skb->nf_skip_egress. An egress qdisc classif
CVE-2026-98797
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98797
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2f1e85b1aee459b7d0fd981839042c6a38ffaf0c",
"lessThan": "c6ec35c8267c84c2094cb485db20c06384fc2bcc",
"versionType": "git"
},
{
"status": "affected",
"version": "2f1e85b1aee459b7d0fd981839042c6a38ffaf0c",
"lessThan": "2f581814e4e3ea6a5e98f49813dc4c68444a0c4a",
"versionType": "git"
},
{
"status": "affected",
"version": "2f1e85b1aee459b7d0fd981839042c6a38ffaf0c",
"lessThan": "f99de42f5c6f8d088063817dad82c3334e87c570",
"versionType": "git"
},
{
"status": "affected",
"version": "2f1e85b1aee459b7d0fd981839042c6a38ffaf0c",
"lessThan": "ea4d4b5dddb5121e64f56fd8e0720bd8b447b63d",
"versionType": "git"
}
],
"programFiles": [
"include/linux/netfilter_netdev.h",
"include/linux/rtnetlink.h",
"include/linux/skbuff.h",
"include/net/sch_generic.h",
"net/core/dev.c",
"net/sched/act_skbedit.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.19"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.19",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.56",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.10",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/linux/netfilter_netdev.h",
"include/linux/rtnetlink.h",
"include/linux/skbuff.h",
"include/net/sch_generic.h",
"net/core/dev.c",
"net/sched/act_skbedit.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98797
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38721 · Revision 1
- Added to Heist Feed
- Publisher date