net/sched: act_ct: don't WARN on benign flow_offload_alloc() failure
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: don't WARN on benign flow_offload_alloc() failure flow_offload_alloc() returns NULL when the conntrack entry is dying (e.g. raced with a conntrack flush) or when the GFP_ATOMIC allocation fails; both are expected under load and neither is a kernel bug. This path runs from softirq on every committed packet, so with panic_on_warn=1 an unprivileged user can panic the box just by racing a conntrack flush against a `tc ... action ct commit` classifier. Reproduced with a custom repro under QEMU: a small, fixed set of UDP flows through `tc filter ... action ct commit` on lo, raced against threads flooding bare ctnetlink CT_DELETE (flush) requests. Hits WARNING: net/sched/act_ct.c:437 (tcf_ct_flow_table_add(), inlined into tcf_ct_act() in this build) within ~15s on the unpatched kernel; same setup is clean on the patched kernel. The fix itself is behavior-preserving: both branches already did `goto err_alloc` before and after, only the WARN is removed.
CVE-2026-98622
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-2026-98622
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": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "e8fcf3f08834e939b797311742ee72b1e2a08096",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "af475f599270e59313552e6c6f3af8507da672b8",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "424ba52c0058deeb940d02cba52eb0aeb288db33",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "d512c484bd93a5f2794aa03c9faeb7bcb82dbd4a",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "d805560ad69cb266d669341ca01e26bffb0d2c67",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "00734f3684fcec42c319bedfe68a5d357c720b53",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "650787233c2fd6e515a7c5f371019a9fa080ccd2",
"versionType": "git"
},
{
"status": "affected",
"version": "64ff70b80fd403110b67dd9f7184a604fdb0da43",
"lessThan": "47abe7a5c4eb53269aca3506446f851572a059a3",
"versionType": "git"
}
],
"programFiles": [
"net/sched/act_ct.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.7"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.7",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.271",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.222",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.55",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.9",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sched/act_ct.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98622
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38642 · Revision 1
- Added to Heist Feed
- Publisher date