netfilter: nft_set_pipapo: split gc into unlink and reclaim phase
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_pipapo: split gc into unlink and reclaim phase Yiming Qian reports Use-after-free in the pipapo set type: Under a large number of expired elements, commit-time GC can run for a very long time in a non-preemptible context, triggering soft lockup warnings and RCU stall reports (local denial of service). We must split GC in an unlink and a reclaim phase. We cannot queue elements for freeing until pointers have been swapped. Expired elements are still exposed to both the packet path and userspace dumpers via the live copy of the data structure. call_rcu() does not protect us: dump operations or element lookups starting after call_rcu has fired can still observe the free'd element, unless the commit phase has made enough progress to swap the clone and live pointers before any new reader has picked up the old version. This a similar approach as done recently for the rbtree backend in commit 35f83a75529a ("netfilter: nft_set_rbtree: don't gc elements on insert").
CVE-2026-23351
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-2026-23351
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": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "65ca51b9fb85477ab92a04295aed34b38f7c062e",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "c0f1f85097ac2b6e7d750fe4d05807985cd3fd3a",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "16f3595c0441d87dfa005c47d8f95be213afaa9e",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "7864c667aed01a58b87ca518a631322cd0ac34c0",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "c12d570d71920903a1a0468b7d13b085203d0c93",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "500a50a301ce962b019ab95053ac70264fec2c21",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "aff13667708dfa0dce136b8efd81baa9fa6ef261",
"versionType": "git"
},
{
"status": "affected",
"version": "3c4287f62044a90e73a561aa05fc46e62da173da",
"lessThan": "9df95785d3d8302f7c066050117b04cd3c2048c2",
"versionType": "git"
}
],
"programFiles": [
"include/net/netfilter/nf_tables.h",
"net/netfilter/nf_tables_api.c",
"net/netfilter/nft_set_pipapo.c",
"net/netfilter/nft_set_pipapo.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.6"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.6",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.253",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.203",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.167",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.130",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.77",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.17",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.7",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/net/netfilter/nf_tables.h",
"net/netfilter/nf_tables_api.c",
"net/netfilter/nft_set_pipapo.c",
"net/netfilter/nft_set_pipapo.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-23351
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #39839 · Revision 1
- Added to Heist Feed
- Publisher date