netfilter: ctnetlink: remove refcounting in expectation dumpers
Published Sep 11, 2025
5.5
MEDIUMCVSS 3.1
EPSS 0.17%
Description
Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption.
AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use))
to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.
Affected products
-
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version StatusaffectedConstraints
- Version
-
- Version 2.6.23StatusaffectedConstraints-
- Version 0StatusunaffectedConstraints<2.6.23
- Version 5.10.253StatusunaffectedConstraints<=5.10.*
- Version 5.15.203StatusunaffectedConstraints<=5.15.*
- Version 6.1.167StatusunaffectedConstraints<=6.1.*
- Version 6.12.78StatusunaffectedConstraints<=6.12.*
- Version 6.16.2StatusunaffectedConstraints<=6.16.*
- Version 6.17StatusunaffectedConstraints<=*
- Version 6.6.130StatusunaffectedConstraints<=6.6.*
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
| ||||||||||||||||||||||||||||||
| Linux | Linux | affected |
|
- ≥ 2.6.23 · < 6.16.2
- 6.17
No data.
Red Hat Enterprise Linux 10
kernel
Fix deferred
Red Hat Enterprise Linux 6
kernel
Out of support scope
Red Hat Enterprise Linux 7
kernel
Fix deferred
Red Hat Enterprise Linux 7
kernel-rt
Fix deferred
Red Hat Enterprise Linux 8
kernel
Fix deferred
Red Hat Enterprise Linux 8
kernel-rt
Fix deferred
Red Hat Enterprise Linux 9
kernel
Fix deferred
Red Hat Enterprise Linux 9
kernel-rt
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 6 | kernel | Out of support scope | n/a |
| Red Hat Enterprise Linux 7 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Fix deferred | n/a |
| Red Hat Enterprise Linux 8 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 8 | kernel-rt | Fix deferred | n/a |
| Red Hat Enterprise Linux 9 | kernel | Fix deferred | n/a |
| Red Hat Enterprise Linux 9 | kernel-rt | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
Red Hat mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
References (15)
- https://access.redhat.com/security/cve/CVE-2025-39764 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2394639 Issue Tracking
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2025-28948 Advisory
- https://git.kernel.org/stable/c/078d33c95bf534d37aa04269d1ae6158e20082d5
- https://git.kernel.org/stable/c/1492e3dcb2be3aa46d1963da96aa9593e4e4db5a Patch
- https://git.kernel.org/stable/c/64b7684042246e3238464c66894e30ba30c7e851
- https://git.kernel.org/stable/c/9e5021a906532ca16e2aac69c0607711e1c70b1f
- https://git.kernel.org/stable/c/a4d634ded4d3d400f115d84f654f316f249531c9 Patch
- https://git.kernel.org/stable/c/b05500444b8eb97644efdd180839a04a706be97c
- https://git.kernel.org/stable/c/bada48ad5b0590e318d0f79636ff62a2ef9f4955
- https://lore.kernel.org/linux-cve-announce/2025091147-CVE-2025-39764-b300@gregkh/T
- https://nvd.nist.gov/vuln/detail/CVE-2025-39764
- https://www.cve.org/CVERecord?id=CVE-2025-39764
Change history (0)
No recorded changes yet.