netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.6.160, 5.16, 6.2, 6.11, 6.12.75, and 2 more
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation Ulrich reports a regression with nfqueue: If an application did not set the 'F_GSO' capability flag and a gso packet with an unconfirmed nf_conn entry is received all packets are now dropped instead of queued, because the check happens after skb_gso_segment(). In that case, we did have exclusive ownership of the skb and its associated conntrack entry. The elevated use count is due to skb_clone happening via skb_gso_segment(). Move the check so that its peformed vs. the aggregated packet. Then, annotate the individual segments except the first one so we can do a 2nd check at reinject time. For the normal case, where userspace does in-order reinjects, this avoids packet drops: first reinjected segment continues traversal and confirms entry, remaining segments observe the confirmed entry. While at it, simplify nf_ct_drop_unconfirmed(): We only care about unconfirmed entries with a refcnt > 1, there is no need to special-case dying entries. This only happens with UDP. With TCP, the only unconfirmed packet will be the TCP SYN, those aren't aggregated by GRO. Next patch adds a udpgro test case to cover this scenario.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
From 74e6eb7fd27ef1ccc68041dbc66e6d80d2e4a1a0 · fixed in aead84bdacd77e08357fd718e5dcaffaf387f3c3; From 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb · fixed in 79b713ef4261a8ead96af4703f89d0b5f25532e2; From 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb · fixed in 23901aa6b8a2f294c4b774436b4691f3ff863a8f; From 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb · fixed in b740e7ddd7ca0dbfeafca3f5e52717206cf28524; From 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb · fixed in 207b3ebacb6113acaaec0d171d5307032c690004; From 6.6.48 · fixed in 6.6.160; From 5.15.166 · fixed in 5.16; From 6.1.107 · fixed in 6.2; From 6.10.7 · fixed in 6.11
- Linux Linux
6.11
- KernelLinux
fixed in 6.6.160; From 6.7.0 · fixed in 6.12.75; From 6.11.0 · fixed in 6.18.14; From 6.13.0 · fixed in 6.19.4