net: do not delay dst_entries_add() in dst_release()
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 3.11, 3.13, 3.15, 3.16
- 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: no
- Technical impact: partial
Summary
In the Linux kernel, the following vulnerability has been resolved: net: do not delay dst_entries_add() in dst_release() dst_entries_add() uses per-cpu data that might be freed at netns dismantle from ip6_route_net_exit() calling dst_entries_destroy() Before ip6_route_net_exit() can be called, we release all the dsts associated with this netns, via calls to dst_release(), which waits an rcu grace period before calling dst_destroy() dst_entries_add() use in dst_destroy() is racy, because dst_entries_destroy() could have been called already. Decrementing the number of dsts must happen sooner. Notes: 1) in CONFIG_XFRM case, dst_destroy() can call dst_release_immediate(child), this might also cause UAF if the child does not have DST_NOCOUNT set. IPSEC maintainers might take a look and see how to address this. 2) There is also discussion about removing this count of dst, which might happen in future kernels.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
From 3.10.50 · fixed in 3.11; From 3.12.26 · fixed in 3.13; From 3.14.14 · fixed in 3.15; From 3.15.7 · fixed in 3.16
- Linux Linux
3.16