nfsd: validate sockaddr length per family in listener_set
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.12.111, 6.18.50, 7.2.4
- 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
Summary
In the Linux kernel, the following vulnerability has been resolved: nfsd: validate sockaddr length per family in listener_set nfsd_sock_nl_policy declares NFSD_A_SOCK_ADDR as a bare NLA_BINARY attribute with no minimum length. A CAP_NET_ADMIN caller can send a 16-byte NFSD_A_SOCK_ADDR with sa_family=AF_INET6, causing a 12-byte OOB read across three consumers (rpc_cmp_addr_port, svc_find_listener, kernel_bind). nfsd_nl_listener_set_doit() also parsed and validated each listener entry inline in two separate loops, interleaved with mutating the running listener configuration. The validation was duplicated, used an open-coded "nla_len < sizeof(struct sockaddr)" check that was too short for AF_INET6, and handled a malformed entry inconsistently depending on which loop noticed it. Add an nfsd_nl_validate_listeners() helper that walks the entire list once and confirms each entry parses, carries both an address and a transport name, and is long enough for its address family (sizeof(struct sockaddr_in) for AF_INET, sizeof(struct sockaddr_in6) for AF_INET6, -EAFNOSUPPORT otherwise). Call it before taking nfsd_mutex or creating the serv, so a malformed request fails cleanly with no side effects. Since every entry is known valid by the time the two existing loops run, drop the redundant presence and per-family length checks from both, leaving only the nla_parse_nested() call needed to extract the data.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 16a471177496c8e04a9793812c187a2c1a2192fa · fixed in bf85a0f1e45258f90ceeec14772b5769697dfd75; From 16a471177496c8e04a9793812c187a2c1a2192fa · fixed in 2aca70c18c5f5d06004122861fb151d5fcc57faf; From 16a471177496c8e04a9793812c187a2c1a2192fa · fixed in 22d0e4752ca88fd84196d22ebeedc905e6540440; From 16a471177496c8e04a9793812c187a2c1a2192fa · fixed in bdcc85c2b05a9378d8bd2d65f9fc41440a3cf464
- Linux Linux
6.10
- KernelLinux
From 6.10.0 · fixed in 6.12.111; From 6.13.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4